Wing tip sheet metal question

[shipljl]

I have a question about the sheet metal that transitions from the leading edge sheet to the tip bow. The upper piece of this has a riveted doubler that I can't see why it is there. It's present on both the left and right wings. Being a compound curve it wouldn't seem to be useful for stiffening, especially as the metal is already quite thick. Are these original? I may need to fabricate a new piece and I wondered if I should include this doubler.

Also, these pieces would seem to be far thicker than needed, adding a couple of pounds to the plane. Could they be made from thinner material?

Any thoughts?

[Larry Lyons]

Re: Wing tip sheet metal question

In my experience there are no doublers and the material is the same thickness from the root to the wing tip bow. My pre-war tip pieces are more then one piece unlike yours. Larry

[Ryan]

Re: Wing tip sheet metal question

I can't answer the question of their purpose, but I can tell you that both sides ofmy wings had them as well, and my project had one post war wing, and one pre- war wing. That piece was noticeably smaller on the pre- war side...

[astjp2]

Re: Wing tip sheet metal question

It keeps it from oilcanning...

[shipljl]

Re: Wing tip sheet metal question

Apparently there were two wingtip styles, a two piece sheet metal for the prewar, and a one piece for the post war (see the attached pics). Can anyone tell me which one was used on the in-between model 1941 BC12-65 deluxe?

[astjp2]

Re: Wing tip sheet metal question

That pic on the right is actually 4 pieces, my 41 was 5 pieces. I went with fiberglass to smooth the lines. The prewar leading edges were .012 material, mine were listed as SO for soft material. I replaced them with .020 T3. It adds a few pounds but allows you to lean against the leading edge when filling the wing tank or removing the snow. Tim

[guns68]

Re: Wing tip sheet metal question

I went with fiberglass to smooth the lines.

Where did you get fiberglass ones, or did you make them yourself?

[astjp2]

Re: Wing tip sheet metal question

I made them, I used the ribs to give the form and pulled a mold off the wing, then made the parts from the mold. Tim

[Hank Jarrett]

Re: Wing tip sheet metal question

My 41 and my 45 tips are like the first picture (actually two pieces joined at the leading edge). Mine was a late 41.
Hank