Those who have been frustrated by setting up a lock miter bit accurately, and with the often tedious “test cut and readjust” process that follows, will appreciate this new two-piece Lock Miter Master Jig Set from Infinity Cutting Tools. Made of anodized billet aluminum, and CNC machined for accuracy, these little jigs take the mathematics and trial-and-error out of the setup equation. Each jig (the smaller jig sets up lock miter bits that cut 3/8- to 3/4-in. joints; the larger jig adjusts bigger bits that cut 5/8- to 1-1/8-in. joints) is milled with a profile that registers it positively against one of the bit’s cutters. Rare earth magnets hold it in place. White registration marks on the jig are used to establish bit height and distance from the router table fence, when checked against a layout mark on each pair of workpieces to be joined.
Smaller secondary reference marks enable the jigs to set up joints on workpieces of unequal thicknesses as well as when the lock miter pattern should be offset rather than centered on the joint. Infinity’s Lock Miter Master Jigs will work with most brands of lock miter bits. Downloadable PDF instructions and a promotional video showing proper jig setup can be found on Infinity’s website. The two-piece Lock Miter Master Jig Set (item 00-LMM) is available now and sells for $49.90. Note: a lock miter router bit is not included.