As I was demo'ing the old drawers from my kitchen, I found this sticker on the bottom of one of them:
The plywood is a true 1/4" and made of hardwoods. I did a Google search on Weldwood Plywood and found this brochure from 1944:
That's a blast from beyond my past!
I've already started to recycle the panels. Since I've got a bunch of groov es to cut in 3/4" stock for my kitchen doors, I made a zero clearance inser t for my table saw. The extra blank in the photo will be used to make an in sert for my dado blade.
The original metal insert uses a screw at the front and a "spring tab" at t he rear to hold it secure to the table. I chose to drill and tap the rear l edge that the insert sits on and use screws to secure both the front and re ar of the plywood insert(s). My table saw has a 3/8" ledge all around the i nsert opening so I don't expect any sag in the insert. If I notice any, I'l l laminate another piece onto the bottom of it to stiffen it up.