Compound Dovetail Jig for Log Cabin Timbers

After retiring from the police department, my father-in-law finally had the time to work on his main retirement project… an Appalachian style log home, designed by both my mother and father in-law.

Like any log home, the main part is of course…the logs. The design called for 6×6 white pine timbers jointed with half dovetail compound joints.

Over the Christmas holiday my father-in-law and I built the jigs for cutting the dovetail joints.

Essentially the jig encases the end of the log that is being dovetailed and a chainsaw (with metal guides attached to the bar) slide down the jig and cut the dovetails. Because of the compound nature of the joints we needed to build a Left and Right version of the jig.

The jigs are made primarily out of birch plywood. Held together by glue, biscuits, and brad nails. To secure the log from moving within the jigs we used 3/8” threaded rod epoxied to circular knobs. Turning the knob pushes the threaded rod securely against the log, holding it in place. We reinforced the weaker parts of the jigs with 1/4” flat aluminum. To ensure that the chainsaw guide would slide smoothly on the jig we attached counter laminate at the guide contact points.

-- Matt, RI