Wedge is the secret to perfect angled mortise-and-tenon joints
I don’t travel with my tools very often (three or four times a year), but it doesn’t matter. Packing up your tools so that they don’t get damaged en route is a pain. In the past, I would wrap up my planes in towels, sheets of packing foam, whatever. Then I’d put them in a cavernous, plastic tool box. Chisels and layout tools went in there, too. It was a jumbled mess. And once I got to my destination, it was still a pain, because tools where hard to find, keep track of, and I was always worried that when I packed up everything for the trip home, I’d leave some beloved tool behind.
So, I knew I needed a travelling tool case that keep them safe and orderly. This is my solution. It’s three parts: the legs, the big box (a plane till), and the small box (there are drawers in there for chisels, layout tools, etc.). I’ll write another blog when I’ve completed everything, but I wanted to share the technique I used to make the mortise-and-tenon joinery for the base. In particular, how I cut the angled mortises and the angled shoulders on the tenons. The trick was a wedge that I used to set up my miter gauge, and to angle the legs when I mortised them with a hollow chisel mortiser. Because I used the same wedge for both, the tenon shoulders were a perfect match for the angled mortise. The photos above show how I did it, step by step.
Travelling man. This is the tool cabinet that I'm making to carry and store my tools when I travel to teach and demonstrate. It breaks down into three pieces.
Step 1: Make a wedge. The slope needs to match the back legs' angle. And make sure that the straight edge and end are square to one another.
Step 2: Set up the miter gauge. The sloped side of the wedge goes against the miter gauge, and the end of the wedge is flush to the saw plate.
Step 3: Cross cut the legs and stretchers. They all get cut at the same angle. The top and bottom ends of the legs are parallel to one another.
Step 4: Mortise the legs. Clamp the wedge to the fence, and slide the leg down the mortise. This accomplishes two things. First, you can use the machine's depth stop for each cut, ensuring that the mortise is the correct depth across it's width, which wouldn't happen if you moved the wedge, too. Second, by sliding the leg down the wedge, there is always material for the top side of the bit to grab.
Flip the wedge and leg to center the mortise. If you only flip the leg, then the chisel will mortise at the wrong angle. (This is optional, but I like a centered mortise, because it makes it easier to cut the tenon.)
Step 5: Cut the tenon cheeks. A dado set makes quick work of them. The angled end grain should be flush against the rip fence when you cut the shoulder.
Step 6a: Cut the edge cheeks at the bandsaw. This cut is parallel to stretcher's edges, so there is no special set up needed.
Step 6b: Cut the top and bottom shoulders. These are parallel to the end grain, so register the stretcher's end flush to the fence and carefully guide it through the blade. Leave a bit of waste and then pare it flush to the other shoulders.
Ready for assembly. The wedge took all of the guess work out cutting the joint, and you can easily get a fit joint straight from the machines.
No gaps. This is what it's all about. The joint comes together tight and strong.
Angled legs. The back legs come out on a slant to provide more stability. The base is joined with mortise-and-tenon joinery, which means that either the back leg mortises or the tenons going into them must be angled. I chose to angle the mortises.