Plywood fuse screw-up fix
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Plywood fuse screw-up fix
I really should have seen this coming: I used CA to glue my fuse together and after I was finished I noted I had a banana - the side walls of the fuse were straight but while things were drying the bottom panel lifted at the tail by 1/4"(on a 31" fuse)- I still don't see where the stress came from. I'm going to chalk this up to the new experience that this hobby is: overcoming setbacks and never repeating the same mistake twice....or maybe thrice ....or maybe....
I tried to use a de-bonder to disassemble the parts to try again and found the CA is a very effective adhesive- so much so that the the formers broke as I separated pieces...and now I'm really in a bind to use the original pieces. Darn it.....mistake number 2
I figure that I'm going to have to cut new pieces, which to most experienced builders wouldn't be a problem....except that I'm not an experienced builder. So...........
I have a plywood panel that will become the new parts that I'll need to finish my plane. I'm going to re-do the entire fuse from scratch. I still have the plans so I guess it won't be that difficult.
What advice can any "real builder" offer that would simplify the cutting and shaping of the sides, bottom and formers.
Also, I've noted that the plywood I have (36 x 10 x 1/16)has a slight curve (<1/2") lengthwise. The wood at the local hobby shop was worse with nasty twists. Can I straighten this piece during the construction to suit my needs? Or am I heading for mistake number three.
Thanks in advance for looking and/or responding.
Ted
I tried to use a de-bonder to disassemble the parts to try again and found the CA is a very effective adhesive- so much so that the the formers broke as I separated pieces...and now I'm really in a bind to use the original pieces. Darn it.....mistake number 2
I figure that I'm going to have to cut new pieces, which to most experienced builders wouldn't be a problem....except that I'm not an experienced builder. So...........
I have a plywood panel that will become the new parts that I'll need to finish my plane. I'm going to re-do the entire fuse from scratch. I still have the plans so I guess it won't be that difficult.
What advice can any "real builder" offer that would simplify the cutting and shaping of the sides, bottom and formers.
Also, I've noted that the plywood I have (36 x 10 x 1/16)has a slight curve (<1/2") lengthwise. The wood at the local hobby shop was worse with nasty twists. Can I straighten this piece during the construction to suit my needs? Or am I heading for mistake number three.
Thanks in advance for looking and/or responding.
Ted
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Plywood fuse screw-up fix
Hi Shredz,
How I prevent this from happening in the first place is to use lots of clamps or rubber bands to hold everything in place, and glue a section at a time.
Use the panel or panels that original formers were cut from as a pattern to cut your new formers. Just trace inside the cutouts using a sharp pencil or use a very light coat of black spray paint. This uses the cut out panels as a stencil mask.
Now cut out the new formers using a scroll saw. Cut just in front of the the line. Then sand to the line using a sanding block.
I've found that if I spend some time looking at the "wreckage" (usually that what it is in my case ) formers and panels can be glued back together, without remaking the entire fuse.
Hope this helps,
John
PS Next time instead of trying debonder use an exacto saw between the seams to cut the misglued part free. Then reglue. Use triangle pieces for support where the tabs have been cut off.
How I prevent this from happening in the first place is to use lots of clamps or rubber bands to hold everything in place, and glue a section at a time.
Use the panel or panels that original formers were cut from as a pattern to cut your new formers. Just trace inside the cutouts using a sharp pencil or use a very light coat of black spray paint. This uses the cut out panels as a stencil mask.
Now cut out the new formers using a scroll saw. Cut just in front of the the line. Then sand to the line using a sanding block.
I've found that if I spend some time looking at the "wreckage" (usually that what it is in my case ) formers and panels can be glued back together, without remaking the entire fuse.
Hope this helps,
John
PS Next time instead of trying debonder use an exacto saw between the seams to cut the misglued part free. Then reglue. Use triangle pieces for support where the tabs have been cut off.
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Plywood fuse screw-up fix
Shredz:
John didn't address one important thing. Wood usually wil bend more easily one way than the other, and you say your ply sheets are already showing a bend. Use it. Cut out the new sides in a way such that the bend goes with the shape you want - this is simple too. Then, when you start gluing you can put the sides over the top view of the fuse, clamp, pin, weight it down, all things you can do to hold the shape while the glue sets.
Have fun.
One side curved, and one side flat:
. Hey, man, I Designed it like that!
Bill.
John didn't address one important thing. Wood usually wil bend more easily one way than the other, and you say your ply sheets are already showing a bend. Use it. Cut out the new sides in a way such that the bend goes with the shape you want - this is simple too. Then, when you start gluing you can put the sides over the top view of the fuse, clamp, pin, weight it down, all things you can do to hold the shape while the glue sets.
Have fun.
One side curved, and one side flat:
. Hey, man, I Designed it like that!
Bill.
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Plywood fuse screw-up fix
Thanks guys!
John: I tried using an exacto saw before I got to the debonder method sheesh, what a mess. If anything, this is going to be good practice for the crashes.
I really like the idea of using triangular pieces as gusssets to replace the tabs that are missing. I'll try to salvage what I can....if anything it would be a bit faster to rebuild. I've found the cutouts (now there's a a good idea!) for the panels in my scrap pile, and they're in good shape. If it looks like I'm heading for more trouble, I've always got the option.
Bill: I've "borrowed" my girlfriends' 3 lb ankle weights- you know... the kind that have some kind of shot inside a flat bag with straps on the ends? They'll be soft enough to not dent the wood and it appears that they'll conform to contours. I just might get a set for my toolbox..... if she misses them. If/when I do cut this plywood, I'll keep in mind your pointer about the curve...
As I think about it, I really wasn't prepared to start this project- I just didn't have the tools to do it right. I now have some small clamps that will help do the job nicely.......I guess I looked at the plans and thought everything would stay right where I put it as it went together....but I'd bet that lots of builders have had the same experience when they started out. The next plane will be a much better job.
A while back, I asked about fuse and wing jigs. I should follow through on those and build some. I'll get good at this yet.
thank you for you insights.
Ted
John: I tried using an exacto saw before I got to the debonder method sheesh, what a mess. If anything, this is going to be good practice for the crashes.
I really like the idea of using triangular pieces as gusssets to replace the tabs that are missing. I'll try to salvage what I can....if anything it would be a bit faster to rebuild. I've found the cutouts (now there's a a good idea!) for the panels in my scrap pile, and they're in good shape. If it looks like I'm heading for more trouble, I've always got the option.
Bill: I've "borrowed" my girlfriends' 3 lb ankle weights- you know... the kind that have some kind of shot inside a flat bag with straps on the ends? They'll be soft enough to not dent the wood and it appears that they'll conform to contours. I just might get a set for my toolbox..... if she misses them. If/when I do cut this plywood, I'll keep in mind your pointer about the curve...
As I think about it, I really wasn't prepared to start this project- I just didn't have the tools to do it right. I now have some small clamps that will help do the job nicely.......I guess I looked at the plans and thought everything would stay right where I put it as it went together....but I'd bet that lots of builders have had the same experience when they started out. The next plane will be a much better job.
A while back, I asked about fuse and wing jigs. I should follow through on those and build some. I'll get good at this yet.
thank you for you insights.
Ted
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Plywood fuse screw-up fix
I cant say that i have ever built a plane without screwing SOMETHING up. But thats the beauty of the materials we use to construct model airplanes- You can fix, realign or repair almost anything to be just as strong as before (if not stronger) without adding much weight at all.