How to Cut Double Tenons

Tenons and Tapering
Once the whale’s-tail profile is cut, finish the side pieces: cutting the tenons and tapering the sides.

Cut the tenons
Lay out the tenons using a marking gauge. Get the exact dimensions from the mortises in the top piece. Cut the tenons using a dado stack on the tablesaw. First cut the tenon cheeks.

Then lay out the tenon shoulders and cut them at the tablesaw. Finish the tenons using a shoulder plane and chisels.

The stretcher mortises
Also lay out the mortises for the stretcher tenons. Hog out the waste using a drill press, then square up the mortise using chisels.

Taper the sides
Once the joinery is cut, it’s time to taper the sides using two easy-to-make jigs. Make the jigs using a 3/4-in. plywood base. It should be a bit wider than the width of one of the side pieces. Loosely attach a fence at the bottom of one jig using a screw. Lay one sidepiece on the base, resting the “feet” against the fence.

Then, mark where the taper begins at the top of the workpiece using dimensions from the plans. Pivot the fence so the taper mark lines up with the edge of the jig. Then screw the fence in place. Attach a second fence to support the other side of the workpiece as shown in the video and trim the jig using the tablesaw.

Cut tapers on one side of each step-stool side piece with this jig. Then, make a second jig, using the same method, to taper the second sides of each piece.

Once the tapers and tenons are cut, it’s time to work on the stretcher. In the next episode, McKenna shows how to fit and join the stretcher. He also starts prepping for the wedges.

Video by: Gina Eide; Editing by: Michael Dobsevage