08-20-2012, 06:55 PM
You may need to finish the "corners" of the milled shape by hand with a file. The bigger the end mill you use, the more finishing you may need to do.
The original was either as-cast or broached. If you can make one out of bronze, brass or aluminum, it would be a piece of cake to make a HSS broach.
Another method, if you can use a soft steel, would be to make a shaped mandrel, then a thick-walled blank of the part. Slip the blank over the shaped mandrel and pound the blank bushing down around it until the shape is completely forged. Use center hole in the mandrel to finish turn the O.D.'s, press it out when done. That would give you the ultimate strength part.
The original was either as-cast or broached. If you can make one out of bronze, brass or aluminum, it would be a piece of cake to make a HSS broach.
Another method, if you can use a soft steel, would be to make a shaped mandrel, then a thick-walled blank of the part. Slip the blank over the shaped mandrel and pound the blank bushing down around it until the shape is completely forged. Use center hole in the mandrel to finish turn the O.D.'s, press it out when done. That would give you the ultimate strength part.