I built and then repeatedly tweaked a mortising jig. So far it’s working pretty well.
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The one snag was that sawdust would occasionally get wedged between the router plate and the frame of the jig, causing the router to bind and become difficult to slide. A little care to brush away the dust periodically took care of this.
I’m making 2 tables with 4 legs apiece. But, knowing that Murphy is never far from my shop, I made 10 legs. Good thing. On the very first one I cut a mortise all the way through that was supposed to go in only halfway.