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Outdoor Free Flight Forum => Tip Launched Gliders => Topic started by: BG on December 27, 2009, 08:25:59 PM



Title: Sweepette 36D -Build-
Post by: BG on December 27, 2009, 08:25:59 PM
Ok folks... I have decided to do a SWE 36D.

1st... I have a nice piece of 48 inch 3/8ths c-grain that comes in at ~7 lb/sq inch. The piece is straight and stiff with a density gradient across the sheet from ~6lb to 7lb+. My plan is to use this piece for the 36D wing with the hard side at the TE.

2nd. I am wondering what the 36D components should weigh in at? Lee if you have a mo. could you post the weights for your recent version?

3rd. Are there mods I should make to the plan to get a SWE36 the flips nicely in the transition (as per your "went flying" description).

thanks in advance for your advice and suggestions.

Bernard



Title: Re: Sweepette 36D -Build-
Post by: Pit on December 28, 2009, 07:04:15 AM
This build will be interesting! Some of the guys in my club are playing with the smaller rc TLG's of ~1 meter span and have mentioned the FF activities - which really surprised me. One was very unhappy with the way the stock wing was (NOT) performing and said that he might order a wing blank from the States. I'll steer him to HPA.

Be sure to post LOTS of pics, cause I'm also toying with going "giant scale" ;D.

Pete

PS: have you done any more testing with your "Scalded-cat"? PB


Title: Re: Sweepette 36D -Build-
Post by: BG on December 28, 2009, 11:50:56 PM
Ok Here we go:

Last night I started the process by selecting wood for the tail feather (stiff ~5lb c grain) and the fuselage (stiff 8 lb A grain 1/4). Also cut out some 1/32nd ply cheeks for the fuzz (photo 1). I cut the ply with the shears in the photo or with regular household scissors.

Next I prepped the fuselage for a built in viscous timer:
1. I adhere one ply fuzz cheek to the balsa core (pick the side you want your DT tube to stick out of).
2. Drill a hole through the fuzz that is the same diameter as your DT tube (mine is 1/8th aluminium).
3. drill as second hole up to but not through the ply that is the same diameter as the next size up of tubing (5/32nds in my case).
4. Counter sink a 8 mm diameter hole about 3 mm into the balsa core centered on the previous hole. This will be your silly putty reservoir.
5. Cut of a piece of the outer 5/32 tubing that is about 2.5 mm long and insert it into the hole so that it is flush with the inside surface of the ply cheek. CA in place and CA all round the reservoir to stiffen and seal.
6. Cut you DT tube so that it projects ~ 1 cm out of the fuzz side while flush against the inside surface of the opposite play cheek (~17 mm).
7. Drill a 1.5 mm hole through the tube about 1 mm from one end and inset a 1.5 mm, ~ 6mm long rod (I used carbon) through the hole, center it and CA in place.
8. Drill a second hole through the tube about 4 mm from the other end...this hole will take your timer arm.
9. Cut a 2nd piece of 5/32nd that is ~1 mm long and slide this over the timer tube so that when the timer tube is inserted this collar will keep the short "paddle rod" from binding against the base of the reservoir.
10. insert timer tube and check that she rotate freely and does not stick out beyond the side of the balsa core.
11. pack your reservoir full of silly putty.
12. Adhere second 1/32nd fuselage cheek... this seals the DT mechanism in place.
See photos 2-5

I also prepped my wing blank for by gluing a ~1 inch wide strip of 8lb 1/8th to the TE because the wing has a 5 inch chord and I had a standard 4 inch wide sheet of C grain for the main portion of the wing.

The last photo shows all of the bits ready for the next step... rough shaping.

Bernard


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on December 29, 2009, 01:42:06 AM
Hi Bernard,

Glad you have got going on your SW36D build so quickly. Let me see, where can I help you?

Firstly, the wing chord is only 4.5 or maybe 4.57" if you put a 2mm or .062" basswood strip on LE as I recommend. I think 7# stock will be a wise choice. Good strength & torsional rigidity. BTW, my two have .015 & .025" undercamber respectively, from about the max thkns curve rearward, going to zero at 16" from root. I tape off the d'dral joint lines before sanding u/c, then cut & add d'dral. See photo attached.

The outer joints have the u/c blended after joining. The center joint stays unblended til sanded flat for mounting.

Do the entire top and the LE shaping with upsweep [aka Phillips entry] before sanding u/c. Or... don't add the u/c. It IS a lot of work, but I think it really helps the glide, with little or no lost climb.

Now for my spec weights as you asked for:
Wings RTM [ready to mount] = 37.5gms for -1 & 39gms for -2.
Stab RTM = 1.7 - 1.9gm Fin = .5 - .8gm of strong balsa with .03 bass strip protection.
All 4 of the 36" TLGs I have made had ~.290" thk wings & weighed between 78 and 85gms, RTF.

We await your next posting. 8)

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on December 29, 2009, 03:11:26 AM
Good stuff.

Leeper, I think that Bernard was interested in the changes done to "Jugs2" compared to plan. I believe that you stretched the TMA n'est pas? And the dihedral is a bit more than plan is it not? New CG would certainly be of use.

Tmat
-lurking in the shadows... ;D


Title: Re: Sweepette 36D -Build-
Post by: BG on December 29, 2009, 08:46:15 AM
Hi Guys,

Thanks for the info Lee.

Some questions for clarity:
1. The undercamber is 0.6 mm (.025"*25.4.....sorry I prefer metric ::)) ??
2. How far back from max thks do you hit max undercamber? See my foil guestimates.
3. FOr the center joint....so you don't blend? You just sand a flat bevel that is perpendicular to the vertical joint plane so that you have a flat spot to mate to the fuzz?

Lastly, as Tony notes, I would also be interested in the TMA and dihedral values for JugsII as well as the CG of course.

thanks
B

Another general question: Why not taper the blank from the root to the tip with a constant taper? This would give you a lighter (but thinner) wing. Is it because of the loss of strength? Or is it because of the loss of lift from a thicker foil? or both? I ask because my blank is 10 mm thick and I was thinking about tapering from 10 mm at the root to 3 mm at the tip for a constant taper. Is this a bad idea in general? if so why?

Note: I will stick to the config. of jugz II but I was wondering if the alternative config. above would be ok?


Title: Re: Sweepette 36D -Build-
Post by: Olbill on December 29, 2009, 11:35:17 AM
Bernard

The timer is slick! Have you used this design before? Is it pretty consistent?


Title: Re: Sweepette 36D -Build-
Post by: BG on December 29, 2009, 12:47:08 PM
Thanks Bill,

Nope, have not tried it yet but I am confident that it will work ok.

B


Title: Re: Sweepette 36D -Build-
Post by: climber on December 29, 2009, 01:08:10 PM
This looks neat. I just downloaded the plans and I may have to try one.

How is the incidence adjusted?

Craig


Title: Re: Sweepette 36D -Build-
Post by: Tmat on December 29, 2009, 01:26:46 PM
With a screw under the tailboom in the pod.

Tmat


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on December 29, 2009, 01:36:42 PM
Bernie,

FYI, the SW36D plan I sent you has the correct 17" TMA & d'dral for Jugs-2.
Jugs -1 has slightly shorter TMA [16.2"=411mm] & 2.25" CG.
Jugs -2 has CG back slightly @ 60mm[2.36"] due to longer TMA.
I did not chg CG on plan so the builder can start on the safe side, then fine trim CG to suit.

Q2: The u/c max of .6mm is about halfway from max thkns to TE.
So I would say back a bit from 27mm value on your foil estimate. After I removed the green tape used for u/c sanding [See my pix of u/c sanding tapeoff], I blend-sanded in front of where tape was, as there was the slightest ridge at tape edge, of course.

Re Q3: why blend u/c at CL, when you must prep that area flat[as you succinctly state [perp to joint] to mount to body? That is SOP with most HLG flyers these days. It is a useless waste of effort to try to cut & fit groove in body for wing. Flat to flat is best.

Re "Another general question": for SW shaped wings and most other shapes, I feel it is best NOT to sand taper straight from CL to tip. Especially on TLGs. As you stated, strength is needed for tip launches. By definition, an elliptical [or nearly so] LE planform will result in a near elliptically curved HP after shaping airfoil. I determine my thkns goal for center, then calculate thkns for d'dral joints as ratio. I like to think overall lift is better in doing so, but that is an unknown.

FYI: my thkns: root=.29"; at d'dral joint=.265"; & .23" @ 13" from root.

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: climber on December 29, 2009, 01:42:41 PM
Ah, ok.

So the screw head is accessed through a hole in the boom or do you have to have it in D/T mode to adjust it? Does the boom rest against the head of the screw and loosening it raises the tail up a little?

Craig


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on December 29, 2009, 02:18:05 PM
Craig,

Tony should have said the screw is ABOVE the boom. It is mounted in the body recess between the plywood sideplates. Adjustments made in DT position. Boom is pressing on screw head in flight mode. Can't attach pdf file to show this in planform.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on December 29, 2009, 03:40:42 PM
I always think of it as being below the boom because in my muddled thinking, the plane is always upside down when I make the adjustment. But in the true sense, yes Leeper is correct, the screw is "above" the boom. To answer Craig's question, the boom must be in DT position to adjust the declage and yes the boom rests against the screw head.

You can see the screw in the photo I've attached (it's an underside view showing the plywood side cheeks creating a guide for the boom). You could probably come up with a way to adjust the screw without moving the boom out of the way, but in practice I find I am usually adjusting the declage right after a test flight that has DT'd (short DT's for test flights) and so the boom is already out of the way when I pick the model up. I keep a precision screwdriver in my pocket at all times when flying so that adjustments can be easily made "on the fly" as it were.

tony


Title: Re: Sweepette 36D -Build-
Post by: climber on December 29, 2009, 03:48:48 PM
Again: Ah.

What are the notches on either side of the fuselage right where the screw is? Are those to keep the D/T bands in place?

Craig


Title: Re: Sweepette 36D -Build-
Post by: BG on December 29, 2009, 04:04:48 PM
Hi Craig,

Yes the notches form a slot so that the DT band can press directly on the boom ensuring firm contact with the adjustment screw (any slop would be bad of course).

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on December 29, 2009, 04:39:52 PM
Actually Bernard, we usually run the DT line (Nylon, or Spiderline type of material) around the bottom of the boom to provide the boom hold-down force. The only rubber band used is to pull the boom up into DT position. Here is a link to my web album showing some of Stan's DT system in detail with some photos and a short video. http://picasaweb.google.ca/tmathews180/PopUpBoomDTDetails#

You will see that the notches are to allow unfettered contact with the boom. I've attached Jim Buxton's excellent exploded view of Stan's TLG DT system as it describes the set-up better than I ever could. The only change that I make over Stan's system is that I attach the fixed end of my DT line to a pin (or a small wire loop) rather than glue it into the wing. This way I can replace the DT line if need be (not that I have had to yet mind you).

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on December 29, 2009, 05:31:24 PM
Bernie,

I must disagree with Tony here re DT line material to use. [Note: Jim Bux does not mention line of choice in his exploded view.] I [and Stan B's customers, etc] use Dacron line of about 20# test or lower if can be found. Because it is limp. No Nylon nor Spiderwire I have ever seen is limp enuf for the job. There might be some out there, but please try to find 'flyback line' in the test poundage noted above. Micron by Courtland was the best dacron line I ever used, but it may be obsolete.

As for anchoring DT line, I drill 1/16th hole thru wing on right side of body, insert 1/16th alum tube, then pass line thru and tie off when calibrating proper tension. Put dab of CA on knot AFTER you pull it out of tube! This method allows easy tension increase adjustment, which is the normal thing that occurs. Certainly it give ease of replacing lines.

Plus it suits my style & gives me peace of mind! ;D ::)

Ciao,
Leeper

PS: And if it is not too late with your wing layout, whenever possible try to make the inside [read 'glideside'] wingtip the heavier side. But ONLY if the grain choice will still be optimised by so doing. :)


Title: Re: Sweepette 36D -Build-
Post by: Tmat on December 29, 2009, 07:02:53 PM
I've used Dacron as well, but now prefer the low-stretch Spectra as it does not give and allow the boom to shift. So I don't need to worry about a mousetrap arrangement. It is flexible enough to wrap around the boom and slippery enough to slip between the turnaround for easy release. But to each his own of course.

Tmat


Title: Re: Sweepette 36D -Build-
Post by: Pit on December 29, 2009, 07:05:44 PM
Other than the known abrasiveness of Kevlar thread, would it work?


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on December 29, 2009, 07:30:18 PM
Re Spectra, I have avoided it as I felt it might be TOO slippery at turnabouts to withstand aero forces.

Kevlar might work, but it is fuzzy and might snag on something. Beware Murphy's law. Why not just use some good sewing thread of proper size? Much of it is Dacron or similar [linen?] Easy & cheap to buy.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on December 29, 2009, 07:52:53 PM
The spectra based fishing line I've used is not as slippery as the pure Spectra so it works just fine.

The only area that I'd like to use a different line (or diameter) is the piece that runs from the coil spring to the timer. My Power-Pro braided line (30 lb test) http://powerpro.com/publish/content/global_fish/en/nl/powerpro/products/powerpro_family_of/powerpro_super_lines.html is a bit thin for finger handling at the timer end. Other than that, it works really well for me. I'm sure there are other similar Superline products that will work just as well (Spectra based).

Any decent strong thread will work and I don't think it's critical what you use.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on December 31, 2009, 05:51:59 PM
Hi All,

Interesting thread ( ::)) ....so here are some more pictures of progress. I spent a few hours making some tools to help me with the wing sanding process: Undercamber sanding block, top front camber block, upsweep block, squaring sander (just a piece of flat 1/4 with another piece with sandpaper mounted on it at 90 deg. so that I can square off the edges of the wing before attaching the basswood), and a marker made of 1/32nd ply that allows me to mark a groove to guide me as I attach the basswood.

Also added the basswood LE and started to plain wood off the wing.... this is some beautiful wood by the way.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on December 31, 2009, 06:07:30 PM
Yes B, it surely is beaut wood. Makes it more than pleasurable to be privileged to shape, does it not? :)

A good idea you had, re LE squaring up before attaching basswood. You are going to ease up on the upsweep & u/camber as you near tips, aren't you?

Looking very good... wish I was there hacking something out with you!

