If you don’t have commercial miter clamps, here’s an effective way to glue up a mitered frame without them. First, dry-fit the pieces to ensure that the frame is square and the miters are tight. Then make two squarely crosscut boards a few inches wide, and as long as the shortest inside dimension of the frame. Tightly clamp these “pinch boards” between the long frame members, offsetting them from the ends to allow for glue squeeze-out. Double-check the joint fit, making adjustments if necessary, then apply glue to the joints, and clamp the miters together as shown. Note that for frames with an inside rabbet, you’ll need to temporarily fill in the rabbets on the long members to prevent the pieces from cocking under clamp pressure.
—Rick Melpignano, Enfield, Connecticut
