In Sept 2011 I made a post on shaping the groove in the bottom of a reel foot. Part of the problem was that the groove radius needed to be about 0.35 inch, and the largest ball end mill that I could install on my Sherline mill was 0.375 inch (0.188 radius). So the answer was to “generate” the required radius by multiple passes of a smaller end mill: a certain depth at 0.125 off center, a little more depth at 0.100 off center, etc.
But now I have an “X2” size mill from Little Machine Shop, and it has an R8 collet system. R8 collets can be as large as 3/4 inch. So here is an 11/16 ball end mill and the groove (0.344 radius) it makes for the sole of the foot.
It took a lot of time to sand out the axial ridges on the generated arc. Now that is all behind me.
My advice to the aspiring reelmaker: You need both a lathe and a mill. These are very different tools. The Sherline mill, despite being one of the few American made tools you can buy, is too small for work on reels (even though I made more than 40 reels with mine). Milling requires a heavy and rigid tool, and a mill should be made from cast iron instead of aluminum.
The lathe is a different consideration. I am keeping my Sherline lathe because it allows me to work on parts up to 3 inch diameter. See the recent post on custom chuck jaws.
I turn reel parts with 4 types of work holder: 3 jaw chuck, 4 jaw (independent) chuck, faceplate, and ER-16 collet. The Sherline lathe lets me change these by just screwing on to the 3/4-16 spindle nose thread. The Chinese origin lathes from Little Machine Shop, Micromark, and others have a flange on the spindle. Work holders mount by studs and nuts, a time consuming installation.
Yes, I do wish that my Sherline lathe had more torque at low speed. The lathe stalls when I try to ream the female slide of a rod ferrule set. This might be cured by using a brushless motor drive.