Model Y AWD - puck size discrepancy

[fholbert]

Obviously, you don't know Baltic Birch plywood.

Historically, Baltic Birch plywood is stronger than steel or aluminum by weight and has been used in the original Wright flyer, Lindbergh's Spirit of St. Louis, and Howard Hughes "Spruce Goose." It use in the De Havilland Mosquito made it the fastest propeller driven plane in WWII.

All Higgins boats used in the D-day invasion and WWII PT boats were constructed of this plywood.

Yes. A DeHavilland Mosquito flew at my airport last month, I got a couple of pictures. Chino is know world wide for its war birds. IIRC, this wooden aircraft was the fastest bomber in WW II.

Thanks for the history lesson. I don't claim to be an expert in wood, but thanks for the history lesson. I've flown Citabrias with fiber wings. That doesn't mean I'll jack my car up using a similar construction.

I'd be interested in seeing strength tests for that material. 0.25 thick? I can find something similar for aluminum and steel.

Plywood won’t split. The grains cross each other.

Citabria’s have fabric wings, the spar is wood. What wood has over metal is, it doesn’t fatigue. Many high loading aerobic aircraft have a wood spar and wings.

 

[Mike500]

Thanks for the history lesson. I don't claim to be an expert in wood, but thanks for the history lesson. I've flown Citabrias with fiber wings. That doesn't mean I'll jack my car up using a similar construction.

I'd be interested in seeing strength tests for that material. 0.25 thick? I can find something similar for aluminum and steel.

It's 12mm thick. A half inch equals 12.7mm. Baltic Birch plywood is manufactured in Finland, Russia and the Baltic states from slow growth birch trees. It has tripled in price, since it cannot be legally imported from Russia because of the war in Ukraine.

Wood was the preferred material for fighter airplanes in WWI. During the later years, they switched to aluminum only because of the scarcity of plywood that could be had from Russia.

Baltic birch plywood contains 12-15% phenolic (Bakelite) resin. It often chars from the friction of the saw when cut.

It is the "carbon fiber epoxy matrix" of the 20th Century.