RE: Building The Steven's Favorite I had to go back to work today to support my expensive hobbies so I only managed to get a couple of hours in on the Stevens.
I had an old piece of jig and fixture plate laying around so I decided to use it to make a sub-plate to hold the receiver. A sub-plate makes it much easier to work on a complex part because there are no clamps to work around. In addition, it allowed me to spot holes at the center of all the radii making changes in set-up much quicker. After making the sub-plate I had time to saw out the rest of the receiver and make one cut on the top, a 3" radius blended into a 16º angled straight cut. It's been a while since I've used the rotary table and it was fun to dust it off for a change.
Tomorrow I'll harden the form tool so I can use it on these surfaces before breaking the set-up.
Tonight wasn't as productive as I'd hoped. I hardened the cutter and it came out glass hard with no cracks but I think I got carried away tempering and went too far. When I tried it out on the receiver, it wouldn't hold an edge. I'll need to heat treat it again before moving on to the next step. I'll leave it full hard next time and just be careful not to push it too hard and chip it. At least the receiver is starting to take shape.
The second time worked like a charm. I re-heat treated the cutter and left it full hard. That would not have been an option if it was smaller because it likely would have broken during use. Then I sharpened the face of the cutting edge with a die grinder and went to work. The cutter had to be fed very slowly because of the amount of cutting edge in contact with the work, but it cut cleanly and held an edge. The next task is to mill out the tangs where the stock attaches and then finish hollowing out the inside.
I had to do some house painting today so it cut into my shop time a bit, but I still managed to get the upper and lower tangs roughed out. With all of the material that needed to be removed, I broke out a 3/4" roughing end mill to speed up the task. I forgot how much fun they can be. At one point I was taking a 5/8" deep cut at a 3/4" per minute feed rate. The next task is to finish mill the inside of the tangs, round the ends and drill the holes in them.
Lots of clamps are mandatory when cutting steel and a piece of paper between the part and the table will help keep it from moving.
Notice the clamp and spacer to support the long flimsy tang.
A 3/4" roughing mill, 5/8" deep, 3/4" per minute, no coolant. I love these cutters!
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