I think I understand how it works. The router table slides in the wood at the sides, which also provides support for the mechanism with the large screw. This provides your z motion. Is this correct?
Seems like a sheet of 3/4 inch plywood would work as well as the metal router table - just mount the router directly to the plywood.
A slot mortiser is so nice for making mortises. I used a professional model at school and have been wanting to make one for my home shop for a while now. Once you use a slot mortiser you'll never go back to jigs and a router for mortises.
Thanks for posting.
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