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Author Topic: My first flying F1D  (Read 1174 times)
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ffadict
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« on: December 09, 2019, 08:12:29 AM »

Over the last year, I've slowly pieced together an F1d. It came out at 1.5g, and only had one major problem: it wouldn't fly. The smaller problems came from sloppy construction, broken spars glued too many times, and not enough boron reinforcement. I finished out that build rather discouraged in late October. In November I had the good fortune to come across https://www.indoorffsupply.com.


Several emails with the owner, Dave Lindley, boosted the moral significantly, and more importantly the supplies and tools department. Especially helpful is the Estate Wood section of his store. I was lacking some motor stick and rib wood, and it was an easy way to place an order (as well as reasonable at $5 a sheet). His business model is admirable, focusing on supplying materials not already available rather than competing with current suppliers. I highly recommend his store. Although not mentioned on his website, he's located in Chicago, so a plus for those in the US ordering wood. Anyway I'm reinvigorated and have begun a new F1D, which I anticipate being my first flying model of the class.


I've built some more jigs and have gotten a friend to 3D print me a prop block of the dimensions for Kang's Salt Jr. I'll be using this plan in all sections except the wing and possibly the rudder. These designs will come from his more advanced model (the extra rib in the Salt Jr. just doesn't sit well with me).


Anyway, I've made myself a pre-New Year's Resolution: finish the build before 2020. At this point I've built the motor stick and put some of the trimmings on it. I still need to attach the the rear motor hook to the MS, install the wing posts, and make the extension on it.


To make the MS I used a piece of .25" KS tubing and the motor stick form from Mike Kirda's excellent form set that includes the TB, ext., ribs, and the front and rear webs. It's fairly straightforward; just set the form over the balsa, mark the holes, and cut along the exterior. I, being a dunce, forgot that the MS form was 12" long instead of the required 9", presumably leaving the option for omitting the ext.. I managed to cut out the whole 12" length when I only needed the 9", leaving the rest of the sheet unusable for motorsticks...measure twice, cut once.


Once on a roll of destruction, it takes a lot to stop me  Grin I used some of the mini drill bit set I purchased to drill holes in 1/4" cherry fixtures to push wire through and support the motor stick as it dried in the oven. If you look closely in the picture, you can see three holes. These are where the remains of the 1mm, .9mm, and .8mm bits are buried  Roll Eyes  If at first you don't succeed, try try again didn't apply here. Note to self, skinny bits don't like to be hand drilled into hardwoods...But as to the actual motor stick, I can't complain too much. The weights of installed pieces is as follows:


MS Blank: 118mg
Seam Glue: 22mg (ouch!)
Boron Weight: 11mg (Yay!)
Pigtail Bearing: 20mg
Front Web+Glue: 13mg

Total MS weight minus posts and ext.: 236mg

Goal is to be 10-20% overweight

To put the boron on, I used a jig like one of them mentioned in the 2010 build log. I ended up tensioning it with a finger rather than a weight for more control. I have had some boron popping up, but have been ungluing it the rest way with acetone and then gluing the offending section. Then I add more acetone to the fine section to reactivate the glue, and press it back down. I understand what Kang meant when he said that while working with boron you should "be diligent". I diligently shoved a length of boron half an inch down my finger, and had it break off under the skin at both ends. Fortunately, it was close enough to the edge so that it could still be seen. Dad was called into action for surgery, and it was pushed out with a pin far enough to be pulled with tweezers.

Edit: The boron has continued to pop up despite my best efforts. Any tips on how to keep it down or why that happened in the first place?

I made the rear hook and pigtail bearing out of .013" wire, and had better luck bending than usual. On the rear hook, I cut out the web and bent the hook as close as possible. Oh then trimmed the web a little bit for a close fit. On both the pigtail bearing and rear hook I attached the web by wrapping it with kevlar and putting a small tissue bandaid overtop. This was a little overkill, but the kevlar was half of the thinnest thread sold on the thread exchange, sliced with a razor and then pulled apart. I would like to finish this build by 2020, so I've got a lot of building to do!


