I'm about three quarters done with my rib mortices and I have to say it's a little hair raising. They aren't that accurate. My holes are a little outside the marks - side to side. I've planned to use epoxy on this boat all along. I will probably end up putting a dollup of epoxy in each mortice when installing the ribs. I'm thinking a little paste wax on each rib will stop them from being permanently glued into the mortices.

The picture is a drill guide that is supposed to give a uniform depth and hole spacing.

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