Bending trim tabs.... not happy with results :(

[danielhv]

I made my first attempt at bending the tabs at the end of the trim tab. I figured I'd start with the trim tab as its cheaper/easier to replace that the elevator should I screw it up. Im not really 100% sure what I did wrong... I tried to make the bend where the plans show... perhaps my wood wedge form was at the wrong angle of bend? Dunno. Here are some pics... let me know your thoughts/suggestions. The smaller tabs I bent with the blue plastic in place, so it looks like it dented the aluminum all up, but it didnt, all is still straight with no dings... i hope!

[SteinAir]

Don't feel bad. You're not the first and won't be the last. Thankfully there is a good solution that is elegant, looks better almost every time, and is easy!

Cut the ends off the actual trim tab itself (throw them away), then proceed to make yourself a little rib and rivet it in there. Looks good, finishes nicely and will be as strong as trying to get the bend perfect!

Just my 2 cents as usual.

Cheers,
Stein

[frazitl]

which I found to be a much cleaner solution. First, I cut off the ears on Van's part. Second, I made some small form blocks from hardwood to fabricate 3 mini ribs; one for each end of the trim tab, and the third for the "inside" of the elevator. Much more work, but I'm really happy with the result. PM me if you want to borrow the forms and blanks. Unfortunately I won't be able to send to you until early September (out of town 'till then).

[danielhv]

I would definately consider making these "mini-ribs"... Any pics on the final product? And maybe some of how you formed the ribs? I guess I'm having problems figuring out what angle to make this stuff at... I can cleco the part to the spar, and just guess what the angle is from the trailing edge to the leading edge, but have no idea for sure and usually means messing up several peices trying to get my guess narrowed down.

[danielhv]

Originally Posted by frazitl

PM me if you want to borrow the forms and blanks. Unfortunately I won't be able to send to you until early September (out of town 'till then).

That would be great, but what am I gonna do till then? Ill look around and see if I can find a way to make some in the mean time... if I still haven't gotten this done by September, I may seriously take you up on your offer!

[Norman CYYJ]

Before you make the next one try de-burring the edges first and also radius the ends of the metal. You should radius all corners on every piece through-out the entire plane as you build. It will relieve the metal of stress risers which can lead to cracks. Your trim tab doesn't look all that bad. Small ribs will make the ends look nicer but not make it function any better. You can also use the flush snap on your rivet gun to make the folds in the skin a little tighter but that takes a lot of care or you will end up with a big mess. Have fun and enjoy the build.

[L.Adamson]

If you have a sheetmetal handseamer, or buy one from Home Depot, you can bend the new rib flanges with it.

There is also a folding tool they sell. But I'm not sure if it has the 1" deep side to use for a 5/8" flange.

L.Adamson

[jmartinez443]

Originally Posted by danielhv

I would definately consider making these "mini-ribs"... Any pics on the final product? And maybe some of how you formed the ribs? I guess I'm having problems figuring out what angle to make this stuff at... I can cleco the part to the spar, and just guess what the angle is from the trailing edge to the leading edge, but have no idea for sure and usually means messing up several peices trying to get my guess narrowed down.

Don't make them, buy them. Here's what I did.

[ChiefPilot]

Heh - I made three trim tabs before I got it right. Doing it again, I'd do the ribs as others have suggested. While I'm really happy with how the final tab turned out on my project, it wasn't worth the time, aggravation, or expense.

[osxuser]

I messed up the bends on my skin, so I made a mini-rib for them, then tried bending the tab. It worked fine (a little better than yours, but good enough in my opinion.) so I used that bent one.