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 10, 2010, 03:28:59 PM
Hi All,
No photos (wife has the camera) but I did finish the tail feathers last night. 1st outlines the stab with thread and CA then sanded to foil using the methods outlined by Tmat in several posts on cat gliders (see here: http://picasaweb.google.ca/tmathews180/LongcatBuild#).

The weights for the fine sanded fin and stab are .5 and 1.5 g respectively. The fin has top camber sanded in on the right side (I am a lefty).

Bernard


Title: Re: Sweepette 36D -Build-
Post by: BG on January 13, 2010, 11:23:35 PM
Ok Wife is back and here is the next installment of build shots.

1. Wing prepped for sanding on new plate glass. I used small squares of double sided tape that I have detacked with a cloth (so that I can get the wing off the glass later) to hold the wing in place during sanding/shaping.
2. Sanding the back of the foil top. The space between the wing TE and glass edge determines the TE thickness. The tap at the high point prevents oversanding the high point. This method allows you to sand a nice flat rear foil.
3. Rough sanding the LE curve. Here I am using a tool to get the correct shape on the top camber.
4. Thread glued to the TE ... I make a shallow groove first and then CA the thread in place. Here you see it after sanding. I do this to keep the TE nice and clean and to strengthen it.
5. Wingtip after fine sanding
6. Wing after the top foil has been sanded in. I finish the surface with fine sandpaper held in my hand.

Tail feathers next.


Title: Re: Sweepette 36D -Build-
Post by: BG on January 13, 2010, 11:26:42 PM
Here are a couple of shots of the Fin and stab:

1. Stab. The stab is lines with thread and has been fine sanded. THe weigh is 1.5g
2. Fin with foiled right side to generate a left turn.

Ok that is all for now.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 13, 2010, 11:51:34 PM
Looking good Bernard!

Man, that is some nice balsa in that wing! Nice to see you've done it justice with the fine shaping job.

Did you sand the undercamber before shaping the top, or will you do it now?

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on January 14, 2010, 12:35:17 AM
Thansk Tony... yeah she is a lovely piece of wood... light stiff and very pretty. Tis an honor to work with her.... now if I could just find all of the other bits from that tree :P

Under camber is next. I have done the flat tip undersides with zero upsweep as per the Leepers instructions.
B


Title: Re: Sweepette 36D -Build-
Post by: BG on January 19, 2010, 12:00:40 AM
Ok. Here goes with the next series of SWE36D build photos:

1. Shaping the upper front camber with a shaped sanding tool. I use tape to protect the high point and do the initial work with the razor plane.
2. Shaping the lower front camber (upsweep). Note the stops glued to the sides of the tool.... these do not have sand paper and prevent over sanding.
3. Shaping the under camber.... this tool also has stops etc. I found this to be time consuming.... I put in about 0.8 mm of under camber. Leeper uses 0.6 (see earlier post for details.
4. Last detail before minwax.... there is a ~ 1 mm flat spot on the bass.... I am not sure why this remained as the sanding tools should have resulted in a sharper LE....
Do I:
a. Sand in a Stan B. flat to cut the LE down to a sharp entry.
b. sand the upper and lower LE by eye to get a nice rounded knife edge.
c. Sand in a bit more upsweep.
d. Sand in more down-sweep.

Your thoughts appreciated as always.
Bernard
P.S. Wing now weighs in at ~37 grams.


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 19, 2010, 12:29:07 AM
Good job Bernard. Typically, after I have finished with the curved sanding tools, I also have a leading edge that is not rounded the way I'd like it to be. I sand it by hand to the required radius. Try to make the leading edge a nice smooth, rounded, yet sharpish (if you know what I mean?) entry that blends with the top and bottom curves.

Leeper didn't use the Stanfoil flat on his Jugs, so I'd lean towards not adding one also.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on January 19, 2010, 01:11:50 PM
Thanks Tony... that is what I thought too... So the LE has been finished as suggested and the first coat of minwax is drying. Coat #2 tomorrow after fine sanding.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 19, 2010, 05:20:29 PM
What Paul Love and I have been doing (and now even Leeper too!) is to scan the actual airfoils after cutting the wing blank apart at the dihedral break. I place the wing vertically on the scanner and hold it steady. Paul uses Lego blocks and some such jigging to get his pics. I've attached a sample of one of my airfoil scans from my Longcat build. This allows you to record what you actually made, and it is possible trace the airfoil using Profili and analyse the performance in X-foil (if you are into that sort of detail that is ;)).
I don't finish my wings until after I join the dihedral breaks and so does Leeper. Other people finish the wing before cutting apart the d-breaks. You could (if so desired) after looking at the airfoil scans, tack the wing back together and re-sand if you thought you had goofed up the airfoil. So far (touch wood) I haven't had to do that. This is far easier to do if the wing hasn't been finished.

Leeper could attach his SW36 MKII airfoil scans for you to compare with yours. Leeper?

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on January 19, 2010, 05:50:08 PM
Hmm that is a good idea....I will make the cuts do the scan for a check, then tack the bits back together for finishing while flat (or reshaping etc). When the second to last coat of minwax is on I will rebreak the joints and sand them for joining etc. then I will add the ply d'hedral braces and glass the wing joints. Last thing will be a coat of tinted minwax. I am gonna use thinners with pieces of sharpie wick dropped in to tint my minwax deep blue for the undersurfaces). For the top I will use the same procedure but with florescent sharpie wicks. The undersides of the tips will have a florescent orange or pink slash.

Glassing wing joints: This is a problem area for me I have to admit.....how do you guys do it so that you get a nice smooth finish with a seamless transition from the glassed area to the unglassed wood? What do you use to adhere the glass? Duco? Dope? MinWax? Epoxy? Is it thinned or straight? Do you tack the glass to the wood with spray mount first? I would hate to ruin this wing with a poor glassing job.

thanks in advance.
Bernard


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 19, 2010, 06:53:00 PM
Hi All,

Back from Eloy and had a great time. My newest Sweepette 36D [aka Jugs 2] is really flying well and took the win at SWR 2010.

Bernie: very good to see your fine progress! Yet I wonder why you apply finish before gluing the bits to the body? I fear less than ideal adhesion under stress.

Tony: I did not scan Jugs 2 airfoil. The critical dims are near identical to Jugs I: .295 thk @ 1.25hp, .06 upsweep blending ~ 1" from LE & .025 u/c going to zero near tips. But you both already know that, eh?

Re glassing the critical areas: It is easy. Put Duco Cement drops where you will lay the fiberglass & spread out some
with finger. Quickly position piece on glue spots & flood with MEK [dope thinner might do] then use dowel or equiv to squeegee the glue evenly thru the cloth. Blot the wetness with blue paper towel pieces. Allow some drying time. Glassing is best done after dihedral joinings and wing attached to body. Sand glass lightly. Then apply finish of choice, IMO.

Attached are current pix of Jugs 2. One shows bottom colors. The Maroonish Red is a Design Masters color called Cranberry. It seems to show up well per my timekeeper.

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: Olbill on January 19, 2010, 09:21:29 PM
That's a gorgeous model!


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 19, 2010, 09:27:23 PM
Gee, thanks Bill... :-[ :-[ :D

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 19, 2010, 11:05:38 PM
I'll second that... this is a nice looking model you have produce Lee.

On my version.... point taken it does not make much sense to apply the finish under the areas where the glass patches will go or where the wing mates to the body. These areas will get a roughing prior to glass application to ensure proper adhesion.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 19, 2010, 11:12:24 PM
I'm with Leeper on this one. Why finish the wing before glassing at all??

I do prefer to finish the wing before gluing it to the fuselage though. I mask the area off at the joint so that no finish is applied to the glue joint area. I find it easier to handle just the wing when finishing and sanding. But I'd rather have the glass bond to the bare balsa.

But Buxton and others finish their wings before doing the dihedral joints so you are not alone Bernard.

Leeper, remember the photo below?
You said it was a scan of SW36RDT from Dec 01st aprox. If not from JugsII, then what? Memory going again?? ;D ;)

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 19, 2010, 11:39:06 PM
OOPS! Yep, real gone. :-[

But Tony, that was way back 50 days ago. How am I supposed to recall that? ::) But you see, remembering this stuff is what I trust you will do to assist me! ;D Will you be my caregiver in my [future] dotage? ;)

Back on subject: Bernie, it seems you have everything under control and the build will turn out fine. Oh yes, your wing weight is nearly same at my two: 37-38gr RTM, as I expected when viewing your fine wood. 8)

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 19, 2010, 11:41:50 PM
Will you be my caregiver in my [future] dotage? ;)

Whada ya mean future??? :D :o ;) ::)

Tmat
-couldn't resist...


Title: Re: Sweepette 36D -Build-
Post by: malc on January 20, 2010, 09:20:07 AM
Several of you refer to Minwax for finishing bare balsa wings, which Minwax product do you use, is it the water based oil modified polyurethane or water based wipe on poly? Or something else?

Malc.


Title: Re: Sweepette 36D -Build-
Post by: Randy Reynolds on January 20, 2010, 11:00:11 AM
Malc, I believe most of us us the MinWax Spar Urethane which can be found at Home Depot, Ace Hardware and Michaels. I don't think it is waterbased. The Spar Urethane is intended for outdoor use and has a UV inhibitor which is helpful to avoid warps in the sun. I know some use thinned Nitrate (non-tautening) over powdered bat's wing applied with chicken bones but you should avoid those people.


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 20, 2010, 11:55:22 AM
Hah! RR, I don't recall telling you of the batwing powder finish, but luckily you left out the most critical ingredients: Eye of newt & ... something else... oh yes, tongue of frog! :-X :D

Serious now: the Minwax most try to find is petrol-based. I & some other folk use good mineral spirits if you want to thin it. I usually go about 20% thinner. Dries in about 6-10 hrs. Try to cure it in warm place, like sunny patio, etc. You can brush or swab it on, then evenly spread-wipe with blue paper towel squares.

I haven't had to resort to the powdered batwing stuff since we found Minwax. :D

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 20, 2010, 12:24:23 PM
Malc,

When I was living in Germany I searched Obi, Bauhause, the other big hardware store for Minwax... they don't have it. I did find a urethane varnish that boaters use to varnish wood on yachts etc. This stuff has a UV inhibitor and is water proof etc. I think it will do the same job. Just ask for a yacht varnish with UV protection.

B


Title: Re: Sweepette 36D -Build-
Post by: BG on January 20, 2010, 06:12:03 PM
Lee and all,
Any chance that I could use acetone instead of Mek (I don't know what this is or where to buy it). I thin Duco with acetone for building etc. I hope to cut my wing tonight... just to confirm... I do cut wedges out of the outer poly jnts to get washout per plan correct?

thanks
B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 20, 2010, 07:01:02 PM
Bernie,

Just cut the joint on the line which the plan describes, sand and glue d'dral joints. No wedge cuts required. They would add sweepback, which is not needed really. The towout line should measure .13" from perpendicular, but even .19" is fine. You will notice as you raise the tip how the TE comes up slightly higher than the LE. Hence, automatic washout. [Tho I do always sand in just a bit in the last part of each tip.]

Acetone is OK to flood the Duco with. Not much different from MEK as I understand things, chemistry-wise. MEK is Methyl-Ethyl-Ketone. I seem to recall acetone is one level down the ketonic scale. Chemical engrs, please jump in here, if I am off-base. I can get both MEK & Acetone at nearby boat-maker suppliers, btw.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Randy Reynolds on January 20, 2010, 08:16:43 PM
One thing to do after cutting the wing and sanding the dihedral angles is to to "proof" the cuts by placing the panels back to back and using straight angles with a small trisquare to make sure everything is accurate. Sanding in these angles is a lot tricky than you might think and I can testify that this is the step that can turn a excellent flyer into a nightmare.


Title: Re: Sweepette 36D -Build-
Post by: BG on January 21, 2010, 02:39:01 PM
Ok folks the wing has been cut... here is a scan of the root and dihedral break foils... NOTE: this image does not accurately represent the foil as the undercamber still needs to be added at the root cut line and will only be completed after she is glued up etc. Also... I used a rubber band to hold the panels to the red block and this caused the panels to flex flat against the block removing the undercamber and cause the reflex along the rear portion of the foil.

Anyway it is what it is.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 21, 2010, 02:59:08 PM
Bernie,

A key suggestion at this time:

Undercamber sanded at center [root] chord is unnecessary & waste of effort.
Just prior to gluing wing to body, sand the center joint flat for ease of mounting. Use rough sandpaper block, or jig it above a sandpaper covered flat surface, then sand bottom such that the upsweep is about half gone.
It takes but a minute to do.

That is our standard operating procedure re wing mounting prep.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 21, 2010, 03:04:12 PM
HI All,

Yeah sorry... I should have said "poly jnt cut line" .... I had no plans for sanding in the UC at the root. Was planning a horizontal bevel as you suggest.

B


Title: Re: Sweepette 36D -Build-
Post by: BG on January 21, 2010, 03:57:23 PM
Lee says (with minor edits for clarification by me):
The rear center joint is just kissed when sanding the horizontal bevel for the wing-fuselage joint.
The intent is to lower LE slightly.
Plus, It will help the CA adhere the joint too.
 
I put some pinholes in each side of wing cuts before gluing d'dral joints.
Do same for body & wing at interface before attachment.
 
FYI, after all surfaces joined to body, I run a bead of medium CA along interface then blow some microballoons on and quickly blow off excess.
This forms very strong and usually smooth fillets.
Do same for fin & stab.
 
Leeper
 
I reply: Thanks for the sanding tip, and yes pinholes and microballons were in the plan.
Lastly... check out the planned color scheme...the orange on the lower surfaces will be fluorescent orange.

Bernard


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 21, 2010, 05:10:26 PM
Bernard,

I think that you did an excellent job with your airfoils! Well done. Your model should fly very well.

Leeper's SW36D is one of the best flying TLG's and if you ask me (for what it's worth) the best gliding model out there. She really floats and just looks "happy" in the air. ;D

Good luck!
Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 21, 2010, 07:34:35 PM
Thanks Tony, for the kudos. :-[

Bernie, that is a HOT color scheme! :o :-*

I just wish I had the opportunity to see it fly!

