Need help learning how to joint 39 inch long boards

A 39 inch board (assuming you only need edge jointing) is a piece of cake really. Tack or double-side tape a straight board to your stock (piece of plywood with a factory edge works well). Run that straight edge against your table saw fence, with the fence set so that the blade cuts a straight edge on the workpiece. Remove the straight-edge guide board, flip the workpiece, and rip a straight edge on the other side. If you have a good quality blade like a Forrest, you may be able to glue up as-is; If not, a few passes with your #7 (or #6 or even a jack plane will work fine on a 40" board) and it'll be ready to glue. Save the router for routing is my advice!
Now, if you don't have a table saw, you can still do it, use a straight edge guide with a circular saw to cut the straightest edge you can, then finish up with the hand plane.

Larry Wasserman Baltimore, Maryland
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