On 5/23/08 7:36 PMMay 23, "Tom Watson" wrote:

On Fri, 23 May 2008 16:35:46 -0600, "asmurff"
wrote:

I'm going to cut a dado in 2 pieces of plywood to put a third piece of
plywood into on the tool stand I'm building. Is 1/32" wider than the plywood
thickness enough.

What I have come to do is to not use dadoes that are the full
thickness of the ply. I usually make a dado that is in width from a
third to a half of the nominal thickness of the ply. Then I cut a
tongue in the other piece to match that width.

Tom,

The photos that you posted in a.b.p.w illustrate this very well. You have
added a technique to my bag of tricks. I can see how this can be used to
advantage.

I would have thought that the tongue would be thicker - 1/2 to 2/3 the width
of the shelving.

The offset tongue should be made on the bottom face of the shelf so
that the laminations of the shelf ply are loaded in compression,
rather than being under tension.

That makes sense. Thanks for the rationale behind that part of the
technique.