I do feel an attachment to it, strangely enuf...don't quite know why... ;)

Very nice job you are doing. ;8)

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 21, 2010, 09:56:12 PM
Lastly... check out the planned color scheme...the orange on the lower surfaces will be fluorescent orange.
Bernard

Bernard, I like the color scheme. May I suggest fluorescent orange on the top surface also? I have found that having the bright flo orange on the top of the tips as well as the bottom really helps to find the plane in the grass in Canada.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on January 22, 2010, 12:41:32 PM
Hi All,

Here are a series of shots of the wing assembly:

1. ready for joint bevels with sanding angle jigs at the ready.
2. Sanding in the joint bevel (for dihedral).
3. Prepped joint surface... ready for glue. I do this on both joint surfaces
4. Joint with glue... most of this is soaked up by the perforations I made in the joint.
5. The joint... nice and tight
6. Completed wing with flat beveled at the center.... as she sits there is 1/2 mm height difference from left to right.... the bevel was eyeballed (I am always amazed at how the human hand and eye can get things so close to square without jigs etc.).

Next dihedral braces and then glassing.

Bernard


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 22, 2010, 01:10:28 PM
More fine work from BG! It will fly like a dream, I wager.

Re shot 6 and your comment: Amazement shared by me for many years as well. :o

Hands & eyes are super-coordinated tools, yes? ;D

Two queries: 1. what glue did you use as shown in shot 4? 2. how much did wing weigh RTM?

Still tuned in to this channel...

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 22, 2010, 02:18:29 PM
Hi All,

Lee, the glue is thick CA. I like this because it has a second to infiltrate my perforations before setting up. Thin CA might set too fast. The wing feels very strong.

The weight is 38.5 grams. I guess I will be up over 40 after braces, glass, and final finish are applied :-[.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 22, 2010, 03:51:08 PM
Bernie,

That is right at normal RTM wing weight. The final additions you mentioned are likely to be virtually same for any TLG. And my bet is you will find weight needs to be added to glide-side tip for turn adjustment.

Again, SOP for TLGs, eh?

Carry on...
Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 22, 2010, 04:54:22 PM
Thanks for that info Lee... I was quite bummed out for a mo there.

So do you have an idea as to your wing weight after glassing and braces plus finish or is this all applied after mounting to the fuzz?

Also, how much weight do you typically end up adding to the inside tip?

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 22, 2010, 06:02:28 PM
Bernie,

Go back to my first page reply: post #3 in this topic. Much of my notes info is there to answer you.

My RTM weight values are before glassing or any finish, but after cutting slots & adding the carbon gussets to throw-side d'dral joint. So your's is quite close to mine. Makes sense. Wood was near same density, so volume is nearly equal.

Start with enuf weight so the inside tip is slightly lower when balanced on fingers upside down. Finer setting will be made as trimming progresses & you get to know the bird better. I & some of the others even find they need OUTER tip to be the heavier...not always, tho.

I also router [after glassing] a pocket on wing center top for recessing the hook for popup rubberband. Pic attached. Scale shows it at 2" from TE. I used thin CA & some Mu balloons to finish it off after I took pic.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 22, 2010, 06:05:01 PM
Here is another pic showing after CA and Mu balls added to secure hook.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 22, 2010, 06:30:19 PM
Thanks Lee... I assumed that you RTM was for a fully finished wing etc. Now things make more sense. I am right on target as you note. Also the pic of you center joint is helpful... I can see what the glass job should look like etc.

More progress as soon as I have time....got a lot of work to do this weekend.
B


Title: Re: Sweepette 36D -Build-
Post by: BG on January 26, 2010, 06:38:50 PM
Hi All, here is the next installment.

1. Photo of the glassed wing tip.... I used the method described by Leeper above (duco and acetone) and it seemed to work very well.
2. Poly joint with carbon brace (I have some photos of the brace installation procedure etc. forgot to download em.... tomorrow!)
3. Center joint glass job.
4. Whole wing ready for paint weight 42.5 grams
5. Wing with black under surface... black paint added 1 gram. I expect the rest of the finish to add less than this.

Weights at this point:
Fuselage pod - 10g
Wing - 43.5g
Stab - 1.8g with final finish including black paint.
Fin - .5g

I am assuming that my boom will weigh in at ~10g and I will need 20g of nose weight. This puts me at ~ 80g for AUW which is on target more or less.

Bernard


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 26, 2010, 07:42:27 PM
Sure looks the part, Bernie!

Curious as to what brand of black paint you used? If it's Design Masters, you seem to have a very opaque coverage, which might be reason it added one gram. I generally don't try for that much blackness, just spraying on a bit more that a fully misted color-coat. If it is Design Masters or an equiv spray paint with acetone or other high-volatility thinner as carrier, it will keep getting lighter in days to come. But you probably knew that... :-\

We have found a gusset on glide-side joint is not needed, but does not hurt anything, of course. The launch-side joint seems to take most of the strain. That is why I use two gussets there on my 36" TLGs.

You are almost ready for liftoff!

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 26, 2010, 08:49:23 PM
Hi all,
Lee it is design master and yes it is opaque. It might not be exactly one gram as the scale I used is not too precise. Could be .5 grams (?). Also that was soon after spraying so some propellent has evaporated since and the weight of the finish will drop. Does not matter much anyway eh?

B


Title: Re: Sweepette 36D -Build-
Post by: Kit on January 26, 2010, 09:01:04 PM
Lee,

Is the recess for the rubber hook just cosmetic or does it serve some other purpose? And how did you put that little knob on the end of the hook? Slick.

Kit


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 26, 2010, 09:36:39 PM
Bernie, in that case, I reckon it will be closer to .5gr after dryout. As you said, mox nix.

Kit, you need to buy a Stan Kit! [shameless plug for him... ;D] He supplies bent pins to suit various hook tasks as needed for the design. I think you will recall from past posts that most of my recent fleet of gliders have been at least started from his kits, even if I use my own planforms. So the function of recessed hooks is to keep the DT line from snagging at release, which can mean boom may not elevate enuf to bring glider out of thermal... bye bye! I had it happen, but got the glider back after a bit of a chasedown. ::)

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 26, 2010, 09:54:57 PM
Looks good Bernard!

So, how did you mask off the black to produce the nice crisp rounded areas for the Orange?

Tony
-enquiring minds might want to copy it you know ;)


Title: Re: Sweepette 36D -Build-
Post by: Olbill on January 27, 2010, 12:00:34 AM
I've also adopted the glass application method Lee described. It works like a charm. This after spending a lot of time previously with carrier sheets, 3M spray, etc. For my light gliders I rub some thinnned Duco into the wood, let it dry, put the piece of glass where I want it and then put a drop or two of acetone on top of the glass. It works like magic to stick the glass down without moving it or distorting it.


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 27, 2010, 02:21:21 AM
I truly like that idea, Bill and will use it for sure!

With a coat or three of Minwax Helmsman Polyurethane brushed or swabbed over your Duco/acetoned glass application, it would be good to go for outdoor use! :) The urethane really assists adhesion of various composites: f-glass, kevlar and carbon, in my experience.

Thanks for the tip.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 27, 2010, 07:49:36 AM
Tony,

I make the pattern with ordinary paper and in this case use glue stick to adhere it to the wing surface. Then spray lots of light coats. After you are done just wet the paper pattern and it comes right off. A wet rage allows you to clean any residual glue from the wing surface. That is it.

BTW.... devolatization of the paint during the day cut a few tenths of a gram off of the paint job.

Next the red and my decals.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 27, 2010, 10:56:00 AM
Clever, paper and glue stik. I can do that (I think ;D).

Did you cut the paper with scissors or a sharp knife blade?

Can't wait to see what she looks like altogether Bernard.

Tmat


Title: Re: Sweepette 36D -Build-
Post by: BG on January 27, 2010, 11:44:40 AM
For cutting masks I usually use a sharp knife (I can cut a smoother line by hand than with scissors).

Also, the photo does not show it but I did get some little run-unders along the mask edge.... I will clean these off with a knife blade. I think this happens where the glue was too thin or where the propellant dissolved through the glue. Anyway I think the solution is more thin coats of pain (I was in a bit of a rush to get it done before running off to school).

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 27, 2010, 12:05:07 PM
I've made some masks myself in the past using Post-it notes cut up into pieces suitable for the job at hand. Produces a nice mess free mask that is easy to remove and doesn't require any clean up. However, it would be tough to use for the fully curves outlines that you produced.

Designmaster Floral spray is prone to creep under masks I've found. The carrier solvent is very thin and it can run along the little grooves in wood grain under tape. You are right, the only solution that I've found is to use several fog coats at the mask line until the paint has sealed the joint. Then you can paint over it with a heavier coat.

Tony


Title: Re: Sweepette 36D -Build-
Post by: ram on January 27, 2010, 12:31:40 PM
I've made some masks myself in the past using Post-it notes cut up into pieces suitable for the job at hand. Produces a nice mess free mask that is easy to remove and doesn't require any clean up. However, it would be tough to use for the fully curves outlines that you produced.

Designmaster Floral spray is prone to creep under masks I've found. The carrier solvent is very thin and it can run along the little grooves in wood grain under tape. You are right, the only solution that I've found is to use several fog coats at the mask line until the paint has sealed the joint. Then you can paint over it with a heavier coat.

Tony

The traditional way would be to spray the lighter color, then mask it off. Spray another coat of the lighter color over the mask edge. It will bleed along the grain and seal the edge, but the bleed under is the same lighter color. Then spray the darker color which covers over the lighter color overspray.

However, a better way, in cases where less paint is better and/or you want to spray the darker color first, spray the mask edge with a clear sealer. Designmaster makes a couple with different sheens. The clear then seals the mask edge reducing the bleed under.

For masking I've used newspaper sprayed with Spraymount adhesive on one side. The thin paper conforms well and the Spraymount adhesive is just tacky enough. Be light with the Spraymount and let it dry before using it.

Rey


Title: Re: Sweepette 36D -Build-
Post by: BG on January 27, 2010, 12:50:05 PM
Rey... that sounds like a nice solution. Next time!

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 27, 2010, 01:06:37 PM
WARNING!

If you make your birds too decorous, you will not want to hurl them into the gaseous miasma for fear of the inevitable scratches, holes, knarfs and dings that dear old Mother Nature has waiting for us all!!! :o

Leeper says. :P


Title: Re: Sweepette 36D -Build-
Post by: BG on January 28, 2010, 11:58:36 AM
;D ;D ;D Naaa Worries mate! This is nothing like the work I put into scale rubber models so I'll have no problem hurling this birdy.

Here are some pics of the masking process:

I designed the color scheme in Adobe Illustrator, then printed it out (sans color of course... ink is expensive) and then cut out the masks. I line the mask edges with glue stick making sure to get glue all along the edges. Then place the masks on the wing and stab and rub to ensure cohesion. Next step it to take my time and dust on several coats of DM red.

More tonight.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 28, 2010, 02:53:02 PM
I was only kidding Bernie. I know now for sure you are a GAMER!

BONSAI!

You also have a multitude of good skills. :)

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Randy Reynolds on January 28, 2010, 03:15:19 PM
"Bonsai" is a dwarfed tree and art in it's own right. Banzai!!!


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 28, 2010, 03:20:11 PM
THX for the defining moment, RR. ;)

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on January 29, 2010, 12:18:58 AM
Hi All,

Getting there now.

1st photo sprayed with masks in place.
2. masks come off... close up of edge... not perfect even though I tried to be careful.... no matter though I will be adding a black line to define the red-white contrast.
3. My two older kids with the demasked wing.
4. The wing and stab with decals in place.

Note for the decals I print my own on micromark decal paper using a laser printer (be careful to print only after the printer is cool... hot printing equals disaster). The decals are sprayed with a heavy coat of artist's fixative before use. Before decal application I apply a coat of solvaset to the surface so that the decal softens and sets into the woodgrain. Next I will put on a final coat of minwax and start the boom assembly. I may have to do some sanding to lighten the boom some before it is ready. BTW leeper...how much do your booms weigh in their raw form?

Last: I noticed the leeper mentioned lengthening the TMA to compensate for a less dihedral relative to Jugs I..... what is the theory behind this move? I ask because I think my tips are about 2 mm lower than the plan shows.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 29, 2010, 12:28:54 AM
That looks great Bernard! And really cute kids too!

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 29, 2010, 01:15:41 AM
Yeah Tony, Bernie has his own set of fetchermites like your nephew & niece! [or not...] Dittos to Tony's kudos on the appearance, too!

Bernie, I will have to make a guess at the raw boom weight, as I buy Stan Kits remember? They come with generic bodies that have boom attached and hinged to pod. Ready to roll after sizing and shaping, you see. I have a slightly bigger carbon boom that weigh 5.5g from another source. So my best guess is Stan's weigh 4.5-5g @ full 24" length, tapering from .26>.188, which he sands some.

Not sure where you got the idea about boom vs d'dral changes from SW36D-1 to -2. As close as I can tell, both of them have same d'dral of 3.37/tip [23deg] and .91/main [5.5deg]. I did lengthen -2 TMA to see if recovery and glide might be better. My analysis is: yes to the recovery, and it likely helps the glide as well as longitudinal stability. [thanks to Prof Mark D for that tip! :)] Oh and the CG went rearward to 2.37"[60mm], which has opened up the climb spiral, getting higher than my shorter ones. A win-win situation so far. Keeping fingers crossed!

Finally, if your tip d'dral is down by that much, you might ultimately want to razor-saw cut near tip joint & crank it up some. Bob White told us long ago, " Dihedral is like money in the bank. You can seldom have too much"!

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 29, 2010, 08:57:10 AM
Just my 2 cents (which might be overstating it) 2 mm less dihedral is likely not going to be noticeable Bernard. I'd try it as is for now. You can cut it apart later if need be. I do, however agree with Leeper that Dihedral is (in the words of Doug Galbraith) "Cheap"! ;D It's hard to have too much, and most people use too little.

How did you end up with less dihedral by the way? If your span is slightly shorter than the plan dimensions, you might still have the correct angles. Might want to check that.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on January 30, 2010, 06:37:29 PM
Hi All,

Close to the finish line now...

1. Shot of my stab sanding jig in action.
2. Stab assembly jig
3. Pivot block sanding .... I used a piece of sticky sandpaper wrapped around my tapered boom a few inches down from where the pivot block attaches (to compensate for the thickness of the sandpaper.
4. Pivot block ready to attach.
5. The model ready for DT setup...still needs flourescent paint on the fin and tips. Francis modeling.
6. Another shot this time with Hele modeling.

Total weight is 71 grams balanced at 50% (9 grams of clay).

After the fluorescent paint, DT spring, sandpaper patches and wing counterweight etc. she will be 73 or 74 grams AUW.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 30, 2010, 07:00:17 PM
Very drool worthy, Bernie! :D

Just wondering where you got rid of the weight? ??? That is so light [even @ 75-80gms] you may want to add ballast for penetration & airfoil efficiency!

