How to Cut Slot Mortise Joints in Wood Frames

There are a number of ways to join wood frames together—from dowels and metal fasteners to pocket screws and wood plates—but nothing is stronger than mortise and tenon joints. While mortises can be cut by hand using a chisel and mallet, the process is time consuming and not very accurate.

Enter the JessEm Zip Slot Mortise Mill from Woodcraft to take the drudgery and imprecision out of cutting mortise and tenon joints. The simple to use jig holds the stock firmly in place while a special bit cuts a slot in each frame member using an electric drill for power. The matching mortises in the rail and stile are then joined together with factory made tenons.

To use, simply clamp the jig to a workbench, set the adjustable stops on the jig to properly position, position the bit in the guide bushing, and drill into the wood using the attached lever to oscillate the bit back and forth. The result is a perfect slot every time that fits the premade tenons exactly.

Three sizes of bits and tenons are available allowing the JessEm to cut mortises of 1/4″, 3/8”, and 1/2″ widths. The jig even includes a shop vac attachment to keep dust to a minimum. Joining wood frames together has never been easier.

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How to Cut Slot Mortise Joints in Wood Frames