Building The Steven's Favorite

[TomG]

I needed a cutter to mill the 1.5" radius on the contours of the receiver. Since nothing like that is available commercially that I know of, I had to make it myself. I first modeled it up in SolidWorks to work out all of the clearances so I would have a better shot at getting them right the first time. I used a piece of 1" diameter O1 and turned one end down to .875 to match the largest collet on my mill. All of the milling was done in a dividing head, with a tailstock for support, using end mills and a boring head. The faces of the four flutes were milled first, then the blank was rotated 5 degrees for the primary clearance and the 1.5" radius was cut using the boring head. Next the blank was rotated 32 degrees and the secondary clearance was cut in the same fashion.

When the cutter was finished I tried it out on a piece of scrap aluminum and it seems to work pretty well. It hammers just a bit due to the lack of back rake but it should be fine for this one time use.