Do you see a trim session window any time soon?

Congratulations on this fine build job.

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: Tmat on January 30, 2010, 11:55:21 PM
Very, very nice indeed!

I think that even Leeper might want to paint one of his roundy tipped birds in such a manner after seeing this. Well, then he might not be tempted to hurl with impunity!

Tmat


Title: Re: Sweepette 36D -Build-
Post by: BG on January 31, 2010, 12:19:46 AM
Thanks Guys, I am quite pleased with how she looks... very "classic" I guess.

Lee I guess the low weight is due to the boom and using lighter wood for the fuselage core (?). The wrapped CF boom was 4.8 g after cutting to length. The fuselage assembly is 15g. I guess this works out to less nose weight which means she comes in light.

I still have another coat of minwax to add too so she will gain a gram or two from that as well. ready to fly weight will be in the mid 70s or so.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on January 31, 2010, 01:08:35 AM
Bernie, I see now where the lighter final weight diff is.

You had guessed 20g for nose wt, but only needed 9g so far.

That also is quite near my Badge timer version's nose weight, FYI.

Doing fine job.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on February 02, 2010, 02:57:51 PM
Hi All,

She is finally done...well 99% still have to rig the DT lines etc. I inserted the noseweight (10g) using the Tmat scale technique. cg at 50%

I airbrushed some fluorescent orange on the lower tips of the wing and stab... added .2g for AUW of 73.2 g. BTW... airbrushing is the way to go for sure guys. I did the airbrushing using badger frisket film for masking this was much better than tape or paper.

Last step... minwax coat number three over the whole bird. With that she tips the scales at 75 grams. When dry I am guessing she will drop down to ~74.5 grams.

So that is it.

Flight test time!! ;D ;D


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on February 02, 2010, 04:00:59 PM
Not so fast Brother Bernie! Where are the sandpaper grips on wing tip? They may weigh .5-1gr depending, then you must put balancing weight on glideside tip to achieve desired turn. So I am thinking OAW ~ 77gr if CG is spot on. You do recall that SW36D-2 has 60mm CG, which is slightly aft of your 50% current setting. Thus, if form holds, you may need to remove some slight nose weight.

All I am saying is: yours is light & will no doubt fly like a dream!! ::) ;D Heck, you may even end up adding ballast to speed up the glide for some conditions. :D Am anxious to hear of its trim sessions, & hey, if you had a tracker beacon, put it on that bad boy as insurance! :)

Did I say it is a beaut? There, I did! :P

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on February 02, 2010, 04:34:13 PM
;D ;D ;D Ha HA... yes of course you are right... a spot of sandpaper on the tip and 1.5 grams on the glide side will get me up to 77g. Might be able to ditch a gram on the nose to get to the 60 mm cg but will handle that later after first flights (I want to start with a safe cg).

How do you deal with tip weight? Do you make a cut out in the tip or do you simply adhere some lead tape to the bottom?

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on February 02, 2010, 05:17:30 PM
Bernie,

After determining which side is heavier [usually grip side] I use clay at first to trim circle size. Then after weighing the clay I add lead to equal in this manner: Using lead sheet [I have some 1/32nd], punch out some pieces with a paperpunch. Then punch wing tip with same punch. If punch does not cut clean holes in balsa I am sure you can make a hole to fit lead pieces. It may take a 2 or 3 bits stack to get the desired weight, then a drop of CA. If I need more I use lead foil.[think wine bottle seal lead, which I save after enjoying contents!]

Golf club lead works, but the lack of partaking of some good wine is less enthralling. :-\

Leeper


Title: Re: Sweepette 36D -Build-
Post by: ram on February 02, 2010, 05:24:53 PM
BG,

Have you run the DT timer yet? I'm hoping it works as good as it looks!

Leeper,

Both of my gliders have needed weight opposite the throwing tip. I'm thinking I might just go ahead and glass the non-throwing tip to protect against rash, etc. Might as well have some of the weight accomplish something? What do you think? Maybe that's what people are doing already, just not saying?

Rey


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 02, 2010, 05:32:42 PM
Looks very nice Bernard. I use lead tape for tip ballast that I obtained from Orville Olm (Gizmo Geezer gent).

What's frisket film?
Using the airbrush then, what paint did you use for Florescent color?

Tony
-the timer will run slow out in the cold you know right? ;D


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on February 02, 2010, 05:57:36 PM
Rey,

Certainly not bad idea to glass the glideside ear. Not seen anyone do that, tho.
Funny, I looked at my TLG fleet, none have ever shown scuff or tumble rash damage on that tip.

FYI: surprisingly, most TLGs seem to need fairly equal tip weighting when trimmed. The stab skew & rudder are doing adequate turning job, IMO.

Oh, is the DT timer home-made with Silly-Putty inside?

ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on February 02, 2010, 06:36:12 PM
Ahhh... wine cap foil... excellent, yet another excuse to crack a bottle soon ;D ;D

DT:... sadly no I have not tried her yet (yes home made with silly putty see 1st posts)... will soon tho. I am trying to figure a way to ensure adequate leverage on the arm so that she does not lock up on the cold days.

Frisket film is a tacky clear plastic film that you can get from any decent art store at $2.00 per sheet :o. It does do a nice job with an airbrush but with DM spray you would probably still get bleeding. In the future I am going to do every via airbrush... lighter and no bleeding due to finer mist. Will also do black last rather than 1st ::).

Paint: I used the stuff that the RC guys use for their lexan bodies straight out of the bottle (no thinning needed).

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on February 02, 2010, 08:20:29 PM
Bernie,

Have you seen Stan's solution for keeping viscous timers moving as the spring force lessens close to release? [Dare I tell you?] ;)

Cut a short [.06-.09 long] piece of 1/16th alum tubing, slip down to bottom of lever and crimp securely. This acts as a cam, to speed up lever slightly as it comes into its last 60deg or so. Quite reliable, as long as you put the release loop ABOVE the tubing shoulder! :o

Caution: calibration of tension can be frustrating to some, I find. I start long & light, then gradually tie knots in the line where it enters the wing hole[recall the alum tubing you might see at right-center of wing?]til the tension increases to give the desired DT time. See attached pix of my Pathfinder CLG for a closeup view.

BTW, I use rattle cans of the fluorescent Lexan car body spray colors for almost all my airplanes. Good stuff and not very heavy.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: Bob_Morris on February 02, 2010, 10:32:38 PM
BG - nice looking glider. Looking at your photos makes me want one.


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 02, 2010, 11:46:15 PM
Have you seen Stan's solution for keeping viscous timers moving as the spring force lessens close to release?

See below for a close up of what Leeper is talking about. It's just a piece of small aluminum tubing crimped onto the wire drive pin as Leeper described.

The other way to improve the cold weather timer performance is to increase the spring tension. There are several ways to do this. You could use a stronger spring (bigger wire diameter), or just stretch the spring further to increase the initial tension. Personally, I'd avoid Silly putty for cold weather. The smoothie style timer has much less temperature variation than the Silly putty type, but that's a bit late now eh? ;D

I've attached Jim Buxton's superb illustration for Stan's style of DT system just in case Bernard might need a reminder of the arrangement. Sharp eyes might note that it even includes the little bit of aluminum tube as described above :o.

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on February 03, 2010, 12:30:39 AM
or just stretch the spring further to increase the initial tension.

But remember to stretch it from the REAR, by shortening the line, as I mentioned. Stretching from the front... well, that would give LESS tension, & you would probably need a new spring soon after. ::) :o

And I must say I have used Button & Badge viscous timers for the same temperature consistency reasons Tony mentioned.

Bernie: a Badge will fit easily in your fuselage I wager. I have a spare, so if you are interested send PM.

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on February 03, 2010, 05:49:57 AM
Mornin guys... a badge would fit fine as you say and I may change over to it if my doodad is sticky ;D Just thought I would give her a try first eh? Lee if you can spare the badge then please send her along.... and thanks much.

I am hoping to get a chance to maiden this weekend ...wifewilling ::)

B


Title: Re: Sweepette 36D -Build-
Post by: BG on February 03, 2010, 08:05:17 AM
Bah!! >:(... rigged the DT this morning and of course the dang timer does not work worth a damn. Seems that the pull binds the timer tube against the wood, stopping it from rotating freely. I guess this was predictable ::). Options: fart around some more by shortening the timer arm etc. to reduce leverage and therefore binding or just reject the idea and go to a badge.

Will ponder this today and make the changes soon.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 03, 2010, 11:01:02 AM
Oops! ;D
Ah well, I'm sure you will think of a solution Bernard.

Have you seen the Steven's Aero putty timer instructions?
http://www.stevensaero.com/StevensAero-18in.-Free-Flight-Hand-Launch-Glider-HLG01-SA-HLG01-p-18965.html
Look for the download (it is a .pdf file) at the bottom of the page.

They show how they handle a putty based side mounted timer in great detail. Might give you some ideas?

The badge or smoothie is of course a better bet imo, but you may want to salvage what you have.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on February 06, 2010, 01:09:29 PM
;D DT problem solved... just needed more leverage. See photos.

For the skeptics a vid of DT function can be seen here: http://www.youtube.com/watch?v=7Qi4O63HWRw

Flight testing next.... all I need now is time... but alas I don't have any :'( :'(

She is ready to throw now at 77 grams with 50% CG.


Title: Re: Sweepette 36D -Build-
Post by: Olbill on February 06, 2010, 02:16:35 PM
Personally I think you ought to just donate that glider to the AMA museum and then build another one to fly.


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 07, 2010, 09:16:14 AM
Personally I think you ought to just donate that glider to the AMA museum and then build another one to fly.

Ahem, that would be the MAAC museum Bill. :o ;D ;)

Well done Bernard!

Tony


Title: Re: Sweepette 36D -Build-
Post by: Olbill on February 07, 2010, 09:47:07 AM
Well it could be one of those cross-cultural things.


Title: Re: Sweepette 36D -Build-
Post by: BG on February 07, 2010, 12:28:43 PM
Hi Guys, Is there a MAAC museum?? ;D

Don't worry She will be well worn soon enough. See these videos for my first test glides on a bitterly cold afternoon (yesterday):

 http://www.youtube.com/user/BernardGuest#p/a/u/1/Os-c1sBKUjM

It was breezy but I can't figure what to do with her.... seems to drop the inside wing. I am thinking of reducing the tip weight.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 07, 2010, 04:08:24 PM
Almost seems like she doesn't have enough declage. And you might also need to reduce the left rudder and/or add some more washin to the left wing.

And yes, there is a MAAC museum. I had been asked to donate my 2nd place F1B from 1991 World Champs to the Museum. I was still flying it though and wouldn't you know at a contest in Ontario (Eastern Canadian Open) I won an evening summer fly-off and everyone went out with me to retrieve the model and we couldn't find it! It didn't go that far really, and we had a great line on it, and a good signal from the tracker. But after the flyoff we went out and there was nothing there. No model and no signal. I think that it must have landed near a road and someone took it home with them. Never saw it again. Sometimes I think that I should have given it to the museum for safe keeping. Then again...


Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on February 07, 2010, 05:02:05 PM
Hi all,

Tony, thanks for confirming my suspicions I was also pondering more declage. Maybe also moving the CG back a bit? First the declage though.
B


Title: Re: Sweepette 36D -Build-
Post by: Hepcat on February 07, 2010, 05:06:08 PM
Tony

Very sorry to read of the end of the F1B. I am not going to spout any mawkish rubbish about it being happier wandering free than hanging in a museum – the museum is where it deserves to be, I remember how interested I was at the time reading about these three Canadians who had put in the work to produce a 'Wakefield' that was different, and probably better, than anything else that was around. All the information about the design was carefully documented right down to the dimensions and weights of every component. It is interesting that Tony's F1B stays in the mind whereas most of the World Championship winners since then seem to be 'same old, same old'; and when drawings of them are published they are little more than shopping lists for bought out components.  Still I suppose that is the good thing that comes out of this – even without the model the memory lingers on.

To get back on thread. About the 'Sweepette' Tony said:'it looks a bit short of decalage'. Before reading that I thought, she looks to be flying too fast. Same thing really. BTW Bernard a very pretty (and careful) build.

John


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 07, 2010, 05:52:00 PM
Thanks for the kind words John. A whole other thread could be taken up with the current state of FAI and what has been lost and gained from the availability of World Class ready to fly models....

Bernard, moving the CG back would slow down the glide, but not help with the tendency to dive in shown in the video. That's going to require the declage increase (which will also slow down the glide). The final declage will of course be determined by the requirements of the launch and transition. Then the CG can be fine tuned to create an optimum glide as usual.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on February 16, 2010, 08:27:54 PM
Hi All,

Got some more trimming done.... see http://www.youtube.com/watch?v=YDT7FG74Aig for a trimming flight. She looks good on glide eh? The second video is of a tip launch. On this one she went up into a huge loop came out and then floated for 50 sec before hitting a tree 30 ft up. would easily have managed 60 sec in my opinion. If I can get the launch tuned I will be getting excellent times out of this floater.

Early cold morning by the way.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on February 16, 2010, 10:51:39 PM
That looks much better! So what did you change from the first test flights?

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on February 17, 2010, 12:24:28 AM
Hmmm, I only see one video listed on your last post. Where do I find second one?

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on February 17, 2010, 02:10:11 AM
Hi Guys,
Tony, one full turn of the incidence screw ;D.

The other vid is under my vids... not much to see... only the launch and then lots of bouncing around. She needs less declage now to cure the loop then shift CG to get the float back.
B

http://www.youtube.com/watch?v=9WSwszTo8us


Title: Re: Sweepette 36D -Build-
Post by: Pit on February 18, 2010, 09:46:28 AM
Nice flight Bernard! Good to see (and hear ;D) that you're getting some good exercise. Will you make it to OPENSCALE this year?


Title: Re: Sweepette 36D -Build-
Post by: BG on February 18, 2010, 01:42:55 PM
Hi Pete,

Nope no openscale for me.... too busy and too expensive.

one day maybe :-\


Title: Re: Sweepette 36D -Build-
Post by: jswain on August 20, 2010, 07:42:45 PM
Bernie,
After determining which side is heavier [usually grip side] I use clay at first to trim circle size. Then after weighing the clay I add lead to equal in this manner: Using lead sheet [I have some 1/32nd], punch out some pieces with a paperpunch...... Leeper

Hi Lee,

Thanks for posting the tip weight hint. I was rereading these threads to see what the consensus was on TLG CG vs. decalage for my newly finished Maxima30 kit build. After only using decalage and trim tabs on my Cats, it had not even entered my mind to use the tip weight on the inboard glide/non-throwing wing to open and close the glide circle for any reason other than to equalize the wing weight.