I haven't attached the rear web yet, but I'm very happy with the fit of the wire on the web. This level of fit was far superior to that of my building; this comes from a new trick I tried this time. I made the hook the best I could, and then trimmed the web to fit it reasonably well. I think this will result in an acceptable structure and will be stronger than if it had gaps and was the exact size originally intended (no material came off the top or bottom so it should still fit). I still need to put Kevlar thread over it, and possibly some tissue. On the front web I Kevlar wrapped and then added tissue as there was still some looseness with the Kevlar. This time around I split my Kevlar thread in two with a razor so I had extra thin stuff. I can't remember the original thickness anymore, but it was the thinnest stuff sold on the thread exchange.  


I think I should be done with the MS and ext. today, and make a start on the tail boom.
On a happy note, I'd thought I had lost this whole post, and rewrote it while I was out and about. When I came back to my computer, I found it still had the initial post up and I was able to copy and paste it even though it was no longer part of the web! Strange things...

Pic. 1: Workbench with new tools/wood
Pic. 2: More tools
Pic. 3: MS wood
Pic. 4: I'm looking at the piece stamped 00001 Micro X Ultra. Are these just multiple peoples stamps, or is this really the first piece of wood Micro X cut?
Pic. 5: MS drying jig
Pic. 6: The Love of Three Drill Bits (Prokofiev anyone?)
Attached files Thumbnail(s):
My first flying F1D
My first flying F1D
My first flying F1D
My first flying F1D
My first flying F1D
My first flying F1D
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ffadict
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« Reply #1 on: December 09, 2019, 08:14:24 AM »

Pic. 7: Boron gluing jig
Pic. 8: Boron popping up Sad
Pic. 9: MS weight
Attached files Thumbnail(s):
Re: My first flying F1D
Re: My first flying F1D
Re: My first flying F1D
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Crabby
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« Reply #2 on: December 09, 2019, 09:06:35 AM »

ffadict, I have long heard of the use of boron in indoor duration models but never had the guts to ask what its purpose is? I do know it can be hazardous if it gets broken off inside ones finger, in fact thats the first thing that comes to my mind whenever I hear the word. Anyway what is its purpose, what is the cost and where do you get it?
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« Reply #3 on: December 09, 2019, 09:40:10 AM »


Edit: The boron has continued to pop up despite my best efforts. Any tips on how to keep it down or why that happened in the first place?


You should always pull the boron using a weight or a rubber band to straighten it when gluing. I use rubber bands.

Aki
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ffadict
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« Reply #4 on: December 09, 2019, 09:44:53 AM »

ffadict, I have long heard of the use of boron in indoor duration models but never had the guts to ask what its purpose is? I do know it can be hazardous if it gets broken off inside ones finger, in fact thats the first thing that comes to my mind whenever I hear the word. Anyway what is its purpose, what is the cost and where do you get it?

I believe that boron is used as a stiffener for the balsa. It's brittle, so has very little give to it and seems to be stronger than the balsa. It's available at https://www.indoorspecialties.com for something like $18 per 100 24" long pieces. I think that it also has a sub-purpose of being used to brace fingers   Wink

You should always pull the boron using a weight or a rubber band to straighten it when gluing. I use rubber bands.
Aki
Hmm, that makes sense why it popped up. Maybe I'll try ungluing the popped up section to the end and reapplying it with tension.  
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« Reply #5 on: December 09, 2019, 09:53:59 AM »

The alternative to boron seems to be carbon fiber tow which is raw carbon fiber thread.  I too share crabby's visions of bits of boron circulating through my system!

https://indoornewsandviews.com/2017/11/20/substituting-carbon-tow-for-boron/
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faif2d
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« Reply #6 on: December 09, 2019, 10:36:27 AM »

My first F1D was test flown in my fathers haymow that was empty because the horses were long gone. They were not very successful but I finally got enough elevator (actually wing) angle in it that it did fly.
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« Reply #7 on: December 09, 2019, 11:29:25 AM »

Balsa and boron react differently to humidity. Balsa moves a lot in response to humidity changes. Boron hardly at all. It's pretty difficult to keep them joined if they're exposed to humidity levels that are different from when the boron was applied.

