Pattern-Rout the Edge: Next, I cut out the return with a jigsaw, cutting to the outside of the routed 1/8-inch-wide channel.
Pattern-Rout the Edge: At this point I go ahead and cut out the outside edge of the return, carefully following the line with the jigsaw, then fine-tuning the edge with a belt sander.
Pattern-Rout the Edge: I want this edge to be as smooth, flat, and perpendicular as possible, since it will guide the 1/2-inch-radius round over bit I use to bullnose the edge of the return. For now I set the return aside to work on the tread.
Repeat for Treads: I follow the same sequence for the tread as for the return, first routing a groove with the 1/8-inch bit.
Repeat for Treads: Testing the fit: Though made with a single template, the joint is better than that on some of the factory treads I’ve seen. Some minor sanding is all it needs.