Gouging a Crescent of Aluminum Out of Dakota's Trailing Edge

[James L. Smith]

I'm trying to figure out how best to do this without dinging up the trailing edge purchased from Dakota Cub. The TE comes in two strips with screws holding it together in a sort of V-shape rotated ccw 90 deg, with two flanges folded over the V, closing it, and making it into a box. The 90 deg. flanges folded over the V are then screwed together with no. 4 by 1/4" screws-- in the forwardmost section of the TE when installed.

So, to install it on the wing, you've got to cut out slots in the V for fastening to the trailing edges of the ribs. N271T doesn't have flaps.

Anybody got any suggestions on how best to do this? Aviation snips, die grinder, band saw? Each method has its drawbacks in my experience.

We don't have a milling machine.

The die grinder works well for cutting excess length off the false spars.

And then I'm a stickler for deburring and round-filing a radius where a crack could start.

You should see the trailing edge being replaced if you want to witness a JB-welded mess full of cracks and decades of abuse.

 

[Snert]

I used a Dremmel tool and recall going through several bits. I wrecked one TE by trying to drill out a starter hole forthe Dremmel bit.

 

[R. JOHNSON]

James, on my trailing edge I used a drum sander in a drill press, I think about a 1" diameter drum. You just hold the trailing edge horizantal and apply pressure to the face of the trailing edge against the sander. This method worked well but there is still a need to clean up the edges of the hole w/ sand paper and/or round file, the end result pretty much duplicates a Piper cut out.

Ryan

 

[Flapman]

We use a milling machine here, but that's not a solution for you. A pin router works well, dip the bit in WD-40 frequently to keep it from gumming up. Pilot hole and files works too. Don't try to drill a hole that is more than about half the width of the overlap. Don't apply very much pressure when removing metal, whatever method you use. Support the TE very well in a vise (firm, not clamped hard.
You can figure a way to apply pressure along the length, remove the screws, cut out with a nibbler, re-squeeze, and re-screw.
However you do it remember that when the rib holes are in, the TE is very tender around the holes, it is easy to kink there.
If your TEs are longer than you need you'll have a little bit to practice on and perfect you method. I've got a pile of short pieces I can send you if would like.
Regards,
Flapman

 

[Steve Pierce]

Next time buy them from Univair and you will save yourself some time and aggrivation. They are already notched. I had to order blanks for the Clippers I am rebuilding. The drum sander sounds like a good isea. I am going to try that.

 

[coder]

for future reference

Dakota Cub supplies punched as well as un-punched trailing edges that are modeled after pipers. The reason the un-punched trailing edges are sent out is because there is no guarantee that the rib locations are the same as pipers, this way you can place the holes in any location you need to. (Some of the ribs i've seen are up to an inch off in either direction.)

If you specifically ask for punched trailing edges, they will be more than happy to send them to you.

I've also used die grinders, round files, and a 1" drum sander. It helps to have a long flat surface to work with and not to be too aggressive.

Coder