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Outdoor Free Flight Forum => Free Flight Scale => Topic started by: Don McLellan on June 11, 2021, 11:48:10 PM



Title: F4U Corsair
Post by: Don McLellan on June 11, 2021, 11:48:10 PM
Going to take a swing at a peanut scale Corsair, using my craft cutter.  Generally, the balsa is .040" thick, and quite heavy.  I've made no attempt to lighten the balsa with holes etc, but have to say, not sure why.  I think lighteng holes are quite neat.........maybe brain fade.

First pic shows some formers cut with my craft cutter.  Second pic shows some parts that have been cut out.



Title: Re: F4U Corsair
Post by: Don McLellan on June 11, 2021, 11:54:39 PM
The next pic shows my first attempt at gluing the fuse together, starting at the nose.  The second pic shows the less than stellar fuse former alignment, even with the 'pegs' (on the side rails) which should help to align the formers.

And yes, there is a fatal flaw.


Title: Re: F4U Corsair
Post by: Don McLellan on June 12, 2021, 12:48:56 PM
The formers in the first fuse attempt were a little random, so decided to make the side rails in one piece (first pic).  The side rails are connected at the rear plus at two internal cross braces (which will be removed later).  The second and third pics show the partially strung fuse and the nose. 

Currently building the wing, then will do some surgery on the fuse to allow the wing assembly to be installed.


Title: Re: F4U Corsair
Post by: Russ Lister on June 12, 2021, 02:00:27 PM
Following with interest, Don   :)
I use my craft cutter for vinyl so I'm a bit worried about the dust from balsa getting on subsequent vinyl cuts ... does it produce much?


Title: Re: F4U Corsair
Post by: Don McLellan on June 12, 2021, 03:13:54 PM
Hi Russ,

Yes, my cutter does produce both dust and the odd small chip.   

In addition to cutting balsa, I also occasionally cut numbers from vinyl for 1/32 scale slot cars.  No ill affects from the balsa so far.


Title: Re: F4U Corsair
Post by: Sky9pilot on June 12, 2021, 03:51:08 PM
Nicely done Don, and that cowl is great.  I shall follow with interest!  I built a peanut Corsair awhile back but have a larger one on the "To Do" list!
Sky9pilot


Title: Re: F4U Corsair
Post by: Russ Lister on June 12, 2021, 03:56:44 PM
Hi Russ,

Yes, my cutter does produce both dust and the odd small chip.   

In addition to cutting balsa, I also occasionally cut numbers from vinyl for 1/32 scale slot cars.  No ill affects from the balsa so far.

Thanks Don .... nice to know that it doesn't cause problems


Title: Re: F4U Corsair
Post by: tross on June 12, 2021, 07:05:58 PM
That's a great looking F4U Corsair peanut Don.
Also will be following.

Tony


Title: Re: F4U Corsair
Post by: Don McLellan on June 13, 2021, 09:02:01 PM
Thank you Sky and Tony.  The leading edge of the central portion of the bent wing is made up of 3 laminations.  Pic shows three laminations glued together (and a spare) plus the center spine of the wing.  All cut with my craft cutter.


Title: Re: F4U Corsair
Post by: DavidJP on June 14, 2021, 03:15:29 AM
Quite impressed.  What more can one say?  Some people have the ability to cut wood like that by hand - I would find that easier I think than understanding the mysteries of persuading a craft cutter to do my bidding, so not bad for a septugenerarian!


Title: Re: F4U Corsair
Post by: pedwards2932 on June 15, 2021, 08:46:30 AM
Do you ever cut thicker wood than 1/32?  I found with my cutter if I go to 1/16 and use the 60 degree blade I get drag marks as the blade crosses the balsa while cutting.  Do you just use the 1/32 and then laminate parts when you need thicker parts?  I still have problems getting the notches to cut cleanly which is why I moved to a laser....it will cut up to 1/8 balsa and does notches pefectly.


Title: Re: F4U Corsair
Post by: Don McLellan on June 15, 2021, 12:31:06 PM
Thank you David.

Hi Pedwards:  My craft cutter will cut up to .040" thick and this is the thickness of the wood I'm using for the Corsair.  One of the remaining hobby shops locally sells balsa labeled 1/32 but is actually .040" thick.

Have done some work on the wing.  Still have a few bits to glue, then sand the whole thing.  Then have to get the wing to fit in the fuse.


Title: Re: F4U Corsair
Post by: pedwards2932 on June 15, 2021, 01:17:30 PM
Do you use the 45 degree blade?  Mine will cut 1/16 with the 60 degree blade but you have to careful when fully extended as I said it will drag across the balsa.  I was never able to resolve cutting decent nothes on 1/16 but maybe it would work on 1/32


Title: Re: F4U Corsair
Post by: Don McLellan on June 15, 2021, 02:21:14 PM
Yes, I believe it is a 45 degree blade.  As mentioned, I can cut up to .040" material with this blade.  And agree, notches can be problematic.  When I cut balsa, I do it in several passes.  For harder balsa, sometimes up to 8 or 9 passes; softer balsa, 7 or 8 passes.  Also, when I draw the file, I extend the cut lines slighly past the corners, where possible.  This seems to help a little, making better, crisper cuts.  (Your mileage may vary).

Also, Tony Ross (tross) is an expert with these machines, so he may want to chime in.



Title: Re: F4U Corsair
Post by: Don McLellan on June 16, 2021, 12:14:50 AM
Weight of assembled wing, but unsanded is 2.57 grms.  Hopefully can bring that down slightly.  And weight of fuse and wing so far is 5.16 grms.


Title: Re: F4U Corsair
Post by: tross on June 16, 2021, 06:40:38 PM
That is looking good Don.
Can't wait to see it fly.

I can post a picture of a cut if OK.
I'm using a 30° for the thin wood and tape, 45° for the initial cuts on thicker wood, and a 60° to finish.
As far as the chicken scratches Phillip I'm just lifting the blade holder up in the carriage.
When cutting .10" wood I lift the initial blade up 1/16", and the 60° blade up .1"

The mickey mouse cutter was modified to cut thicker and it wasn't too difficult Don.
I can send or post some pics and basic instructions in another thread if it helps.
The picture below is of 1/16" wood so any size model you want to design and build now.
I'm not over-cutting the notches.
Everything is one solid polyline and converted to a block.
One block is placed under the drawing and one in the cut layout.
Any changes to design change the cut file section of the drawing.
Moving the cuts around is made more simply.
That TE in the jig is only .036".

Now back to the Corsair if you please and thank you... ;D

Tony


Title: Re: F4U Corsair
Post by: Don McLellan on June 17, 2021, 02:26:54 PM
Hi Tony,

Yes, please post some instruction regarding cutting thicker material.  Posting here is fine with me.  The only time I've tried larger than peanut scale models, using my craft cutter, is if I glue two of the same piece together (for a fuse former) to get .080" thick formers.  Glued former for my B-17 shown in the first pic.

Did cut open the bottom of the Corsair fuse to allow fitting of the wing.  The weight as shown is 5.59 grms.



Title: Re: F4U Corsair
Post by: tross on June 19, 2021, 08:48:14 PM
Will do Don.
Those bones are a swing and a hit ;D
Tony


Title: Re: F4U Corsair
Post by: Don McLellan on June 20, 2021, 12:15:26 AM
Hi Tony,

Thank you!  Have to say this has been quite an interesting build, mostly because I'm doing 'stuff' on the fly.

And I did get my second Covid shot today, so am typing a little slower than usual...............haha..............

I did add some diagonal stiffeners to the outer wings.  Have no clue if these are really needed for a peanut model, but they only added about .015 grms, so I think well worth it.


Title: Re: F4U Corsair
Post by: Crabby on June 20, 2021, 05:15:20 AM
Don, how did you come up with only 5.59 grams with all that lumber? That’s amazing, (a word I only use very sparingly). You are on track for a 9-10 gram peanut Corsair. Did you mention the plan you are using?


Title: Re: F4U Corsair
Post by: DavidJP on June 20, 2021, 06:52:17 AM
Ahh well you see Crabby Don is getting on a bit and had to guess the position of the decimal point.  It should be one digit to the right!


Title: Re: F4U Corsair
Post by: strat-o on June 20, 2021, 02:51:37 PM
You've got my interest piqued.  What version of the Corsair are you building? From the photos, I can't tell if this will be like a bubble canopy or a greenhouse canopy as in a F4U-1.  --Marlin


Title: Re: F4U Corsair
Post by: Don McLellan on June 20, 2021, 08:28:17 PM
Hi Crabby, 

All the formers, wing ribs and stringers are .040" thick.  Although it looks like a lot of lumber, it is still reasonably light.  It is a peanut, so that helps with the weight as well and the plan is by  Doug McHard.

Hi Marlin,

It will be the bubble canopy version.  I haven't yet made the buck for the canopy, so that will be interesting.


Title: Re: F4U Corsair
Post by: Don McLellan on June 23, 2021, 07:16:13 PM
Tail feathers more or less done.  The weight shown on the scale includes one small (required for assembly) clothspin.