It's important to note that boron doesn't accomplish anything if it's loose and not very much if it isn't straight.

Tensioning the boron may accomplish getting it straight initially but doesn't guarantee it won't come loose if the balsa shrinks or expands.
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ffadict
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« Reply #8 on: December 09, 2019, 10:35:25 PM »

Thanks for all the boron thoughts here. I completely removed the boron on one side and replaced it due to a break that I made trying to re-position it. I applied it using the rubber band method this time. I initially glossed over the rubber band part of Aki's reply, but then it struck me this afternoon that it had mentioned rubber bands. At first test, it seems to work better for me than the jig I had made. No popups yet, keeping my fingers crossed. The other side hasn't fared too well. I might try replacing it too; the weight from the former replacement was only a 1-2 mg penalty.

It's important to note that boron doesn't accomplish anything if it's loose and not very much if it isn't straight.
Tensioning the boron may accomplish getting it straight initially but doesn't guarantee it won't come loose if the balsa shrinks or expands.

I know the first part all too well Roll Eyes The boron on my first airplane looped all over the place from me just gluing some popups to the side, and it did nothing for the MS but add weight. I don't experience very large humidity swings in Michigan, so I think that I should be good unless I start traveling to contests (which I hope to do in the future).

Carbon fiber tow...don't tell me that I need more supplies! I had enough trouble today. I was running out of polyimide tubing a couple of months ago and no one had it for sale anymore. I proceeded to request samples from a couple of companies, and ended up with one sample two weeks ago. I thought the other company had just ignored me, but today I received a 7.5' long package in the mail today, containing the tubing in 5' sections...mother was not happy. Enough supplies for the moment  Grin

Boron through the circulatory system...I wonder what happens when it reaches the heart Shocked
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« Reply #9 on: December 10, 2019, 05:24:57 AM »

Tow in the amounts you need can be very cheap. At least if you get it as tow rather than cloth. One possible source is Soller Composites. I don't know WHICH tow would be best. Maybe just get the scraps, cutoffs etc. that they list at $2/lb. But you can get spools of some other types for $18/lb. That ought to be enough for a number of F1D's. ;-)

I wonder if it wouldn't be better to split off little bits from pultruded carbon, which is nice and straight.

I'll admit I've had NO experience with boron or F1D. but I've seen the difference straighter fibers can make elsewhere.

It may help to keep in mind that some varieties of carbon fiber have a much higher elastic modulus than others. I think that may be more important than the somewhat lower yield stress,some of these fibers have.
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« Reply #10 on: December 10, 2019, 07:03:03 AM »

Just a few numbers to clear the fog about carbon tows. It may help to choose the right article for reinforcing your indoor model.

Carbon tows are normally called ROVINGS.
The distinguishing factors are type of fibre with different mechanical properties and number of single fibres forming the roving/tow.

The different types are called:
General, all round carbon fibre = NF, T800, if there is no specific annotation that's what you normally get as carbon fibre.
High Tenacity = HT
Intermediate Modulus = IM
High Modulus = HM
Ultra High Modulus = UHM

Tensile strength means the fibre resist high loads in traction, high modulus means the fibre is very rigid, but less resistant to traction.

The number of single fibres composing the roving is determining the section it forms together with the resin. The most found numbers are:
1k - 3k - 6k - 12k - 24k
The numbers are indicating thousands of fibres, 3k equal to 3.000 fibres forming a section of about 0,11mm2 dry and about double impregnated with resin.

