Woodworking Tips Index

Squaring Gauge It’s easy to check whether a drawer or cabinet is square. Simply compare the length of the two diagonals. But once the clamps are in place, it can be difficult getting the end of a tape measure over the corners of the project. And placing the tape measure inside the corners makes it hard to get an accurate reading. That's when I use the adjustable squaring gauge shown in the photo at right.

The gauge consists of upper and lower extension strips that are held together with a sliding dovetail joint, as you can see in the drawing. (I used a 14° dovetail bit to rout the groove and then used the same bit to sneak up on the size of the matching tongue.) By sliding the pieces together, you can adjust the length of the gauge. Note: An L-shaped hook in the end of each piece allows the gauge to fit into the corner of a project.

CAM - Once the gauge is adjusted for the first diagonal, tightening a small cam “saves” the setting so you can check the second diagonal. The cam is an irregular-shaped piece of hardwood (see pattern) that fits in a slot in the upper extension. After attaching it with a machine screw and lock nut, raise the cam when you need to lock the gauge in place.