Gluing blocks into the corners of butt joints provides good reinforcement. But the technique caused me untold headaches trying to keep things aligned and tight until the glue dried. Then, I figured out this no-fuss way shown at top to clamp the glue blocks in place.
First, I cut two equally sized scrapwood glue blocks. Next, I cut the right-angle clamp block so the length of the face opposite the 90° angle roughly matches the combined width of the joint and glue blocks. A strip of double-faced tape keeps the clamp block positioned while I install the glue blocks and tighten the clamps.
--Roy Kirkpatrick, Sacramento, Calif.