If you've got different thicknesses of stock - ply or otherwise - the only way
to make good fitting dados is to cut them (or shim them to) slightly different
widths. Even if you have different thicknesses of ply, this little jig will
allow you to cut snug dados - of varying sizes, if necessary - very quickly. Try
doing that with a dado stack or special sized router bit...

I know it would be easier if ply was of consistent thickness, but sometimes it
just isn't. There can be thickness variations within a single sheet!
--
JeffB
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