After I cut the opening for the wagon vise on the top of the bench, and spent the time to get the leg mortises sized correctly on the bottom of the bench, I debated whether to glue the legs, or pin the legs, or leave them as they are. In the fitting, I had to pound quite hard to get the legs to seat in the benchtop mortises. I figured it was going to be near-on impossible to pull it apart without rigging up a rope and pulley system of some sort. Still, I also know that working on this thing will involve lots of pounding, and Murphy being who he is, it will eventually start working loose. So I needed to reinforce the connection without having to pull it apart first. Pins it is.
I bought some 3/8" diameter oak dowels, drilled two holes in the front and back face of the bench where the leg sits in it's mortise, and then glued and drove home the dowels. The drilling was the tricky part here. I wanted the face of the hole to be clean, so I used a 3/8" forstner bit to start the holes, but I don't have a forstner bit long enough to go in deep enough to drill through to the other side of the leg's tenon. (I wanted to make sure the pin was seated in the benchtop wood on both sides of the leg.) So after starting the holes, I realized I needed a really long 3/8" drill bit. So off to Lowes I went. I bought several of those really long auger type bits commonly used in constuction.