I’m taking a tea break, I’m English and that’s how we roll, so I thought I’d put some more detail into the previous post about cutting the mortises in my (bench) legs just in case someone else wants to try this. I won’t go into the enclosed mortise; the routing process is identical, but one only needs to square off the corners.
Remember from my previous post, I’m using a 1/2” router bit and a 3/4” collar so I have a 1/8” space between the jig and the actual cut. I start by striking a line, across my piece, 1/8” longer than I want my finished mortise length and then I place the inner short piece of one half the jig on the line and clamp:
Here’s my clamping setup.
Each clamp has a purpose. The furthest handscrew clamps the workpiece to my table top and also stops the piece rotating on the middle handscrew. The closest handscrew clamps one end of the jig to the work piece and the work piece to the table. The Bessey rapid action clamp pins the jig fences to the work piece and the quikclamp aligns the two halves of the jig so the router doesn’t get hung up.
Once I’m happy with the setup, I root it out. Because of the thickness of my material I routed in 5 passes using the step depth thingy on my router to cut 1/4” deeper each pass. I end up with this:
Now I have to chop/saw out the remaining waste. I start by squaring the corners and then align the back of my chisel with the end of the mortise and give her a whack. This cuts down into the waste.
I then run my chisel at an angle, bevel down, about 1/8” back from the face and cut out a piece:
This sort of splits or shears out a triangular piece to the depth of my initial cut. I clear out the waste, chop down the face again, run my chisel in at an angle about 1/8” back from the first and cut out another slice. I repeat this until I feel like I’m half way down:
Repeat the whole process on the other side until I break through.
I saw down the inside faces staying away from them:
And the main chunk of waste will drop out. I use a wide chisel and reference the back against the machined surface of the face and slide the chisel sideways making a shear cut. I sneak up on it and keep at it until the inside faces are flat.
And this is the final product: