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Building Tips and technical articles. => Building techniques => Topic started by: David_Ruff on March 08, 2014, 06:06:47 PM
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Just opened the Brodak Ringmaster kit and it uses a Brodak wing jig in the plans.
Do I need to use a wing jig to build this?
Thanks in advance.
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It must be possible to build the wing without a jig, but it is easier to work on a jig because of the 3 piece LE and TE and a unusual center spar.
Last year I also built RM S-1. I made the wing jig with a cheap but flat wood board, two 8mm alm tubes and 1/8" lite ply.
Good flying, Aki
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Millions have been built without a Brodak jig. Just a flat surface and cobble some blocks together to pin it and hold the center lines of the LE and TE at the same height. And I know I'll get piled on for saying this, but that spar is unnecessary. All it does is gut the ribs in a hard crash. It's known by some builders of multiple Rings as the "Rib Ripper." I believe the survivability is better without it. And that wing is still plenty sturdy.
Rusty-bracing for attack.
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Millions have been built without a Brodak jig. Just a flat surface and cobble some blocks together to pin it and hold the center lines of the LE and TE at the same height. And I know I'll get piled on for saying this, but that spar is unnecessary. All it does is gut the ribs in a hard crash. It's known by some builders of multiple Rings as the "Rib Ripper." I believe the survivability is better without it. And that wing is still plenty sturdy.
Rusty-bracing for attack.
I am leaning toward no jig. I can find a way to get it blocked. That spar; was wondering about it. May build without it if it. Have to look it over.
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I am leaning toward no jig. I can find a way to get it blocked. That spar; was wondering about it. May build without it if it. Have to look it over.
I bought a 2 x 2 x 6 balsa block and cut it into squares with reference lines all at the same height. Drew a centerline on the inside of the LE and TE. Tacked the reference line of the blocks to the centerlines of the wing sticks and tack glued the blocks to the table with it all aligned. It worked great.
Here it is with my Sterling Yak-9 wing:
(http://i166.photobucket.com/albums/u116/rknrusty/Airplanes/SAM_2524_zps21c770d6.jpg) (http://s166.photobucket.com/user/rknrusty/media/Airplanes/SAM_2524_zps21c770d6.jpg.html)
I was lucky enough to have some shaped TE jigs from an old 1/2A Lil' Jumpin' Bean kit. They fit perfectly and allowed me to use their height to set the LE block heights. But they weren't absolutely necessary, blocks would have worked fine for the TE too.
Notice my wing is sans Rib Ripper.
I also doubled the center rib since I was going to use a shaker engine, a Fox Stunt 35. I just shot the paint today.
Rusty
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I bought a 2 x 2 x 6 balsa block and cut it into squares with reference lines all at the same height. Drew a centerline on the inside of the LE and TE. Tacked the reference line of the blocks to the centerlines of the wing sticks and tack glued the blocks to the table with it all aligned. It worked great.
This system may not work well with Brodak RM S-1, because the LE and TE are not one piece but 3.
Aki
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This system may not work well with Brodak RM S-1, because the LE and TE are not one piece but 3.
Aki
Yeah, that might complicate it. Reading back more closely, I see the second post mentions that. I must be one of the few people that's never built a Ring.
Rusty
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Millions have been built without a Brodak jig. Just a flat surface and cobble some blocks together to pin it and hold the center lines of the LE and TE at the same height. And I know I'll get piled on for saying this, but that spar is unnecessary. All it does is gut the ribs in a hard crash. It's known by some builders of multiple Rings as the "Rib Ripper." I believe the survivability is better without it. And that wing is still plenty sturdy.
Rusty-bracing for attack.
That piece of wood that you slid the spars on was really just a stick to hold the ribs in some sort of position to help you get the ribs into the L/E and T/E keeping the wing square. You then removed it. at least that is how a lot of the people that I knew did it and so I followed suit. it is not even an efficient way to ever spar a wing.
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I have built several of the S-1 Ringmasters, a Super Ringmaster and a scratch built Ringmaster. I left the spar in as when properly glued adds strength to the wing as far as twisting. Build the kit as the instructions say and you will have no problems. If you don't, don't cry when the wing folds on ya.
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...Build the kit as the instructions say and you will have no problems. If you don't, don't cry when the wing folds on ya.
I've heard that too, but at least for the Sterling version of the kit, my LE and TE sticks are so stout I could beat someone to death with them. Of course mine has yet to fly but I don't think the wing is in danger of folding. I'll come back crying and recant my advice if it does.
Rusty
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I used some scrap aluminium rectangular tube and cut it into small pieces and built the wing over them, shimming the LE and the spar...
Marcus
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That is different and looks like it does the job.
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The spar and the LE in this kit are the same size and have the same center line, so piece of cake...
A jig doesn't have to be fancy, just has to hold the parts aligned till the CA cures... LL~
Marcus