Convert a combination square to a depth gauge
Turn your combination square into an accurate depth gauge with two small pieces of wood, a thumbscrew, and a threaded insert. First, cut a 3⁄4 "-thick block of hardwood about 3" long, and cut a kerf down the middle just wide enough to fit over the edge of the blade on your square. Then, saw out the notch in the lower half of the block to fit around the head of the square.
Glue a piece of 1⁄8 "-thick hardwood to the bottom, as shown above. With epoxy, secure a threaded insert into the upper half of the block, put in a thumbscrew, and you're ready to quickly gauge the blade height.
—Mark Albrecht, Houston, Texas