Profile trim screw length going into plywood walls?

[2bits]

I am about to install my roof Aluminum and I found a box of 1 5/8 stainless steel screws and I was wondering if this might be too long. My worry is because I will be screwing into the endgrain of plywood which isn't exactly the most stable. Any suggestions on screw length given the material I will be going on? I will be going through the Aluminum trim, the .040 aluminum roof, 1/8" Epoxy hardended masonite, and then the Plywood.

Thanks!

[toypusher]

I would thing that 1/2" to 3/4" would do. There should not be a need to go into the plywood, the 1/8" Epoxy hardended masonite should hold very well. You may want to predrill to prevent any cracking of the epoxy. Hope I understand that the aluminum is over the masonite and that is over the edge of the plywood.

[2bits]

Yup you got the layout correct, thanks for the reply!

[madjack]

Thomas, I used pan head #8x1" SS screws for the same job...mainly because I had them...I predrilled the holes and putt-a-dab of sealant in all the holes as I fastened the screws.........
madjack

[2bits]

Thanks a bunch Madjack! !!