Title: Re: F4U Corsair
Post by: MKelly on June 23, 2021, 09:04:22 PM
That's great Don, and very light for the amount of wood evident in the pictures.  Really pretty structure.

Mike


Title: Re: F4U Corsair
Post by: Don McLellan on June 23, 2021, 11:04:51 PM
Thanks Mike.  Now looking at how to cover it. 


Title: Re: F4U Corsair
Post by: Prosper on June 24, 2021, 04:03:51 AM
That's a lovely little thing Don. Does one need to be an IT expert to bridge the gap between a paper drawing or plan, and the delicate balsa shapes the machine cuts out? How is the required info fed to the craft cutter - USB link to computer, or memory stick, or whatwhich?

Stephen.


Title: Re: F4U Corsair
Post by: Don McLellan on June 24, 2021, 02:41:44 PM
Hi Stephen,

I'm probably the last guy who should be handing out info regarding 'how to' and craft cutters......................however:

I make an electronic drawing of the parts I want to cut out, then send this drawing to my craft cutter.  Note that my cutter plugs into my computer with a cord, so sending the info to my craft cutter is just a couple of key strokes.  My craft cutter is several years old.  The maximum width and length I can cut is not that big:  8" wide by 12" long.  Also, the maximum depth of cut I can make is .040".

Actually just remembered, my wife bought me a new, larger craft cutter for Christmas, but I have yet to open it.  (Old dog, new tricks etc...........plus brain fade......haha........).

Craft cutters will read file types other than DXF, but I have never tried using a different file type.

Tony Ross and others on this board are far more familiar with craft cutters, so please feel free to chime in.

Cheers,
Don


Title: Re: F4U Corsair
Post by: pedwards2932 on June 24, 2021, 09:17:15 PM
I use Inkscape for tracing parts......you can bring a pdf file into Inkscape and trace it to create a .svg file that my cutter can use.  Also if you are worried about the balsa leaving dust and balsa on your platen, I have made platen out of cereal boxes and they work....cheap alternative and you can toss them when they wear out.  Make them the same width as the factory one, draw a grid on it and spray with adhesive.


Title: Re: F4U Corsair
Post by: Prosper on June 25, 2021, 07:01:01 AM
Thanks Don and pedwards. Intriguing stuff.

Stephen.


Title: Re: F4U Corsair
Post by: Don McLellan on July 13, 2021, 06:15:30 PM
Apologize for the lack of progress on my Corsair.  My printer seems to have gone on strike, so can't print any tissue.


Title: Re: F4U Corsair
Post by: Don McLellan on July 22, 2021, 06:22:57 PM
Strike partially over.  Did manage to print some tissue.


Title: Re: F4U Corsair
Post by: PaulBrad on July 23, 2021, 11:41:43 AM
As usual Don, your Corsair and printed tissue are looking terrific.

Paul Bradley


Title: Re: F4U Corsair
Post by: Don McLellan on July 23, 2021, 02:51:42 PM
Thank you Paul.  Now have to get busy and install the tissue.


Title: Re: F4U Corsair
Post by: Sky9pilot on July 23, 2021, 07:54:38 PM
Looking forward to those skins being applied!  I know it will be fantastic!


Title: Re: F4U Corsair
Post by: OZPAF on July 23, 2021, 10:03:09 PM
Lovely looking structure Don.

John


Title: Re: F4U Corsair
Post by: Don McLellan on July 24, 2021, 09:16:42 PM
Thanks Sky, John.  Managed to get some tissue on the fuse today.


Title: Re: F4U Corsair
Post by: Sky9pilot on July 28, 2021, 08:35:53 PM
Looks great Don...as expected!


Title: Re: F4U Corsair
Post by: Don McLellan on July 31, 2021, 09:04:54 PM
Thanks Sky! 

As mentioned, my printer is on it's last legs, so the rate at which I can print tissue is determining the speed of construction of the model.  The first pic shows the wing partially covered, with a puncture wound in the tissue.  I did the old white glue and wax paper repair, and it more or less worked (second pic).

Third and fourth pics show the wing sitting in place.  I should have outlined the '850' on the side of the fuse to make it stand out a little better.


Title: Re: F4U Corsair
Post by: PaulBrad on August 01, 2021, 04:27:56 PM
Looking very nice Don. The tissue repair sure looks good in the photo.

Paul Bradley


Title: Re: F4U Corsair
Post by: alfakilo on August 01, 2021, 07:20:19 PM
...I did the old white glue and wax paper repair...

Can you describe this repair technique? I suspect it's something I will need to know!!