Newly finished Maxima30 hand glides completed safely today, First tosses early tomorrow AM with a 50% CG and 7/32" decalage- we'll see :o

Burning up in Riverside,CA -john s.


Title: Re: Sweepette 36D -Build-
Post by: BG on October 24, 2010, 08:14:20 PM
Hi All,
Finally got a chance to upload some launch vids. go here...: http://www.youtube.com/user/BernardGuest#p/u/0/uuuPTgcL544

there are several sorry for them being sideways....

Obviously need to work on my launch technique.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on October 24, 2010, 10:02:10 PM
Bernie,
From what I could see, your arm should be farther behind you prior to starting your steps and spin. The main thing seems to be your elbow is bent just prior to launch. Both of those things are contributors to hooking the launches, as I felt your videos show.

I have been guilty of the same malady, & Ralph Ray brought me a cure all one day. A postal triangular mailing tube to slip over my arm so it could not bend! So keep practicing and you will soon be much better & having great TLG flying fun!

Leeper


Title: Re: Sweepette 36D -Build-
Post by: BG on October 27, 2010, 12:50:50 AM
Thanks Leeper... do these look better?

http://www.youtube.com/watch?v=WlXC4cLDPEY

Sorry for the crap light but it was overcast and below zero (that is why my throwing hand was in my pocket on the first one)

B


Title: Re: Sweepette 36D -Build-
Post by: Kit on October 27, 2010, 09:15:38 AM
BG,

Gotta admire a man who flies when it's 0 degrees (even though you are talking that funny Celsius stuff). Biggest problems we encounter down here in swampland is warping tails due to heavy dew and fire ants.

Keep it up!

Kit


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on October 27, 2010, 01:49:15 PM
Well Bernie, I also admire your getting to it in the freeze, but could not see anything of your launch...was there more than one? Never mind, as Kit stated: just keep at it!  

Remember the 'voice' in Field of Dreams? I paraphrase that here:
If you throw it, good climbs will come!

Leeper


Title: Re: Sweepette 36D -Build-
Post by: JonSayre on October 28, 2010, 12:43:35 AM
Bernie,

The last video was perfect! Your launch looks excellent, I think what is more important than everyone trying to do the exact same thing is that everyone does what works best for them. Everyone's body mechanics are different.

You and I both happen to be throwing with the PROPER arm (read the left arm!;D) so I would say the only thing that you might modify is how tight you wind your body's spring. If you watch very closely @ the video starting @ exactly 12-13 seconds if you can, try to slightly widen your stance and bend your left knee just a little more. Then between 13 and 15 seconds focus on really digging the left foot into the ground and pushing off with it just before release. With a stationary throw your left LEG and then TORSO will be providing all the snap during launch. The deeper you can comfortably wind the spring and dig that foot into the ground and push the more velocity you will get.

You still have shorts and a T-shirt on it can't be that cold! But what would I know? I wish I was there flying with you it sure looks like a nice field and a unique sky to fly under!


Title: Re: Sweepette 36D -Build-
Post by: BG on October 28, 2010, 01:07:25 AM
Thanks for the tips Jon... I was wearing long johns and had run 3 km to get to my flying spot so I was warm for a while but then got cold. At one point I could not feel my throwing hand and suffered an early release. That white stuff on the ground is snow.

I am gonna be driving down through the states next week and will try to get some more flying in during that time.

B


Title: Re: Sweepette 36D -Build-
Post by: BG on April 12, 2011, 03:30:57 PM
Hi All,
The snow has finally melted so was out with Swe 36DII today and wrecked her (spiraled in and broke the fuse and stab assembly). Anyway the wing is ok so I will have to make a new fuse and stab and try again.

More when that is done.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 12, 2011, 04:23:34 PM
Bernie,
Sorry SW36DII is in dry dock.

How come? A complete Diagnostic report is de rigoure on this FF Forum! Meaning: WHEN & WHY DID IT SPIN IN?

Was it on launch (like way left... I forget if you are rt or left-handed), or gliding when it crashed?


Title: Re: Sweepette 36D -Build-
Post by: BG on April 12, 2011, 06:20:19 PM
Hi All,
Lee requests a postmortem. I avoided this prior due to :-[. In short is was all due to my needing to fiddle with trim and flying in windy conditions.

I have been trying to get the bird to turn (the turn has never been great ... kinda floats off doing a large open circle.... one problem is that I have not had many opportunities to fly her in calm conditions so it is hard to say much with confidence). Anyway my most recent solution to the turn problem was to add a gurny flap to the rudder. I gave her a few tosses and the turn looked good (but in ground turbulence on a windy day). So gave her a full throw and got a spiral after a decent recovery... RC-DTed her out and carved some of the G-flap away. Tried again, and again a spiral (after a fair recovery), DTed her and carved more flap away. Threw again but this time had a poor launch and did not get to the DT button in time so she crashed.

Damage:
Pop-up boom broke off (the ply fuselage flanges gave way).
Fuselage split and broke away from the wing (clean break).
one side of stab snapped off and lost to wind.

Repair list:
Fix dings in wing
New fuselage with mods to house my RCDT (got any suggestions for how to do this??).
New tail feathers.

Other: I need to make a spare bird (so that I would have something tomorrow if it were calm).... any suggestions?

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 12, 2011, 06:54:37 PM
OK Bernie, on board here with ideas to get you back in air ASAP.

1. Why would it spiral in? If wing has unwarped surfaces, I fear the CG is too far back, hence decalage too small.

2. Boom & body fix should be easy. Put small screw in from right side to give extra security to ply sideplates & clamp things together while adhesive cures.

3. Make RDT space in pod: First, router out length, depth and antennae exit slot needed to fit RDT assy [servo, LiPo battery & Airtek board]. Remove sufficient sideplate length from launch side of pod to make width room for RDT bits[servo is widest item, no doubt]. Checkfit the bits and make a plywood outer plate [some carpenters call that a 'butch plate'] to restore pod strength to normal. Make hatch ala Stan to cover RDT pocket.

4. Wing remounting on pod and new tail feathers: No need to say more. I leave those to your know-how.

5. Second glider to fly: Send for new Dynamo Hum II kit from Stan and make new SW36D with RDT Stan body.

Or...start a new from scratch build thread! ;D


Title: Re: Sweepette 36D -Build-
Post by: BG on April 12, 2011, 07:06:21 PM
Thanks for tips Lee.
Not clear on the Butch plate... can't quite picture it.

As to 2nd bird: Would love to order from Stan but his RCDT fuselages are over $100. Beautiful I am sure but that is too much for my model budget so I guess I am stuck with another scratch build. ;D

b


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 12, 2011, 10:01:30 PM
Let's see, how to explain 'butch plate'...

OK, to put a wider component into a thinner width space, you need to 'bulge out the side'. Wrap your mind around that idea for a minute.

So... how do we accomplish the redo of existing item without starting afresh? Simple. Cutaway the sidewall, make new sidewall [called "butch plate"], which overlaps the existing wall safely.

You need to verify your inside width needed, and then shim butch plate out accordingly with more plywood.

If it was me, I would make accurate top view sketch of the pod as is, draw in all components to size, then calculate how thick your shim should be... if you need any, that is.

Of course for your second one, you can create the RDT compartment with proper wood sizes to match the parts. The boom/sideplates fit depends on size of the rear parts, so shimming or tapering pod wood are likely req'd.

You are welcome. ;D


Title: Re: Sweepette 36D -Build-
Post by: BG on April 14, 2011, 07:56:15 PM
Hi All,
So here is the progress on my new fuzz. Note that I have enlarged the fuse (taller) somewhat to ensure that there is enough wood to support the ply side cheeks. You can also see my RCDT installation which will be removable through the rectangular slot in the soon to be attached ply cheek. Also shown is how it will look when all glued together (tonight).

Comments welcomed.
B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 14, 2011, 10:05:47 PM
Well, very creative and nice job going on! [clapping here...]

I do like the deeper body... gets the stab lower, unless I miss my guess.

Query: What is the actuator? I can't quite tell from pix...
Pager motor? Some trick thingie [Tmat will like that... ;D] unknown to us earth men? ???


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 14, 2011, 10:27:18 PM
Earth men?

From the way you pick air Leeper I thought for sure you were extra terrestrial! ;D :o ;)

Tmat
-nice job Bernard!


Title: Re: Sweepette 36D -Build-
Post by: Big Paulie on April 14, 2011, 10:33:14 PM
Earth men?
From the way you pick air Leeper I thought for sure you were extra terrestrial! ;D :o ;)

Ah-men to that, my brother!

Last Sunday I was timing for Leeper -- both a treat and an education -- and we would be sitting there in our chairs BSing, not paying attention to the air. Then he would say, "This feels right," stand up, launch his CLG barely 75 feet in the air, and nail a max. And he did that at least 3 times. :D

On the drive home, I started doing the math, and realized I'd have to be 110 years old before I had that much experience... :(


Title: Re: Sweepette 36D -Build-
Post by: BG on April 14, 2011, 10:58:46 PM
Hi All,
Lee the actuator is one of the new super cheap micro servos (see: http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=11737 ).

They are ~$5 each (or for a pair on ebay). I buy em and glue em into the airframe. Then I merely shift the RX and battery from model to model.

This fuzz does not place the stab lower...I just added a chin and a forehead. Might go for a lower stab on the next bird tho.

B


Title: Re: Sweepette 36D -Build-
Post by: BG on April 20, 2011, 04:55:34 PM
So I have sanded the stab and fin (using the music wire jig method from Tmat). Will finish the sanding tonight and add 1st coat of Minwax.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 20, 2011, 05:15:57 PM
It always makes me cringe when folks put finish on before gluing the bits together.

Think about that sentence. Ask a woodworker: would you put finish on before assembly?

You know what his answer will be.


Title: Re: Sweepette 36D -Build-
Post by: BG on April 20, 2011, 05:34:14 PM
No worries Lee... will mask areas to be glued.

B


Title: Re: Sweepette 36D -Build-
Post by: barry111129 on April 22, 2011, 11:57:51 AM
Hello Guys,

First post. I have read old posts almost daily since February that are packed with so much information that I have had no reason to ask a question until now...

I was interested to see that BG had his Spiral in crash at almost the exact same time as I had one with a similar set-up. I built a Sweepette 30 (Thanks Mr. Hines for the excellent plan) and like BG, I added a trim tab on the rudder because it was not turning the way I wanted. I have been flying almost exclusively in still air (it has been doing 65-70 second easily and consistently) in the late evenings because it has been so windy here in Dallas. Last week, on an almost ideal afternoon I went to the local field expecting to find lift. On the first throw it started rising like a rocket, and soon after came spiraling down. Fortunately, there was very little damage. Here are my questions.

Did the trim tabs on the rudder have something to do with our crashes? Is there such a thing as a thermal that is too strong?(I used to fly RC as a kid (FF is MUCH more fun) and never saw a plane go up like that) And how should I set the glider up differently for thermals as opposed to still air?

I have read old post about trimming, but to me they all seem to say add a little of this, try a little of that, and definitely use a lot of hoodoo voodoo!

Thanks for your help,
Barry


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 22, 2011, 03:46:18 PM
Barry, glad you joined our little sourie of TLG posters here on HPA! And thanks for your kind words re SW30 plans, which Bruce Kimball drafted for me. He does fine work.

First, Mother Nature is more powerful than the washin tabs, so if your relatively teensy, little TLG birdie gets locked into one of her mini-twisters thingies, it will get taken where SHE wants to take it!!! Spiky thermics are like mini-twisters, and have more violent whirling & vertical velocities than 'normal' thermics do.

Just a few months ago, both Stan & I got our TLGs trashed in by same thermal, which turned into a visible trashmover soon after we had launched. I doubt any amount of added decalage or washin would have saved either of our flights from disaster.

That said, it IS likely the tab on fin had at least some culpability with your spin-in. In all my years flying and observing Stan & vise-versa, I do not think either of us ever used trim tab or wedge on fin for turn control.

We DO mount the fin against left side of tapered boom, which gives it a SLIGHT angle to aid counter climb forces, then bend fin TE a fine amount to suit climb, recovery and glide needs. Your tab may be too thick, causing it to have too much power at speed. You might try moving CG forward and going with more decalage as a test, to see if that helps. If the climb gets too loopy, then you were probably close on trim before or now that is.

Keep with the FUN events, OK?


Title: Re: Sweepette 36D -Build-
Post by: BG on April 22, 2011, 06:33:23 PM
Lee et al..... the tip of my swe36 is 16.9 deg. above the root. Is this optimal or should I cut and reset to 19 deg while I have the wing separated?

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 22, 2011, 07:24:46 PM
What does Leeper's plan say? I'd put it to the plan to start with.

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 22, 2011, 08:11:54 PM
Excuse me, I have been away to see Mr Airtek for some electrickery RDT bits and repairs.

Yes, Bernie, check the plan and do what it says. I am not clear from your words what you mean.

Here are my D'dral values from log data on both of my SW36Ds, which matches the plan:
Mains=5.5deg or .91" above table per side.
Tips= 23deg or 3.38" with main flat on table.

I cannot see where you could get either of the values you quoted, if you followed the plan. ???


Title: Re: Sweepette 36D -Build-
Post by: BG on April 22, 2011, 08:32:43 PM
Hmmm ok... what I mean is that if you project a straight line from the root (lower surface) to the tip it is angled ~17 deg. up from horizontal. When I do this using your plan I get 16.5 deg. So I am a little above what you have on the plan. Since my wing agrees with the plan I guess I am ok.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 22, 2011, 08:50:49 PM
Check your Math Bernard. ;-)

Attached is the dihedral on the plan. The tip dihedral is 28 degrees above the horizontal. And I believe that Leeper intended 28.5 degrees above horizontal (I measured 22.6 degrees from the actual CAD drawing).

So I'm not sure where you get 16.5 degrees from?

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on April 22, 2011, 09:15:48 PM
Hmmm... perhaps were are talking past each other?? Here is what I mean. Hope this helps.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 22, 2011, 09:32:46 PM
Yes, our terms used had mutually exclusive definitions...non matching info!