Other parameters are "Elongation at Break" and "density" but that's a different story.

On indoor models the preferable reinforcing fibre is a high modulus typ to increase the stiffness of the single components disregarding the tensile strength.

Urs

PS: if I remember correctly Mike Kirda on propblocks.com sells small quantities of high modulus roving
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ffadict
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« Reply #11 on: December 11, 2019, 10:42:31 PM »

If I remember correctly Mike Kirda on propblocks.com sells small quantities of high modulus roving

I forgot to mention in my first post that Mike Kirda closed his store and combined with IFFS. At this point, carbon tow hasn't made it over in the transfer.

I used to think that F1D's were simple machines but hard to build. My impression is definitely changing...

I got the the TB and the offending piece off the MS. The ext. is rolled and drying. Weights of each and pics coming soon.

Paul
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« Reply #12 on: December 12, 2019, 01:45:11 AM »


One thing about carbon is that it comes in loose filaments (in both cloth and tow), and needs a matrix (some resin or glue) to bond the filaments together. Typically epoxy is used. This adds a level of complication in construction compared to boron. FWIW, I tried to make "carbon-boron" by soaking thin rowings of carbon (extruded from an uni-directional cloth) with celluloid glue, and attach these to a prop outline in a similar fashion as boron is used. However, the result was a disappointment - obviously celluloid glue is not hard enough matrix for the carbon fibers.

Having said that, carbon can be used for construction, but it takes more tooling and effort. I have build my latest F1D wing spars and ribs from carbon-balsa-carbon sandwich. Starting with the thinnest uni-directional carbon I have found (~10 grams per square meter if I recall right), I make a sheet of material, laminating the carbon on top and bottom of light balsa. For ribs this is done on a carved mold to gain the curve of the rib. After curing, individual ribs and spars are then cut out with a miniature table-top circular saw and a diamond cutting wheel. The issue with the thin carbon is that it is pre-preg - meaning that the fibers are pre-soaked with epoxy. This special epoxy needs to be heated (to 100 degrees centigrade) to cure, and to ensure proper adhesion I found that the laminate needs to be made in a vacuum bag. So you need vacbag that can handle the heat and an oven to heat the laminate for curing! The result, however is good, I feel that the wider carbon strip holds better to the underlying balsa than narrow strips of boron.
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ffadict
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« Reply #13 on: December 22, 2019, 10:01:30 PM »

Hmm, has it really been 10 days since I've done any modeling? Doggone work and school has gotten in the way(okay, okay, I admit that riding Herman, my 36" unicycle, ate some time too). However, I now have a completely empty week, devoid of work, with which I can F1diddle.

Today I did a marathon four hour building session (I remember reading that Kang built one of those ultralight EZB jobs in 20 hours over two days. Not sure how he managed to concentrate that long, but four hours was my limit). End result: a wing minus film and a frame to put the film on. Probably one of the few frames made out of cherry, but just what I happened to have lying around  Grin.

To build the wing I had a cardboard cutout to serve as a guideline. My wing didn't quite fit it because the ribs were .1" too long. I was too lazy to trim them down a second time, so the wing is slightly oversize. I'd like to fly at the Jim Richmond contest in March, but I don't anticipate my wing lasting long enough to make it there. The wing went together fine other than that, weighing 272mg. The overweight component there was the LE and TE. Combined, they came in at 145mg. I really need to get around to making a boron pre-gluing tool, or ponying up for one from Ray Harlan. Maybe after I save up for a rubber stripper...

Anyway, the boron on the LE and TE was partly what held up construction. I had one heck of a time getting it to go on straight without putting on a ton of glue and warping the balsa. I'm going to let it go at being a bit heavy this time, but I got a good tip from Dave Lindley which he attributes to Jeff Annis. A single fiber is taken from kevlar tow, and wrapped around the balsa. Acetone is brushed on to reactivate the glue, and the kevlar is held down, keeping the boron from popping up. I've got kevlar tow in the mail, something to try for the next wing.

