Trim tab alignment

[Girraf]

I'll admit that perhaps I overthought this part of the build, but I really wanted to do this just once. I won't bore you with the details of what I found challenging, but here is my final result. The hinge doesn't leave you any room for fore aft movement of the tab if you want any hope of preserving edge distance on those hinge attach rivets. You basically need to drill directly down the centerline of the hinge flange. Overall, I ended up with exactly 3/32 gap on the outboard edge (min distance per the plans, which I can file open slightly), and well matched inboard edge, and the tab itself sits about 1/32" in from the TE of the elevator. Again, due to the hinge edge distance issue, I don't think I had much control over how this ended up. I'm curious if that's a passable result or if I should have done something different to get a perfectly matched TE. Here are some pics. I can always order some new hinge and try again....

Side note: my Wings arrived this weekend!

 

[wirejock]

Trim tab

Looks fime to me. If edge distance is met, build on.

 

[bjdecker]

Trim Tab mods...

After you finish up the elevator skeleton, skin, and put the bend in, tape/clamp a piece of 4' - 5' long AA3-3/4x3/4 to the left elevator trailing edge in the apex of the angle. Clamp a similar piece of angle along the right edge of the elevator, long enough to touch - or almost touch, the other angle.

Now position the trim tab using the two angle pieces. Provide a 1/8" - 3/16" gap between the left edge of the trim tab.

In my installation, I used the extruded hinge material (MS20001) with different halves -- P3 and P4 (I think) to give me additional edge distance.

Cheers!

b

 

[Girraf]

I did use a piece of angle iron clamped to the elevator TE to help with alignment. I suppose in the end, I chose to maintain 2D edge distance on the hinge holes instead of getting the TE to align perfectly. I'm wondering now if that was the better of the two choices...

 

[rzbill]

Girraf,
If memory serves, the flap hinges are the same way. You have to be spot on target with the hole positions to keep from busting edge distance on either the hinge or the airframe. Patience and accurate workmanship will get you through.

 

[wirejock]

Hinges

Girraf,
If memory serves, the flap hinges are the same way. You have to be spot on target with the hole positions to keep from busting edge distance on either the hinge or the airframe. Patience and accurate workmanship will get you through.

I recommen buying a section of the wider flange hinge for the flaps. Use 1/2 on each side. No hole edge distance issues. Also have a neat trick for drilling them. Check my blog.

 

[Girraf]

Well I couldn?t not call vans about this just to get their opinion. Talked to Mitch (as in the president maybe?). Anyway, he said if I could live it, then he could live with it. .

Roger that, moving on!