Title: Re: F4U Corsair
Post by: Don McLellan on August 01, 2021, 08:30:47 PM
Thanks Paul.  As per usual, a carefully posed picture can hide a thousand wrinkles..............

Alfa:  I take a small amount of regular white glue, dilute it with water (at least 50/50 but in this case it was something like 25% glue/75% water), brush the diluted glue around the area of the tear (not liberally but don't skimp either; the white glue should be visible around the tear), then place a small piece of wax paper over the tear, very very lightly smoothing out the glue around the tear.  Note that the smoothing is sometimes not required.  As the glue cures, it is attracted to the wax paper, and the tear is 'healed'.  Leave the wax paper for some time, say over night, then carefully remove the wax paper. 

Have made a buck for the canopy, but not really looking forward to pulling one. 


Title: Re: F4U Corsair
Post by: OZPAF on August 02, 2021, 04:20:49 AM
That's a very neat repair Don. Typical of your tissue work!

John


Title: Re: F4U Corsair
Post by: alfakilo on August 02, 2021, 05:52:47 PM
Don...thanks much for the info. I'll try it out the next time I poke a hole where it shouldn't be!!


Title: Re: F4U Corsair
Post by: Sky9pilot on August 02, 2021, 06:16:16 PM
Great looking buck for the canopy Don.  I love your tear repair tip.  Thanks!


Title: Re: F4U Corsair
Post by: DavidJP on August 06, 2021, 08:09:51 AM
Very nice (of course).  Don’t disclose the weight please. Just do not want to know. 


Title: Re: F4U Corsair
Post by: Don McLellan on August 06, 2021, 08:06:34 PM
Hi David,

Good to hear from you; I think the uncovered weight is around 7 grms, or maybe just under. 

Did manage to get the nose and the stab covered today.  And yes, my printer is still working to rule.  The 3rd pic shows where the nose will come apart for rubber installation and winding, and the 4th pic shows a little more detail of the rabbit on the side of the cowl. 

Don


Title: Re: F4U Corsair
Post by: OZPAF on August 10, 2021, 05:23:54 AM
I  like the bugs motif Don. Did you have any trouble getting good colour density when you printed it?

John


Title: Re: F4U Corsair
Post by: Don McLellan on August 10, 2021, 12:16:21 PM
Thank you John.  I had to fool around a little with the bunny motif, not so much regarding the density of the colour, but trying to get the blue the right colour (which is waaaaay off as you can see in the earlier pic).  However, and I've noticed this before, if the colour is close (in this case blue), a slight difference in shade doesn't seen to show up.  At least doesn't show up at Peanut scale.

As mentioned earlier, my printer is on its last legs and is now truly working to rule.  So I did try printing some tissue for the rudder using my wife's (newish) Epson ET-3760 (which doesn't use Durabrite ink), and it seems to have worked.  I glued the tissue to one side of the rudder, carefully brushed on some water to shrink, still had wrinkles in one area so really applied the water to that corner.  And, the tissue shrunk, but the ink didn't run.  As you can see in the pic, I used white Esaki, and printed both the blue background and the black lines.


Title: Re: F4U Corsair
Post by: PaulBrad on August 10, 2021, 04:45:16 PM
Everything sure is turning out nice Don.

Paul Bradley


Title: Re: F4U Corsair
Post by: Greg Langelius on August 10, 2021, 05:21:34 PM
I'm trying to do what you've done, and must admit to complete bafflement.

I have a new Cricut Explore Air 2, and no experience using it whatever. Three serious attempts to input parts panels from Flying Scale Models of WWII in our plans archive have simply refused to work.

I can glean neither the equipment nor significant parts of your technique from your posts here.

Could you be more specific?

Greg


Title: Re: F4U Corsair
Post by: Don McLellan on August 10, 2021, 08:38:22 PM
Thank you Paul. 

Hi Greg,

This is more or less what I do:

1.  Scan the model airplane plan, creating an electronic file of the parts, that can be imported into a drawing program.
2.  Import the scan into a drawing program, then draw over top of the scanned images to create CAD file(s) of the airplane parts.
3.  Scale (make larger or smaller) the parts for the size (wing span) of model being built.
4.  Arrange the redrawn parts to suit the width of the balsa being used; (could be 2", 3" or 4" wide balsa)....and usually more than one sheet is required.
5.  Import the cut files into the craft cutter.  Note that I make several passes with the cutting blade, depending on the density of the balsa.

Not sure if this clears anything up for you. 

Cheers,
Don



Title: Re: F4U Corsair
Post by: Greg Langelius on August 11, 2021, 11:17:07 AM
It does, and I'm grateful for your swift reply.