Another thing... the SW36D plan you are using has been updated... slightly. ::) My file copy is current & has the angles and values I quoted priorly. ;D
It is a pdf file, so I will send it to you and Tony via regular email.

If Ratz wants it on Plan Gallery it needs converting file per his allowed type. ???

The only TLG currently so listed is SW30, which he helped me submit recently.


Title: Re: Sweepette 36D -Build-
Post by: BG on April 22, 2011, 09:39:31 PM
Ok look forward to the updated plan...

So bottom line is I am ok with dihedral as I have 17 deg by my method.

Will update with progress on repairs soon. May also start an 2nd SWE36DII.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 22, 2011, 11:51:18 PM
Bernard,
I don't look at dihedral that way, thus the confusion.

So, no confusion now.

Tony


Title: Re: Sweepette 36D -Build-
Post by: BG on April 23, 2011, 06:46:08 PM
Hi All,
So my repairs are near complete. Just some color touchups still to make and maybe a bit more minwax here and there. With the new slightly larger fuse and the repaired wing and new stab the AUW is 77 grams with the CG at 50%. So even after all of my fixes she is still very light for a 36D. Since I have had trouble with the turn I guess I will be adding a few grams of tip weight so that will help a little but I am also anticipating having to add some ballast.

Also, Lee will be chuffed to read the I am starting a second SWE 36DII. THe stab and fin are done and I have selected a piece of C grain for the wing. Some changes on this one will be a deeper fuse to accommodate the RDT system that I use and to get the stab even lower, and a new approach to the LE bass reinforcement. I plan to cut a slot in the LE into which I will glue a strip of bass. I think this will improve the durability of my LE. I also plan to tape the LE to improve durability. Lastly, I am thinking of trying Stan's foil but not sure if it is worth the extra effort to make the jigs.

Lastly: you guys add the dihedral numbers (center panel + tip panel) to come up with your effective dihedral number correct?

B

Bernard


Title: Re: Sweepette 36D -Build-
Post by: Hepcat on April 26, 2011, 04:16:49 PM
Lastly: you guys add the dihedral numbers (center panel + tip panel) to come up with your effective dihedral number correct?

No, Bernard, that is not the way an Equivalent Dihedral Angle is assessed.

As is generally appreciated if a wing with dihedral is yawed then the forward wing experiences an increase in angle of attack and the rearward wing a decrease which changes the lift forces on the wings in such a way as to restore the aeroplane to an even keel. The change in angle of attack depends on the angle of yaw and the dihedral angle of the wings and so for a particular angle of yaw the change in angle of attack depends upon the dihedral angle. If one is wanting to do some calculations on the dihedral effect then one takes the lift force, acting through the centre of lift of the wing panel, and multiplies that by the distance from the centre of lift to the CG which gives the rolling moment which is trying to restore the aeroplane to level flight.

The Equivalent Dihedral Angle (called the EDA in future) is a way of comparing the restoring roll moments of different polyhedral wings by comparing each of the polyhedral wings to a plain ‘Vee’ dihedral wing. This is done by finding the roll moments of each panel of the polyhedral wing and adding them all together and then finding the dihedral angle required on a ‘Vee’ dihedral wing that will give the same rolling moment.

The calculating task is not as arduous as it might at first appear because we are only looking for proportionality between one wing and another. For example there is no need to calculate actual lift forces as the changes in angle of attack give proportionate changes in lift. Also most approaches to EDA assume an elliptical lift distribution on the wing which gives major simplifications. Some people do try to calculate from actual wing panel dimensions but these, almost inevitably, will give worse results.

I am reluctant to offer you one of my spreadsheets at the moment because since I changed to Office 2007 there have been some peculiar things happening to my spreadsheets. I think Tony Matthews may have a ‘solid’ copy he could offer you. I am working on a new version at the moment to take into account the CG position. I think all the calculators around that the moment assume that the CG is at the centre of the wing, not above or below. This is pretty close for a glider but I realised it would affect results with near vertical tip plates and long wing posts as on indoor models.

John


Title: Re: Sweepette 36D -Build-
Post by: BG on April 26, 2011, 06:05:19 PM
Thanks for that explanation John,

I look forward to receiving a copy of the spreadsheet when you have it ready ;D.

Tony if you have one available I would love a copy of the EDA calculator.

B


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 26, 2011, 07:47:49 PM
Sure Bernard,
Send me an E-mail at: [email protected]

Tony


Title: Re: Sweepette 36D -Build-
Post by: Big Paulie on April 26, 2011, 08:38:47 PM
My spreadsheet only works one time when it's stored on my hard drive, then it freezes up. I keep Tony's email saved, and reopen the email and spreadsheet each time I want to use it. Works fine that way.


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 27, 2011, 11:54:45 AM
That's wierd Paul.

Maybe your machine?


Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 27, 2011, 02:54:53 PM
Just a thought... PLove suggested I add new 1 gig RAM [or ROM?...whatever] board when I had similar PC troubles. Did wonders. It cost less than 90 bucks including diagnostic/burnin testing. At Staples.


Title: Re: Sweepette 36D -Build-
Post by: Big Paulie on April 27, 2011, 03:27:17 PM
That's wierd Paul. Maybe your machine? Tony

I would assume so.


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 27, 2011, 04:35:56 PM
RAM Leeper. RAM is amazingly cheap these days. It's always good to have as much as you can squeeze into your machine.

Tony


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 27, 2011, 10:48:23 PM
THX for info on RAMming, Tmat. ;D


Title: Re: Sweepette 36D -Build-
Post by: Tmat on April 27, 2011, 11:53:53 PM
 :o :o :o :o


Tmat
-that Leeper, he's a card. And should be dealt with! ;D


Title: Re: Sweepette 36D -Build-
Post by: BG on April 28, 2011, 09:43:35 PM
Right! Back on topic me hearties... ;D

So here is a vid of the RDT mechanism in action: http://www.youtube.com/watch?v=_2uS5yvYnec

Also I provide photos of the repaired model and some close ups of the RDT installations etc. The new stab is ready and the model is balanced at 50%. It now weighs 80 grams ready to throw. She is also a lot cleaner than before; fewer bits out in the breeze. I will use a bit of tape to close the RDT hatch.

Now for some better weather eh?

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 28, 2011, 10:39:50 PM
Excellent Bernie! A.N. Other beauty from your glider creating shop!

I hope you can get a break with the weatherman soon, to fling it about.


Title: Re: Sweepette 36D -Build-
Post by: Olbill on April 29, 2011, 10:49:30 AM
Really nice job!


Title: Re: Sweepette 36D -Build-
Post by: OZPAF on April 29, 2011, 10:24:50 PM
Here is another EDA spreadsheet and a graphical method from Blaine Beron-Rawdon a modelling Aero Engineer, who worked on the Gosamor Condor.
They are slightly different in approach but as Hepcat noted they are for comparative uses only and this should be taken into consideration when comparing models.

I like your colour scheme on the SW36 and copied it on my small 12" CLG. The repaired model looks great.
John

Download - Calculation of Equivalent Dihedral Angle.doc (http://www.hippocketaeronautics.com/downloads/Calculation_of_Equivalent_Dihedral_Angle.doc)
Download - Guide Calculator eda1.xls (http://www.hippocketaeronautics.com/downloads/GUIDE_CALCULATOR_eda1.xls)


Title: Re: Sweepette 36D -Build-
Post by: BG on May 21, 2011, 07:06:15 PM
Thanks for the calculator...will try to put her to good use.

Went out to play with the SWE36 today...still having trouble getting a nice turn (even with a gob of clay on the wingtip). She just loves to float off on a very broad arc. Perhaps I will carve a bit of the washin tab off??

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on May 21, 2011, 07:53:19 PM
Don't think that is correct thing to do. You want a bit more glide drag turn, not less.
I would try more right rudder tab.
Most SW30s or 36Ds, also Tim's, Stan B's, etal, normally don't need much weight, if any, on glideside tip to fly properly.
As example, my rudder tabs are mostly about .06 to right at fin top. My washin wedges are stock size, ala Stan kits.
[2.0 >2.5 long, as I recall]
How is the launch/recovery going?


Title: Re: Sweepette 36D -Build-
Post by: BG on May 22, 2011, 11:47:01 PM
Hi All,
Took her out again today and had some success....I added a rudder wedge (1 inch long 1/8th thick) and got a decent turn. Did some launches and got ok results (trying to get the vids uploaded now). At the end of the session i threw the stab off. So my question....when I glue the stab back on do I add more skew (I think I had less than the 1/16th required) and or a bit of tilt (like my butterfly...which I frisby tip launch due to it being set to turn right). I figure one or both of these additions will allow me to ditch the rudder wedges.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on May 23, 2011, 01:05:59 PM
Yes.  More skew to meet 1/16 requirement and just a hint of tilt should not hurt.
My feeling is, tilt on TLGs is not as powerful as on a plane with bigger stab percentage.
That should allow you to delete fin wedges.


Title: Re: Sweepette 36D -Build-
Post by: BG on May 24, 2011, 08:39:05 PM
Hi All,
So I had sopme time with the bird today....the corrected stab skew seems to have solved the right turn issue so that is good news. My launches seem ok and I am getting used to the spin (? think? I will get some video next time so that my techniques can be evaluated). Now my last issue is getting the recovery tuned....I was getting a fairly consistent stall at the top which required a dive to half launch height before she recovered. I added some declage and this improved with some stalls and some good recoveries. I am guessing that a tad more declage and I will have a consistent recovery. This may result in a stalling glide however so I figure a forward CG shift might be required.

thoughts?

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on May 24, 2011, 09:12:46 PM
Again...Yes.  If your CG is per plan [2.25" or 57mm]as are mine, then you should be fine.
But a bit more forward is sometimes better, as the recovery will tend to swing and sweep
[pun intended] smoothly into glide.
Good to hear the skew fix seems to be rewarding you with better flights!

Practice, experiment, "wax on, wax off, Grasshopper!"  :D


Title: Re: Sweepette 36D -Build-
Post by: Rewinged on May 24, 2011, 09:22:09 PM
BG,

You can try different launch angles as well as playing with glider trim.  Also, different release timing will affect the bank at launch, which also affects climb and recovery.  I have only played with this enough to get my different gliders to recover well, not to optimize height.  I don't get enough flying time to try enough variations and keep them straight in my head.  I should probably keep a log.

Anyway, try different launch angles--you'll likely find an angle that will work with existing trim.  I launch a couple of my gliders quite flat--maybe 20 degrees up--and another up about 45 degrees.  A steeper launch angle will get you higher, but obviously not if you sacrifice too much recovery. 

--Bill


Title: Re: Sweepette 36D -Build-
Post by: BG on June 08, 2011, 10:43:13 PM
Hi All,
got my bird fixed after the dog stepped on the wing and snapped it. The repair went fine and we were out doing some flying today. The air was good and the wind was down. I managed to put her into a few patches of lift and got one great 6 minute flight where she climbed up to ~300 feet and just floated around gently. The other good flights were all over 2 minutes. This bird is able to really milk light lift and is good for 60-70 seconds in dead air. I am still working on launch technique...I am trying to emulate what stan does but I will need to record this before I can evaluate it.

My launches seem ok and consistent but I would wish for more altitude. The recoveries are generally quite good with no stall or loss of altitude.

Now my arm huts though....gotta get in shape I guess

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on June 09, 2011, 12:19:23 AM
Glad you got to let your bird out of its nest for some good flying!
Sorry about the arm pain...or is it shoulder? Strange, most never have arm trouble with TLG launching.
Unless possibly you are trying to more vertically pitch it, instead of more level.
I have heard of some such arm pain from those who tried that motion.
But you will find your way to TLG Nervana, I am confident!


Title: Re: Sweepette 36D -Build-
Post by: BG on June 09, 2011, 01:58:49 PM
Hi All,
Lee I am trying to keep things horizontal-ish, but I am not always consistent and one particular throw left me in some pain (slight shoulder muscle pull I suspect. Also the tendons in my elbow hurt (though I generally succeed in keeping the arm straight I do hook a launch from time to time).

Practice practice practice is the answer..
B


Title: Re: Sweepette 36D -Build-
Post by: BG on September 23, 2011, 01:33:36 AM
Production line for new TLG wings. Should have two new SWE 36DIIS in a week or two.

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on September 23, 2011, 01:51:26 AM
Query Bernie,
Will one of them have undercamber or not?


Title: Re: Sweepette 36D -Build-
Post by: BG on September 23, 2011, 09:17:26 AM
Ahh...good query!

I have started putting undercamber on one (the lower wing blank in the photo is nearly finished). I was thinking to leave the other flat just to see if there is a disernable difference. I am guessing that you would be interested in this experiment too  ;)


B


Title: Re: Sweepette 36D -Build-
Post by: BG on September 27, 2011, 05:14:45 PM
Update: both wings are nearing final sanding. Next step will be to add the dihedral etc.
b


Title: Re: Sweepette 36D -Build-
Post by: BG on September 28, 2011, 01:32:48 AM
Update: So just realized that both my wing blanks are thick...the foils are 9.5mm at the center and taper to 8 at the hedral break. Do i plane em down to 7.5 now? or do I go with the thicker foils??

One advantage is that the weights (45g and 47g) would get down closer to 40g (which my earlier version had).

Also one of the wings is undercambered and the other is flat bottomed.

B


Title: Re: Sweepette 36D -Build-
Post by: Rewinged on September 28, 2011, 02:38:21 AM
If it were me...

I wouldn't go down to 7.5.  Maybe 8.5 or 8.  I'd be tempted to leave it like it is.  My best Mumbo Jumbo--which is hard to beat--was over 52 grams after shaping, and gluing the dihedral, but before adding the dihedral braces or any glass or finish.  The SW36D likely has a bit less area, since it tapers earlier, and my MJ is nearly 4 7/8 inches root chord.  But still, your weights are very good, at least to me.

The 9.5 mm root chord is a tad thick from what I know for TLGs, but still doesn't seem like a particularly thick airfoil at 8.2% or so.  (Assuming 4.5 inch root chord + LE hardwood)

Re-reading your post, I see that the panels are down to 8 mm at the dihedral break.  I think I'd leave the center panels alone.

How much undercamber did you put in?

--Bill


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on September 28, 2011, 02:44:03 AM
Stop work until you answer this query: How much upsweep did you put in at LE?

If less than 1.5mm, increase to 1.5 or even 1.8mm.

Carry the greater upsweep value to the wing tip, or nearly as you can.

Then increase tip washout [sand or carve it] from tip d'dral line until you have about 2mm near the wing tips.

