Morticing jig allignment

[Dave M]

I use a jig that looks like Martin's shown in his build thread. There is a difficulty lining it up, particularly as my side bending doesn't seem to go too well up at the head end!

So I mount the box in my guitar vice - yes it is skewed but that doesn't matter. I use a level to ensure the centreline is vertical.

Place the morticing jig over the box and use a small block with the centre marked to align the jig sideways with the centre line. Then use the level to make sure the platform is horizontal which means the router cutter should be properly lined up with the centre line.

Refinement is done by the fitting of the tenon as per the book.

The pics should make things clear. Sorry the images are in reverse order.

[kiwigeo]

Dave, I use a similar small block of wood with a centre line marked on it to check jig set up. I also run the router cutter around the cut with the router off and check alignment of the scribe it leaves in the wood. Once that's done the first cut barely skims the surface of the wood allowing me to again check everything is aligned