Thanks;

Greg


Title: Re: F4U Corsair
Post by: Don McLellan on August 14, 2021, 01:26:55 PM
Managed to slightly crumple one wing, breaking some internal bits (pic 1). 

My old printer has permanently gone on strike so used my wife's printer to make a tissue repair patch (pic 2).  The colour was slightly lighter, but beggers can't be choosers.

Installed tissue patch, and you guessed it, the ink ran all over the place (pic 3).  Interesting that the blue ran, but the black panel lines did not.


Title: Re: F4U Corsair
Post by: TheLurker on August 14, 2021, 03:46:37 PM
Sympathy.


Title: Re: F4U Corsair
Post by: OZPAF on August 14, 2021, 08:44:06 PM
That's annoying Don. I'm sure though that it will rise from the ashes :)

John


Title: Re: F4U Corsair
Post by: Don McLellan on September 23, 2021, 09:19:54 PM
Thanks John, Lurk.  Have really been dragging my behind on this one, however did make a prop and pulled a canopy.  Just have to glue the canopy in place.


Title: Re: F4U Corsair
Post by: OZPAF on September 24, 2021, 08:39:24 PM
I'm not one to speak of building speed Don :) it was worth redoing the problem areas - looks great.

John


Title: Re: F4U Corsair
Post by: Don McLellan on October 07, 2021, 11:44:16 PM
Thanks John. 

Nothing much to report other than I have made an attempt to fit the canopy to my Corsair.  I have some canopy perimeter tissue still to install, but thought I would post these pics, just for fun.  I left my camera in my car overnight, and the temp dropped to something like 6 or 7 deg C, so my camera was cold.  No big deal, except I brought the camera inside and immediately snapped a couple of pics.  As you can see, as a result of a cold camera and a warm interior of the house, there is some very slight picture fogging, which hides a million sins... haha...........

Cheers,
Don


Title: Re: F4U Corsair
Post by: OZPAF on October 08, 2021, 07:02:15 PM
Very artistic Don :D i must remember that one - close exam examination of my models is definitely not encouraged!

John


Title: Re: F4U Corsair
Post by: DavidJP on October 09, 2021, 06:16:56 AM
Yes and a lot easier than going at it with Affinity or Photoshop. Or applying “weathering”!  Nice anyway.  You do have a knack with these things.


Title: Re: F4U Corsair
Post by: Russ Lister on October 09, 2021, 07:41:45 AM
Nice work, Don  :)


Title: Re: F4U Corsair
Post by: Sky9pilot on October 11, 2021, 09:54:28 PM
Sweet...up to your usual outstanding craftsmanship!


Title: Re: F4U Corsair
Post by: Crabby on October 12, 2021, 01:21:48 PM
Great work Don.
that's a small model to be working on. I guess you still have the surgical moves, dexterity, and eye/hand coordination. I gave up neutering field mice a long time ago when I accidentally performed an adidicktomy on a male tse-tse fly!  ::) sttick with it professor!


Title: Re: F4U Corsair
Post by: skyraider on October 12, 2021, 01:39:08 PM
Late to the game but Outstanding work Don!

Skyraider


Title: Re: F4U Corsair
Post by: Don McLellan on October 12, 2021, 01:44:47 PM
Thank you for the very kind comments guys.  As mentioned, using a very cold camera in a warmish room hides a thousand sins.

Cheers,
Don


Title: Re: F4U Corsair
Post by: Crabby on October 13, 2021, 01:32:15 PM
so Don, what is your plan of action concerning trimming the F4U for rubber powered flight? I have heard tales from both sides of the coin, which worry me enough to stay away from this plane! forgive me if this question has been addressed.
also did you build in the thrust adjustment?


Title: Re: F4U Corsair
Post by: Don McLellan on October 13, 2021, 09:03:53 PM
Hi Crabby,

Right now my trimming method will be toss it and hope.  Well, will give it several tosses with the prop assembly removed and some clay in the nose to make up the weight of prop assembly, then adjust the angle of the stab to get some kind of glide.    After I get a reasonable glide, I'll try some power flights.  Recall my success criteria for flight is normally quite low:  10 seconds or 10 feet, whichever comes first.

And no, did not build in any thrust adjustment, other than 3 deg down.  Will play with this to get some kind of flight.  Also, will make the flight attempts with a two blade plastic prop rather than the wooden three blade currently on the model.  Our weather has changed quite dramatically (rain for the rest of the week) so not sure when the test flights will take place.  Hopefully before the winter monsoons start around here.

Don