I bought Harbor Freight's four inch angle vise, which tilts forward 0 to 90 degrees on slightly incaccurate circular dovetails, thinking I'd make ways on the base and add it to me four inch cross vise and drill press mill. As it turns out, the base is wider than the jaws, so that wouldn't work and it was a bad idea anyway because it is work to add ways, preferably of cast iron, and a couple of holes for the lead screw mounting plate. So I set it aside.
On measuring the base, I found it to be close to five inches so I ordered their five inch cross vise, a heavy load up the steps at 30 pounds. I lost some muscle mass during a recent depression. It was hard.
I opened the box carefully and kept the Styrofoam blocking. I opened the jaws all the way and tried to drop in the angle vise. It wouldn't go. I removed the fixed jaw plate and the moveable jaw and tried again. It was close and it looked like a rectangular notch to clear the vise screw boss would do it.
Rather than hog it out, I jigsawed the notch. Now that was work! I had to keep the speed low enough for cast iron while providing more forward force than I'd ever used on the jigsaw. There's a simple roller behind to blade, just above the work. I sawed almost into each corner, and snapped the waste, leaving a coarse slot with mitered corners. It fit!
I wanted to make it look nice so I set it up on the existing four inch cross vise for milling. I tried clamping the jaw of the angle vise in the cross vise. No go. I tried clamping the jaw of the cross vise in the angle vise. No go. It must have taken me fifteen tries, frequently repositioning the cross vise from its central position to the limit to either side, before I risked damaging the ways and grabbed the circular way on one side in the angle vise, a milling setup level and solid enough not to need blocking and clamps.
After that I tried edge millling the slot with a 3/8 end mill but that was to far from square to work. That is, with the depth now controlled by pressure rather than a position setting, it was a self-guiding cut and produced irregular results.
I got out the dial indicator and moved to my final dimension off the part, then came down 0.020 inch from the surface. That's an 0.10 x 0.020 cut, and it was a piece of cake. Slowly I increased to 0.050 x 0.10, a healthy cut for a drill press mill. When each face had been milled, descending 0.020 to 0.050 per pass and with depths of corresponding cuts 0.100, 0.075, and 0.050, or something like that, the notch was square, centered, and radiussed. I finished it up with a little edge milling full depth to connect the straights and curves. I didn't use the feed screws.
Now that it is about right I'm going to find some thick black paint that matches the rest of the vise and it'll look like they were made together.
I can couple the parts by removing the rear jaw plate of the 5 inch cross vise and removing the main jaw, then retracting the vise screw, putting in the angle vise, and pressing on the angle vise, but that doesn't couple them. To couple them I'll locate four M6x1 holes in the cross vise, drilling the angle vise base to match, and clamp them together.
Then, with the tilting table on my new MT2 drill press to come, $99 from Harbor Freight, I'll have two axes of tilt, two linear feeds, and the down feed. A boring/flycutting attchment is available, and a reversing power tapper.
The ancient five speed, four inch machine will be offered here for $300 as the second of two self-reproducing milling machines I made in around 1995, and discussed here, then on ebay.
My physics project at NVCC: Google Groups, then "dgoncz" and some of: ultracapacitor bicycle fluorescent flywheel inverter