The weight will be less, but I see no worries if still over 45gms.

Good luck. Don't fret.

Bill has good thoughts as well.


Title: Re: Sweepette 36D -Build-
Post by: Rewinged on September 28, 2011, 03:01:17 AM
BG,

Looking back earlier on this thread, I was reminded that you had some launching issues and a bit of pain.  Though you're not a beginner, you might find my "TLG Beginner's Launch Guidance" a good refresher.  It has some stop-action sequences and video links as well as the text.  It's a few threads earlier in this forum at the present time.  Pretty basic stuff I'm sure you already know, but then again you shouldn't be having pain or trouble--and we want the new gliders to have a long soaring life!

--Bill


Title: Re: Sweepette 36D -Build-
Post by: BG on September 28, 2011, 12:07:41 PM
Hi All,
Bill I think I mostly solved launch issues and pain...my launches have been decent and fairly pain free recently.

Wings:

undercambered is 9.5mm thick at root and 8.9 at hedral breaks. Upsweep is 1.8mm. undercamber ~.6mm. I don't have room to sand in washout so will have to warp it in or skew hedral breaks.

Flat bottom is 9.8 at root and 8.5 at breaks. Upsweep is 2mm. Also no room for sanded washout.

thoughts?
B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on September 28, 2011, 12:52:46 PM
As a longstanding rule of mine, washout is sanded into each tip first thing.
Say, the last 15-20% of each wing half.
The above is in addition to washout gained by skewing the d'dral joints.

I feel & have found the use of both methods gives a more progressive and repeatable washout.

That said, if all else fails, cut bottom of tips at an angle from tip point to near d'dral break, bend up
to desired washout amount and CA glue in place.  Then do your fiberglassing of the launch tip.


Title: Re: Sweepette 36D -Build-
Post by: Rewinged on September 28, 2011, 12:59:29 PM
Leeper has the experience, but I will say that Stan's plans don't show any sanded washout, just the skewed dihedral joints.  Hence, my TLGs don't have any sanded washout.

The sanded washout--with the consistent tip-to-tip upsweep Lee mentioned, is lower drag, and hence has shown better performance for CLGs.  I suspect the difference for TLGs is more modest, but there should still be a benefit.  As I see it, the problem with skewed joints is that the tip might end up at negative angle of attack at high speed, which is very high drag.  But like I said, my TLGs only have washout from skew.

--Bill


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on September 28, 2011, 06:12:49 PM
Bill, etal,
You would only need to examine Stan, Ralph & my gliders to see the sanded in washout.

Some things that get done are not on plans.

Read between the lines here...


Title: Re: Sweepette 36D -Build-
Post by: Rewinged on September 28, 2011, 06:23:35 PM
Lee,

I believe in you, and in sanded washout.  My newer CLGs have it, and if / when I build another TLG, it will have it.

Just saying that my best TLG doesn't have it, since I knew even less when I built it than I do now, and it wasn't on the plan.  And as you know, my glider seems OK. :)  So if BG would prefer not to cut and glue, or sand some more, it can be OK.

Reading between the lines... (?)  one thing I am curious about is how much washout has been found to be optimal?  I just followed the plans for my TLGs, and guesstimate for my CLGs, and just asked Hannah re my P30.  There's always more to learn, so maybe you can share something about that.
 
--Bill


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on September 29, 2011, 01:35:06 AM
Re "how much washout has been found to be optimal?"
The answer is: Whatever works.
That means it is a factor depending on many design and trimming parameters.
You can sometimes trim around the optimum to achieve fair results, but making incremental changes
from plane to plane and especially on the same plane will glean better understanding of the beast.

Is that too Zen for this subject matter?  ::) ??? ;D


Title: Re: Sweepette 36D -Build-
Post by: BG on September 29, 2011, 01:49:07 PM
Hi All,
So i have warped in some washout on each tip. My technique is to use future floor polish at full strength. I soak the wood top and bottom at the tip and then weight the wing down over a washout wedge. I have gone for asymmetry (1mm more on the right than the left) because my birds go left.

Hope to cut and glass tonight.
B


Title: Re: Sweepette 36D -Build-
Post by: BG on October 06, 2011, 12:18:45 AM
Hi All,
So Jugs 1 has a new set of wings...flat bottomed and 10g heavier than the old ones (thicker foil and heavier wood). New AUP is 90g (92 with sandpaper strip and some tip weight).

Here are some photos...


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on October 07, 2011, 12:00:55 PM
As always BG, it looks great.  When will you put it thru its paces?


Title: Re: Sweepette 36D -Build-
Post by: BG on October 07, 2011, 03:59:09 PM
Hi All,
Lee....I will be at the Sierra cup (where I will make my Debut in F1B). I am tempted to bring her with me but not sure I wanna do my testing on that hard packed earth. It is too windy and rainy up here at the moment.
B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on October 07, 2011, 04:19:12 PM
Bernie, do pack her along!
My TLGs & I are nearly to LH BTW.
Bring gaters to fend off stickers or
socks will suffer!
NO FEAR!!!

Leeper




Title: Re: Sweepette 36D -Build-
Post by: BG on October 08, 2011, 09:40:56 PM
Ok Done,
Will have two gliders with me....
B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on October 17, 2011, 12:40:32 PM
I had the pleasure to fly our SW36 TLGs yesterday with Bernie[aka BG] at Lost Hills.
I can attest he did a very nice build,which has his RDT setup integrated nicely.
Plus it is flying better after a few minor tweeks.

Sorry we were too busy funflying to remember to take any pix!


Title: Re: Sweepette 36D -Build-
Post by: Hepcat on October 17, 2011, 03:42:13 PM
There has been quite a lot of talk about Washout in this thread and discussion of whether it is better to achieve the washout by slanting the cut at the dihedral joint or by sanding it into the wing panel.  I have never seen mention on this thread, or any other, as to the significant difference between what the two methods do.  It may be so obvious that no one thinks it is worth a comment but if there are one or two like me who did not realize the difference straight away then here are my comments.

As I understand it Washout is a gradual decrease in angle of attack as the tip is approached.  On this definition the slanted cut does not produce washout as it results in a sudden  change in angle of attack at the cut and that angle then stays the same all the way to the tip.

Aerodynamically I would have thought that the angled cut was a disadvantage in two ways.  First, I think the gradual washout is often appropriate to match a gradual change in wing section as the tip is approached.  Second, a sudden change in angle of attack (and therefore lift coefficient) at a slanted cut dihedral break will inevitable give a step in the lift distribution causing vortices to add to those already at the panel junction.

I suppose it must be acknowledged that slanting the cuts does make it easier to get both tips the same – if that is what you want. ;)
 
John


Title: Re: Sweepette 36D -Build-
Post by: glidermaster on October 17, 2011, 10:25:02 PM
A slanted cut is artificial washout in my opinion - for the reasons Hepcat gives, really. It works - no doubt about it, but there is a slight penalty doing it that way - that's what I think, anyway.
I carve actual physical washout into my solid HLG wings (as opposed to just a change in airfoil) - mostly just in the tips, but on my bigger models I carved it in root to tip. I like to apply a bit of the Ron Wittman style flare to the last couple of inches, too, but that is done by distortion. As I use lighter wood for tips, it's not a problem to do, but it is a bit prone to undoing itself, sometimes.
On a 24" (600mm) wing I wash the tips out by 1/16" or so (root to tip), then another 1/16" of 'Wittman flare'. On some of my better models I do the airfoil change thing as well. I gradually reduce camber towards the tip, and move the pos.n of max thickness forwards (as a % of chord) aswell.

I have to confess that some of these habits have little or no theoretical basis, but were adopted because doing the opposite caused problems. I have built quite a few HLG wings over the years. If I kept good records, like the Leeper, I'd know how many!

John


Title: Re: Sweepette 36D -Build-
Post by: -John- on October 17, 2011, 10:45:26 PM
...nice post Glidermaster...

John, it looks like the slanted cut washout method is for ease of construction. i.e. -one incorporates some washout into the wing without having to do a large amount of extra labor. You bring up a good point about the efficiency of the sudden angle of attack change though, as a more progressive washout would be desirable. I suspect that is why Lee also sands in extra wash on the wing tips of his gliders. Perhaps we should adopt the Mark Benns six panel wing with our slanted cuts to get a more progressive wing twist(?)(good for glide, maybe not so good for climb drag though). Just to add: the big glider Benn's flew here in the US for the nationals had a very nice glide once he got it trimmed properly for the conditions.

B, have you tried the Stanfoil on any of the new SW36 TLG's? Those are awesome looking gliders!


Title: Re: Sweepette 36D -Build-
Post by: BG on October 27, 2011, 11:53:28 PM
Hi All,
UPDATE: So I have had SWE36 out recently for test and refinement sessions and I think I have her fully tweaked. I was out in a stiff breeze today (~15 to 20 knots) and played with declage (reducing it) until I got her to start to spin in. I backed off a bit and now have a good climb and transition with a great floating glide. I played with the cg as well and now have her at 58%.

Washout....I have more warped into the right tip (1/8) than the left (1/16) for a left glide. Benefit??...not sure but this is what we do on scale rubber ships to get a nice stable circle and it seemed to work well on my scalded cat.

B




Title: Re: Sweepette 36D -Build-
Post by: BG on November 09, 2011, 10:01:40 AM
Hi All,
So here is my second SWE 36DII ready for final assembly (tacked together for the photos). Weight is 90g with everything including nose weight. The wing foil is flat bottomed. Also shown is the hatch for RDT etc.

b



Title: Re: Sweepette 36D -Build-
Post by: OZPAF on November 09, 2011, 06:38:13 PM
Thats art BG. I like your use of colours and the blending. Thats a level to aspire to.
Happy flying with it - the man(Leeper) may make a bid for it thats too big to refuse.
John


Title: Re: Sweepette 36D -Build-
Post by: BG on November 10, 2011, 02:01:14 AM
Thanks John, I am a lefty so this model is not gonna work for Lee....

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on November 10, 2011, 01:12:32 PM
Gentle readers,
For some reason I have not been getting 'notify' emails recently, so I apologise for not keeping up with the patter.
I will reply about canted joint washout[been doing it since my early indoor successes]and other related disiderata
when I can find time.

Ciao.


Title: Re: Sweepette 36D -Build-
Post by: FLYACE1946 on November 10, 2011, 01:27:23 PM
Congratulations  BG on the finish of the glider. Man alive that is one great looking color scheme.


Title: Re: Sweepette 36D -Build-
Post by: BG on November 18, 2011, 04:21:10 PM
Hi All,
Update on SWE36D ii.....first launches look pretty good but my nose construction which allows great access to the electronics etc. is too fragile for the rough and tumble of day to day flying. I will be reengineering the nose before I fly her again. Also the weather has turned here so flying is more or less off for now (snow and -20 deg.).

B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on November 19, 2011, 02:48:48 AM
Hello all you HLG aficionados,
I am glad you are carrying on these postings, which reminded me to reply as promised.

I am fairly sure I stumbled onto making canted dihedral joints to induce some washout even before I
had done a minute indoors.  I called it "Toe-out", as some may know.
It followed the same thought path as my use of offset & skewed wing mounting,by realizing that I, as
a human, could not build perfectly accurate & true, so I wanted to get surfaces started in what I felt
was the correct & proper flight direction.
It seemed logical that doing so would ease trimming, due to needing less tip weight, as well as reducing
some drag, since trim surfaces needed less tweaking to achieve proper flight modes.    
 
Going back to the learned 'Johns' [both 'Hepcat' & 'Glidermaster']posts of October 17, 2011:
I agree that washout is normally gradual from some arbitrary position, but beg to differ that it matters
to any noticeable degree whether it is imparted "suddenly" by dihedral joint skewing, sanding or warping.
As one might imagine, I have done all of those 'tricks', ofttimes even on the same HLG.
Keep in mind the cut angle is small[.06-.10"], & some chaps have done the math which determined
the washout angle imparted is quite small until larger cut angles are reached.
In fact, I have used .25" toe-out accidentally, with no detectable drag increase.

As the third 'John' rightly stated on Oct 17, I do sand in more washout in the last portion of each tip,
having done so since the '50s surely.  
I had learned from some great aeromodeller mentors that it was useful and "the best thing to do",
if one wanted to succeed.

Just to keep things in perspective, TLGs are still quite 'new' devices in the HLG genre, with much still
to be learned about what will make them really tick in the Future!

Thanks for listening.

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: roxy2 on August 20, 2013, 02:17:47 AM
 :) The weights that Lee provides for the wing,stab and fin ready to mount does those weights include
     the parts finished with Minwax applied?


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on August 20, 2013, 01:52:34 PM
Roxy2 etal,
The weights I posted (years ago) on page 1
are without Minwax coats added. I typically
 add finish after attaching all surfaces.
Also, the dihedral gussets(carbon is best)&
all fiberglass bits (glued on) have been added.

Hope that helps.
Leeper


Title: Re: Sweepette 36D -Build-
Post by: roxy2 on August 21, 2013, 01:48:03 AM
 :D Yeah that helps a lot Lee. I was struggling with the weight on the stab and fin thinking it included
 the finish coat. You guys were looking like Gods with the feather weights you are managing to get.
 Also my carbon booms are on the heavy side at 10 grams so having to carefully sand them back.
 One of them is down to 8 grams so far with room to take some more off without affecting the strength
 too much. What do u guys use to color the wings? It looks great.     


Title: Re: Sweepette 36D -Build-
Post by: Ployd on August 21, 2013, 11:04:45 PM
Roxy, I would hazard a guess that Design Master floral spray paint was used; from memory you can get it in NZ.

Ployd in OZ


Title: Re: Sweepette 36D -Build-
Post by: roxy2 on August 22, 2013, 01:53:52 AM
 :) thanks Peter, one would assume that the paint colors were applied before finishing with minwax.


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on August 22, 2013, 03:36:08 AM
Roxy2, there is no "hazard" in Ployd's guess as far as my color choice for gliders.
Primarily i use Design Masters, & AFTER two coats of Minwax.
Sometimes(often)I add bright fluorescent colors sparingly, as overcoat.
For example, Fluor red over DM yellow.
BUT, as I am quite sure, Bernie uses airbrushed colors which are mixed with thinner
or thin dope.  Maybe he will fill in the brand name.

Lasly, I would not lose a minute of sleep trying to save a few grams on a TLG.
They are quite tolerant in that respect.


Title: Re: Sweepette 36D -Build-
Post by: edwinzea on October 22, 2013, 05:04:19 AM
Hello Guys

I am staring my build of the Sweeptte 36d, I already got some good C-grade wood for the wings and a nice light boom. The plans are printed and ready to go.

I saw on an earlier post a "shaping" tool and I was wondering if someone could show me how to make them??

I am also wondering about the camber?? does it dramatically effects the performance of the wing??

Finally, I would like to build a couple of more of this designs and I was wondering if the "Tapered tube .200 dia down to .100 dia about 23" long" from MRL would be a suitable boom for TLG

Thanks in advance for the help

regards

EZ 8)

DLG scratch builder  :P

http://static.rcgroups.net/forums/attachments/8/4/2/4/2/a5631089-24-2013-03-20%2017.09.07.jpg


Title: Re: Sweepette 36D -Build-
Post by: -John- on October 22, 2013, 11:26:01 PM
edwinzea, in regards to airfoil camber; it is best just to build the model with a flat bottomed airfoil as likely shown on the plan. Incorporate a little bit of Phillips entry(upsweep) on the bottom, sand top of wing airfoil from the High Point to the trailing edge strait line, and shape the forward top portion of the airfoil as per plan, or as per the 'Stanfoil'. It is tempting to get carried away with airfoils on HLG's(at first) utilizing undercamber, but undercamber affects the pitching moment, thus the launch and recovery. Wing loadings on HLG's are not all that high, therefore the Flat bottomed type works very well... Plus easy to build.


Title: Re: Sweepette 36D -Build-
Post by: edwinzea on October 23, 2013, 02:31:18 AM
Hey John

thank you for your reply, I will follow your advise on the Flatt bottom.

regards

EZ  8)


Title: Re: Sweepette 36D -Build-
Post by: RCbobcat55 on February 07, 2014, 09:52:21 PM
 :)Hello from RCbobcat55  Very interesting build and discussion. Could someone point me to the plans for the Sweepette 36 model? I built a bunch of the original sized ones many years ago when Jimmy used to fly with us at a social hall near Freeport, PA. i have a large side yard (3 1/2 acres) and was thinking of building one and installing the as3x um system out of a wrecked micro ASK-21 foamy in it. I am always building chuckies for my granddaughter who lives next door to me and would like to try out the idea. Any help at obtaining the plans would be appreciated-they don't have to be full-size as my wife runs a print shop and can print just about anything i can come up with. Thanks much-I really enjoy reading the forum on free-flight even though my primary interest is in RC Sailplanes of all types. Keep up the good work RCbobcat55 my pm is [email protected] a pdf is fine if available..


Title: Re: Sweepette 36D -Build-
Post by: BEAR on February 08, 2014, 05:00:44 AM
http://www.hippocketaeronautics.com/hpa_plans/categories.php?cat_id=21&page=7


Title: Re: Sweepette 36D -Build-
Post by: Dave Jackson on April 08, 2014, 10:47:24 PM
Hi All

This is a thank you to all who provided info and build advice on the 36D DLG.

I have completed my own 36 DLG and it flies superbly. Although a little heavy 98g (due to tailboom being a sanded down arrowshaft rather than specialised boom) I get a still air time of around 70 sec.

The model flew off the board with no adjustments required thanks to all the relevant warps etc being already on the plan! Thanks Lee (and all those others involved) for a great design.

Cheers

Dave


Title: Re: Sweepette 36D -Build-
Post by: edwinzea on April 09, 2014, 02:23:33 AM
Nice plane Dave

My Sweepette is slowly but steady comming together. The first wing panel is now sanded 18.3g the second is ready to go. I hope to have it finished with some composite twists :D.

EZ 8-D
PS. pics coming soon


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 09, 2014, 03:55:42 AM
Dave,

So glad you are having EZ success with your nice looking SW36D!
(Ahem, all except the clay on right tip. U thought U could get that past me, but no, caught ya!  ;D)

Some Arizona DLG RC chaps are building SW36Ds, including George Morris, who has been high in F3K WCh ranks.
I am going to Poway, CA, May 3rd, for the Torrey Pines biggie, the International RCHLG Festival.
George will be there so we might get chance to chuck some SW36Ds around!

Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: edwinzea on April 09, 2014, 04:35:04 AM
I was looking at his YouTUbe chanel this morning and I was thinking, "well guys now you are aginst the #2 in F3K, lets see some launching tehcnique :P"

BTW this is the link to the chanel https://www.youtube.com/watch?v=_NdwM2S-b5s

Regards

EZ 8-D


Title: Re: Sweepette 36D -Build-
Post by: Fido on April 09, 2014, 06:09:35 AM
Leeper, what Design Master floral spray colors do you use mostly? I ordered a couple of bottles years ago, but I thought they wasn't as visible as I want them to be. It's hard to tell the actual color on a wing just by looking at a spray can...  :-\ I see that you have some good red color sometimes, that looks good. You also have a couple of birds with black as I record from you visited us here in Sweden, but what is that color named?


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 09, 2014, 11:37:50 AM
Hi Fido!

Good to see you here & 'speak' with U via HPA.
I commonly use three reds of Design Master(henceforth DM):
Holiday 714, Carnation 716, Cranberry 713.
Glossy Black 625 has some shine, even when mist-coating.
Glossy White 626 is nice for fin, nose & wing tip, for help to see
against dark side views, like trees & mountains.
The spray can color for me is quite accurate to the actual results.

Hope that helps U.
Ciao,
Leeper


Title: Re: Sweepette 36D -Build-
Post by: Fido on April 15, 2014, 05:00:39 AM
Thank you Lee, I thought the holiday red and thought it was nice. Anyhow, apparently new rules now since last time I ordered. It's not possible to send these can's over Air anymore, it must actually be shipped by boat. So, it's not possible for us in Europe to order Design Master Floral anymore.  >:(

/Fido


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 15, 2014, 11:13:56 AM
Sad Fido, but not surprised by that law.
Possibly you can locate an equiv @ a crafts or Hobby shop.
There are color concentrates which will mix with thinner for
spraying, if have a hobby spray unit.
If u were here u could have my older one!  ;D


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on April 15, 2014, 02:24:00 PM
Fido, it's called 'Oasis' in the UK. It may well be available in Swededn under another name. Try floristry suppliers?

Jon


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 15, 2014, 03:04:23 PM
Try to find CREATEX trademark Airbrush colors.
I have Fluorescent Orange. They are based in CT USA.
Not sure how many colors they make, but they must
have website info.
Water based & non-toxic, that product is dilutable in
thinner for airbrush use.


Title: Re: Sweepette 36D -Build-
Post by: Fido on April 17, 2014, 03:21:35 AM
Thanks for that information Jon, I'll have a look!  :)

Lee, I do have a bunch of Createx colors. Martin Beast have the gears, I usually go to him when using that stuff. And I like it! I have to buy me a compressor and an airbrush.  :P


Title: Re: Sweepette 36D -Build-
Post by: edwinzea on April 22, 2014, 07:41:06 AM
Ok guys, here is some progress on my SP36. The wing got already some CF tow on the LE and also a cap spar o the left wing. The tails are ready and the pieces fo the fuse are ready as well. I hope to have it finished for the weekend.

regards

EZ  8)


Title: Re: Sweepette 36D -Build-
Post by: -John- on May 01, 2014, 11:21:27 PM
looks good, have you had a chance to fly it?


Title: Re: Sweepette 36D -Build-
Post by: edwinzea on May 04, 2014, 04:07:34 PM
Thanks, I am actually not finished yet. I am building and RC DLG for the comming nationals :P so the TLG sits on the bench, only missing to finish is the fuselage

EZ


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on May 17, 2014, 05:12:58 AM
I'm seriously considering building a 36D but I'm not sure where to look for a half decent tail boom over here (UK). Any thoughts?

Thanks
Jon


Title: Re: Sweepette 36D -Build-
Post by: PeeTee on May 17, 2014, 07:22:14 AM
Jon

Speak with Mick P or Mark B. I know that Mick has bought booms from the USA, and Mark had some specially made for his DLGs.

A readily available alternative would be Mike Woodhouse's E36 boom. It's 8g unsanded for 32" and I would guess circa 5g when you sand and cut to length (remove the fat end). AviaSport Skinny kite spars are about 7g but I've had difficulty in finding a supplier in the UK. Another possible is the Skyshark 2PT, which is about 9g unsanded.

The FFS coupe boom is light, but I've found them to be very flexy.

Happy hunting

Peter
ps Mike is likely to take carbon booms (plus orders) with him to the Nats, so if you are going you can save the postage



Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on May 18, 2014, 04:54:36 AM
Thanks Peter, appreciate the info.
The SkyShark one has been used successfully by Ian M (and Mick gave his approval apparently  ;D)
Ian let me fly his new Butterfly on Friday and I've got the bug  8)
I have a lovely piece of wood sitting here looking at me too....


Title: Re: Sweepette 36D -Build-
Post by: PeeTee on May 18, 2014, 05:35:42 AM
Jon

The best priced 2PTs I've found were from here: http://www.kitingpoint.eu/product_info.php?pName=skyshark-2pt&mName=skyshark&products_id=859&language=en     I don't know about the shipping charge, but even in the UK it's pretty steep.

The Highwaymen kite store in Hinckley has them at £15 which might be better if you are local and can collect. I bought a job lot of 2PTs from the USA a few years ago for coupes, and in terms of stiffness the Woodhouse E36 boom is equally as good, and lighter. The Aviasport Skinnys have been advertised on Ebay at about a tenner for a 1M long boom. The choice is yours ;)

Peter


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on May 18, 2014, 06:16:38 AM
Thanks Peter. The E36 one sounds good then at a similar price for a one off.

I have a version of the plan (from the Discus Kid site IIRC) but is that the most up to date? Perhaps if Leeper is about?

Cheers
Jon


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on May 18, 2014, 10:21:42 AM
Jon, Leeper is about & replies in the affirmitive: yes, if plan is for SW36D2.
I think U will also find it on HPA plan pages.
Happy U R building one.
Mine still flies well, & if Wx permits, I might be flying it today @ comp in Lost Hills.


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on May 19, 2014, 03:38:41 AM
Thanks Lee, I've had my eye on one for a while  :)


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on May 28, 2014, 04:37:38 PM
Just wondering whether to invest in a razor plane? Until now I've managed small wings for CLG with chunky sanding blocks...


Title: Re: Sweepette 36D -Build-
Post by: BG on May 28, 2014, 06:27:07 PM
yes get a razor plane....indispensable tool for glider wings but also for trailing edge stock production.
B


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on May 28, 2014, 06:45:27 PM
Bernie is absolutely right.
My razor plane is my most indispensable tool!


Title: Re: Sweepette 36D -Build-
Post by: PeeTee on May 29, 2014, 02:54:28 AM
Jon

I third that. My personal favourite is the all metal 'David' plane.

Peter


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on June 04, 2014, 05:43:49 AM
Well I've got myself an E36 boom so I'm committed  :) Thanks for the tip Peter.


Title: Re: Sweepette 36D -Build-
Post by: BG on May 18, 2015, 09:02:24 AM
Hi All,
my complete collection of TLGs and cat gliders all for sale as is including a bunch of stabs and fins etc.

$200 for the lot.

Problem: I am a lefty.


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on May 18, 2015, 11:30:23 AM
Bernie, you can't imagine how sad this last post makes me...
But if those sweet birds find a nice new master, I will be elated again...


Title: Re: Sweepette 36D -Build-
Post by: BG on May 19, 2015, 01:37:21 PM
Don't be sad Leeper. Everything I sell gets me a little more out of debt. Maybe one day I'll be back : )
B


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on April 09, 2017, 05:46:49 AM
Finally looking at building a SWE36 again - please can anyone tell me where I can find the up to date version of the plan?

The one on Discus Kid http://www.discuskid.com/uploads/7/6/2/7/76278509/sweepette36d__1_.pdf
and here in the builders gallery http://www.hippocketaeronautics.com/hpa_plans/details.php?image_id=3796 seem to be the original version.

Thanks
Jon


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 10, 2017, 12:31:23 PM
Hi Jon, this is Sweepettelee replying to your query.
FYI, you have found the latest, up to date, all be it the original, version of SW36D, on discuskid page.
My only recommendations are that the fin was a bit large, so wait til you test fly it before adding the basswood strip.
Fin size is a critical item to achieve best transition to glide.
Also, the nose length might be shortened some if you like.
I hope you have one of Stan's TLG bodies to use for your SW36D. They are excellent and really assist the build.

BTW, yesterday I saw Stan's new one meter "Raven" TLG design fly.  He sez it is his best yet & I tend to agree!
You might want to inquire about it...

Ciao, LEEPER


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on April 10, 2017, 02:39:24 PM
Thanks Leeper. No it will be from scratch. Are the ply sides 1/32"?

I plan on picking your brains when I start trimming :)

Thank you!
Jon


Title: Re: Sweepette 36D -Build-
Post by: sweepettelee on April 10, 2017, 03:19:58 PM
I can't recall...I think 1/32 ply. 
Oh yes Jon! I just recalled...
Look thru HP's TLG subject matter and search for Jim Buxton's beaut exploded view drawing of Stan's body! That may be the ticket for you...
I do not have any TLGs left because I cannot fly them anymore. I strongly suggest you send future queries to Stan.
Even more strongly I suggest you simply buy his kits. 
I know you are in UK, but I bet that you have mates who travel to CA for comps who you could cadge into being a delivery person,
so you can order from Stan and have him offload the bits to whomever when they arrive for Fab Feb comps, etc.
Good Luck


Title: Re: Sweepette 36D -Build-
Post by: OZPAF on April 10, 2017, 07:55:50 PM
Quote
I do not have any TLGs left because I cannot fly them anymore.

That's not good news Lee. I hope you are well and could perhaps return to flying gliders again.

Cheers
John


Title: Re: Sweepette 36D -Build-
Post by: Yak 52 on April 11, 2017, 04:42:07 AM
Thanks Lee  :) you're still the guru so all help is appreciated :)
I've been flying radio DLG for a while now but my FF experience is limited to a few chucks (and hooks  ::)) of Mick P's Butterfly's. He has more or less given up launching due to back trouble too sadly. He's actually flying rubber these days :)


Yes the exploded drawing helps, thanks. I have some really nice wood here so hope I can do a decent version of the SWE36D with radio DT. In the long run I would like to design a large one as we dont have a span limit over here and when it comes to DLG I seem to be able to launch bigger models higher than light ones.

Jon