Brodhead Pietenpol Association

Hello all:

My question this time has to do with plywood, specifically 1/8” 4’ x 8’ mahogany I received from ACS. This plywood came with the “fuselage kit.” Very pricey nowadays so I expect good stuff. Ordered in OCT received in Jan and both pieces pulled apart easily with fingernails. I sent it back. They sent two new pieces and though they seemed a little better I could still pull whole sections of ply apart with not too much effort. The plies come apart at the glue joint. I assume the glue should be stronger and if the plies come apart at all it should be the wood tearing and not the glue. Am I being too picky with my delamination testing of the mahogany plywood? Is this normal?

Thanks…

I don't think you are being too picky. Plywood shouldn't come apart that easily. I only used mahogony in limited places. It took quite a bit to cause the surface plies to lift off. The force had to be applied perpendicular to a cut edge and even then caused modest chipping of the surface ply. Mostly I used Finnish Birch. The surface plies never lifted off with that material -- ever. Warning, though, Birch is slightly heavier than Mahogony.

You absolutely should not be able to peel those laminates apart. Plywood gets its strength from the laminations glued together in different directions. You have an inferior product if you can peel it.

My guess is bad manufacturing process, and all from that batch will do that. I'd try to get my money back and order from somewhere else. (shrug) What a PITA..
I ordered green epoxy primer from ASS, and it was white. Mislabelled. Told them about it and they sent me more white that was labelled green. Told them to open the freakin can and *look* before sending more..

Thanks for your comments. When I do this project, and things don’t seem right, I think, “Is it me? Am I doing something wrong? Should I not be trying to pull plies apart?” But then AC Spruce has been good about replacing the stuff (only with more bad stuff), so customer service has been good. Quality control has not been good.

Caveat emptor, but I was happy with the spruce beam that I ordered.

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