I muffed putting the wing on the film. I managed to tear the film while I was trying to attach the wing, and ended up ruining it for something wing size. I suppose I'll still be able to use it for the elevator and maybe the rudder and prop, so not a huge loss. I was putting the wing on with the 10:1 Naptha and 3M-77, running the mixture along the film outside the wing. It looks promising, as I usually overspray the 3M-77 when using the spray on method, as well as leave more wrinkles in the film. I'll have to see if the method works tomorrow with a new piece of film.

As I write, this, methinks I overlooked a major part of the build. I forgot that I tacked together the TB. I've got a lot of pics and weights to put up, but I'll have to wait until morning to get them all up.

Toodlepip,

Paul
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ffadict
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« Reply #14 on: December 23, 2019, 12:23:01 PM »

Weights thus far:

Wing no film: 272mg
MS: (missing 1 boron and wing posts) 216mg
TB (w/boron) 175mg
Ext. (no boron, seam is glued) 37mg.

I'm not too far off the weights yet...just wait till I get to the prop though. I'm also working on a variable speed propeller mechanism, which I anticipate weighing 250mg for the first version, if it works.


Pictures:

1: I quite productively turned a clean desk to this in four hours
2: Wing tip form
3: Wing building frame
4: Oversized wing
5: Wing bones
6: Had to post a pic of this piece of wood for the ext. I've never seen one that looks quite this nice (source: Greenman)
Attached files Thumbnail(s):
Re: My first flying F1D
Re: My first flying F1D
Re: My first flying F1D
Re: My first flying F1D
Re: My first flying F1D
Re: My first flying F1D
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« Reply #15 on: December 23, 2019, 02:20:35 PM »

Looks great so far.
The photos are very instructive, shows the evolution of raw wood to something that will fly - thats what i love about model aviation.
Thank you for the tips on using the larger stainless steel nuts for rib alignment and paint brush for holding things off the table.
I'm looking forward to more, thanks!!!

john s.

ps- not so sure about the tractor seat for sitting though,  looks kinda harsh Wink
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ffadict
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« Reply #16 on: December 24, 2019, 10:25:34 PM »

I ran into some trouble yesterday. I went to weigh my wing after I put the film on (successfully after the third try I might add) and discovered that the wing weighed less with the film than without. Some checking with my 10g calibration weights showed that depending on the whim of my AWS Gemini 20, they weighed between approximately between 9.3g and 11.1g. Calibration proved to be futile, and an identical scale was promptly ordered. There doesn't appear to be anything more reliable less than medical grade, and that is a small fortune. So I have a new scale arriving Saturday.

Since the scale broke, I've completed the Ext. with the boron, I just need to attach it to the MS and then put the other piece of boron on the MS and attach the wing posts. That should finish the MS and TB setup, leaving the prop, stab and rudder. I've read about using polyimide tubing as the wing posts, and that might work for me. I've got a few sizes of it, including two where the interior diameter of one is .001" larger than the exterior diameter of the other. They have a nice fit, about the same as a standard balsa and polyamide fit. Any thoughts on just skipping the balsa?

Thank you for the tips on using the larger stainless steel nuts for rib alignment and paint brush for holding things off the table.

ps- not so sure about the tractor seat for sitting though,  looks kinda harsh Wink

Thanks for the kind words. I can't remember who I saw the nuts from, but they've been a great tool for two bucks. I couldn't figure out what you were talking about with the paint brush. I went back through and read my post, and still couldn't figure it out. Then I looked through my pictures, and finally figured it out. The pic of the wing on the scale looks like it's supported by the paintbrush. In reality, the wing is only touching the stand, not the paintbrush. But I'm happy if it gave you an idea  Grin. Re the tractor seat, my 17-year-old frame can take about anything. I've got a long time to figure our a cushier seating arrangement  Wink

