Once all the pins are bored, you’ve got a bunch of waste around the pins that you need to clear away. One way to make quick work of that is to make a pass on the table saw with the blade height set very low. That will clear away most of the waste. I didn’t do that—I did it the hard way with a knife and chisel. i did this because I chose to use some nice clear pine I had for the end pieces but I was afraid I’d have some nasty chipout if I used the table saw. Instead I ended up with a lot of crushed grain trying to cut & chisel it out. Que sera sera…
Anyway, I used a marking gauge to set a cut line around the waste area.
Next, the fishtails need to be drilled into the side pieces. For this I flipped the old Shopsmith up into the tradition vertical drill press orientation. I setup the fence with a sacrificial fence attached to it. There’s a stop block nailed to this fence. This will allow me to use the same spacer blocks to make the holes as I used to make the pins. With the 1/2” forstner bit in place, I set it to cut offset 1/16” into the fence—just like the pins are offset. (You may want to tweak this by a hair less than 1/16” so that you have some excess. Better too much than too little…) As always, use a scrap block under the piece you are drilling.
Just like with the pins, I work from right to left, boring the holes using the spacer blocks. Three fishtails on one end, two offset on the other end.
If you’ve kept everything meticulously aligned, you should be able to dry fit your pieces together. It should be a very snug fit.
I also milled a 3/16” slot on the inside of all 4 pieces to hold the bottom piece. I stopped this slot in the front of the side pieces so it wouldn’t show where the joint comes together. I also milled a 1/4” slot stopped in the rear in the side pieces for the sliding top. These were cut with a slot cutter using the trusty old Shopsmith, but they could certainly be cut with a router or router table.
Cut a bottom piece to fit in the slots. Now you can dry fit the whole box and start cleaning up any protruding joint pieces. You can see my pins are a good 1/16” proud. I went a little overboard since my last box had the opposite problem.
Last thing I did was cut the top and cut the dadoes for it to ride in the slots. I also cut a decorative pull as part of the lid. And there you go, a Fishtail box.