Flexy Ply lamination - how many layers minimum?

[dkaardal]

I've got to make up a bunch of curved plywood panels for a crib project, and I've been dithering about the type of plywood to use. I'd originally planned to use 3 layers of 3mm plywood with 2 layers of 1.5mm maple veneer on the outside. This would give me a panel 12mm thick, which is about where I want it to be.

I've been doing some practice bends for other parts of the crib however, and I'm starting to get concerned about springback if I go with my original plan. I thought that I might want to try flexy ply, but I notice that the thinnest it comes in is 5mm.

If I still want to aim for around the 12mm mark for panel thickness, that would mean I could only use 2 layers of flexy ply, sandwiched between the 1.5mm maple veneer (13mm total)

Does anyone use flexy ply that could advise me on how stable/rigid a panel like that would be?

Radius will be around 15", with the panel being around 22" wide by 27" tall

 

[custard]

Hello Donovan, I've used flexi ply quite a few times, and I do a lot of vac bag curved lamination and constructional veneer cladding work.

I think I've seen a SU plan of your project, if I remember correctly the curved component is housed top and bottom in a solid component? Bottom line, it'll be more than adequately rigid.

Incidentally, 5mm flexi ply thickness is the nominal dimension, it often (but not always) comes in a bit less, plus you'll be sanding your 1.5mm Maple veneers so you'll lose a bit there as well, bottom line is you're likely to net out on or below your 12mm target, I wouldn't cut the housing groove until you're done, that way you can adjust the groove dimensions and the curve shape to accommodate the actual component rather than some notional, rod or plan based shape.

Good luck!

 

[dkaardal]

Excellent, thanks for the response! I'm glad to hear that it'll be stiff enough - I was not looking forward to having to buy a dozen sheets of 1.5mm plywood...

I'll order up a sheet or two and make a test panel - and I appreciate the tip on not cutting the groove until the panels are finished.

And if this was the SU model you saw before, then yep - that ones mine.