Merry Christmas to all

Paul
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« Reply #17 on: January 07, 2020, 03:20:07 PM »

Phew, I kind of lost track of model airplanes over Xmas break. Friends and family got in the way  Grin Roll Eyes. I'm back at it now for a quick update and some questions, with more to come. I've built a stab form out of basswood, and seem to have good luck bending wood around it...when the wood is taller than it is wide. Every time I bend it around the way it's supposed to go, it flips back up and promptly cracks when I try to push it back. I've been soaking it in cold water overnight. Should I add anything to the water to help it go around?

I made the mistake of fiddling with the rib placement on the wing. I realized that one of the edge ribs was misplaced, and so I lifted it off. It peeled off of the film just fine, but as I was about to glue it down again I tore the film. I've got about a .5" tear facing inwards to do more damage  Shocked. Is it fixable, or should I start over?

I may have missed my December schedule for building, but I'll be attending the Jim Richmond Open in March. I'd better hurry up and get finished. I'd like to bring a couple of F1d's, maybe some Ministicks, and a Yelloise Manhattan Cabin (yes, I'd do a build log for that). If I somehow manage to build that, I might test the waters of A-6's...so much to build, so little time.

Paul
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« Reply #18 on: January 16, 2020, 12:20:10 PM »

Paul:

AWS Scale: while you may have a dud, I had on point in which I had erratic readings. Seems a small chunk of rubber slipped into the dogbone mechanism and was impacting the readings. I had to disassemble and blow it all clean.

Tear: only 0.5"? Cut a small scrap to overlap the tear boundaries by 1/2 to 1 cm. Use your thinned 3m77 and brush . Place the patch onto the tear area, it will stick by static. Then lightly brush the thinned glue around the edge of the patch, it will wick under. Too many of my kid's planes end up with a small tear before flying, so patching is an important skill.

Stab bending: We use scrap plexiglass (cheap from a plastics supplier, they always have a scrap bin) for our form. We tape the spar to the form after 5 minutes of soaking in water. We use blue tape with a strip of tissue (so the tape does not stick to the spar). If just wood, we then put it in the microwave t at level 6 for 3-4 minutes. For the stab LE and TE, we have started applying boron while straight, then forming. If you do this, don't put it in the microwave (it will be spectacular for a few moments, trust me). Put it in the toaster oven at 150-175 for 20 minutes, or allow to air dry overnight. And, for stab spars and tips, the wood should be vertical (taller than wide). For sharper bends (tips), be sure to push the wood around with your thumb, don't pull it around or it will break.

Chuck
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« Reply #19 on: January 16, 2020, 07:41:09 PM »

3M77 dissolved in even a great deal of acetone is too heavy.  Just use saliva as the bonding agent for film used in repairing tears and holes in the Mylar film.  Saliva has a bit of sugar and this is a good polymer bonding agent.  Some people suck on a bit of hard candy or take a sip of wine before using saliva for such purposes.  However, the top F1D flier of all time, Jim Richmond, has warned that any candy sucking or wine adds too much weight after the saliva has dried.

Also, saliva can be used as the bonding agent when tightening up the film after adding the dihedral to a wing or stab tip.  Again, 3M77 dissolved in acetone is too heavy.  Sometimes a flier may need to redo the film tightening after a while.  Saliva can just be reapplied.

LeoP
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« Reply #20 on: January 24, 2020, 09:24:57 PM »

Nuts, it's been a long time since I've gotten in any f1ddling in. Thanks for the input on the scale and the tear (over which I shed a tear). Glad to hear wine is too heavy, my parents might have a conniption fit  Grin. I've tried the saliva method for attaching film, but not for a patch. That sounds like it offers better luck. Apparently it used to work better on microfilm than it does on OS film. I'll have to see if disassembling the old scale and cleaning it doesn't work. I don't have too much to lose and I do have a replacement at this point

Stab bending: The wood should be vertical (taller than wide).

