Metal fuel tank materials?

[MiTasol]

Both my Stinson and Fairchild use welded aluminum tanks. I've helped redo a BT-13 center section. The original sealing method was zinc chromate paste. Messy to deal with, but sometimes more forgiving than polysulfide sealants.

On a fleet of Swearingen Merlins I had the misfortune to work on in the 80's the very thin fuel inspection covers were originally held on with polysulfide sealant. Because they were thin and polysulfide sticks like the proverbial baby stuff on a blanket the panels needed to be replaced every 100 hourly as they were destroyed in removal. Then along came an acceptable alternative to use a specific Loctite product (515? 525? - thick red stuff - form a gasket or some such name). The panels never leaked with that, it was easier to apply (no mixing and a far thinner paste) and best of all the panels almost fell off once the attachment screws were removed. Magic stuff.

 

[cvairwerks]

On the F-16 we made all of our gaskets out of polysulfide. Vydex mold release is your friend here.

 

[MiTasol]

Sounds like an excellent option - I have never heard of it so it probably came out after I stopped swinging wrenches last century. (Lawd that makes me feel ooooowwwwlllllllldddd)

 

[GrauGeist]

Then along came an acceptable alternative to use a specific Loctite product (515? 525? - thick red stuff - form a gasket or some such name).

Sounds like Form-A-Gasket #3D by Permatex.

Good stuff

 

[MiTasol]

Sounds like Form-A-Gasket #3D by Permatex.

Good stuff

No but obviously I was thinking of that name wise. That is an excellent product but the Merlin sealant was Loctite 515 Master Gasket.

 

[YakMan]

I saw a YAk-11 for sale at an auction held at Kermit Weeks place. A friend of mine said, "Buy that, and put an Allison on it instead of that radial and you've got a pretty good copy of a Yak-3."

There are a lot of "Yak-3"s out there that are Yak C-11s! The C-11 is mostly a Yak-3 with a low-powered ASh-21 radial engine, two seats and some added bodywork to blend the radial diameter in. If you dismounted the radial and took all the add-on bodywork off (it unbolts!) you would be well on your way to making a Yak-3!