Panels a bit too thick?

Seems like for 20” by 20” panels, 1/2” ply would be plenty for the panels. If the panels are set to the back of the rails so that molding can be placed around the edges, I’d leave at least 1/4” behind the grooves in the rails. Rubber “space balls” in the grooves should keep the panels centered and prevent rattling.

Hope this helps.

-- Rich, Seattle, WA

Most frame and panel doors and wainsote panels only use a groove about a 1/4” side. Half inch should be fine. Plywood doesn’t move around like solid wood does so you don’t need to be as careful with spacing and such. A little clearance and some foam weatherstrip bits in the grooves would probably be ok.

-- Michael Murphy, Woodland, CA.

I concur 1/2” should do the job

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Great! I guess I’ll probably go with 1/2” then… I’m always impressed by the willingness to help on this site… thanks everyone!!!

Keep in mind that the panel groove doesn’t have to be centered in the 1.5” rail. You can increase or decrease your exposure as needed, especially if you go with the 1/2” panels.

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