This makes it WAY easier! I wish I'd realized this before I chucked the first three outlines. I wonder how much it decreases efficiency to place the wood like this...but maybe the .015" difference doesn't significantly impact it (at least not at my level).

I've got the beginnings of my propeller and hopefully a torque and prop angle (makes it point up in later flight) changer mechanism that I'm fiddling with. Working with a 3d printed prop block is more accurate than a carved balsa one, but it's sure harder to get the wood to go where it's supposed to. I'm working on adding some cardboard forms to it to force the wood into place.

Thursday I'll be ordering a Harlan rubber stripper and boron gluer. Hopefully I'll be able to put them to good use. I've also got some rubber to test out from different vintages thanks to Skymon on the forum here. 

I was chatting with Ron Williams (I know, shameless name drop  Roll Eyes) and he said that some tips for a beginner at a contest were observing more than competing, asking questions, planning out flights, and trying to have a practice round beforehand. Anyone else have any tips they'd like to share? 

Paul
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« Reply #21 on: January 25, 2020, 02:09:34 PM »

Paul
Whe it comes to flying - record everything!
Make your self some flying sheets with the usual details and a nice space for notes.
Plan everything, make up some sets of flight data and fly those numbers.

I am terrible at flying sessions, I start methodically and then as the hours move on I get into tweaks and tweaks and I forget to note that changes.
It means that those flights are worthless really.

Don't be afraid to mark your wing/stab posts with a fine marker to show where your settings are - use a phone to take pictures of each post/surface interface position.

Write everything down - even the bad stuff.

Then set your self targets at your regular venues.

If you record your journey, you will enjoy it and you can repeat the results.
Happy flying Smiley
Si
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mkirda
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« Reply #22 on: January 29, 2020, 08:10:39 PM »

Pic. 4: I'm looking at the piece stamped 00001 Micro X Ultra. Are these just multiple peoples stamps, or is this really the first piece of wood Micro X cut?

You got the very first piece of graded wood from IFFS.

And BTW, Dave *DID* get all of my Toray M60J carbon. He just sold it all.
He knows the source. You might just have to bug him a bit to get some.

Also, there probably 50 people in the US who have it now. Ask politely. Someone might be willing to share some.

Regards.
Mike Kirda
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ffadict
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« Reply #23 on: January 31, 2020, 08:10:03 PM »

When it comes to flying - record everything!
Thanks for reminding me! I would've forgotten to do that when I finally get a plane in the air. I've got a file somewhere on my phone that is a handy sheet for recording such info.
And BTW, Dave *DID* get all of my Toray M60J carbon. He just sold it all.
He knows the source. You might just have to bug him a bit to get some.
Also, there probably 50 people in the US who have it now. Ask politely. Someone might be willing to share some.

Good to know. That's way out of my league right now. I'm still trying to figure out how to use a 3d printed prop block, let alone start using carbon-capped ribs and the like. I've got a rubber stripper and boron applicator ordered, so I'm waiting to apply boron and cover the stab before I come to any more head scratching on the prop. But to get a head-start on the problem, does anyone else use a 3d printed prop form and how do you attach the wood to it?
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mkirda
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« Reply #24 on: February 01, 2020, 10:48:23 AM »

The easiest way to do a wooden prop on a form is to wet it, put it in place, then wrap with tensioned thread.
I build it flat, glue on the ribs, then wet it and apply it to the form. I also use a marker to mark where it should be.

This way it holds it in place, but is still easy enough to adjust position. Once dry, you glue everything to the spar.

Blue tape pieces can also work, but lose adhesion to wet surfaces.
Thread is better as you can heat thread to really form the wood and not have to worry about the tape adhesive being too aggressive.
I always try to bake mine at 175F. This seems to be enough heat to form the lignin properly.

Regards.
Mike Kirda
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