Have you ever painstakingly set a bit height, only to find that you needed to return to it later? Making individual gauge blocks for rail-and-stile, raised-panel, finger-joint, and profiling bits saves setup time. You can rout them from medium-density fiberboard or hardwood, but ultra-high molecular-weight (UHMW) polyethylene, shown left, makes a more stable block. (Assortment no. 143291, from Woodcraft, 800-225-1153 or stock planed to the same thickness as your project parts, cut blanks at least 4" wide and 6–8" long. Next, set up the bit in the router table and make test cuts in scrap to fine-tune the height. After routing project parts, rout the same profile on a gauge-block blank. Repeat for the mating bit, if needed. Then rip the gauge blocks to about 1 1/2" wide, and label them with the bit profile and stock thickness.To use the gauge blocks, chuck a bit into a table-mounted router and raise it to roughly the correct height. Place the gauge block with the mating profile beside the bit. Then raise or lower the bit until it slides into the routed profile on the block, as shown below left, and lock the height. You'll still need to test-cut scrap for a dead-on fit, but the gauge blocks will make that go a lot faster.