The Home Machinist!

This is a solid steel rod about 1 inch long and 3/4 inch diameter around the circle, about 1.5 inch overall across from the point. The black hole is drilled through the center of the circle.

I thought of starting with square bar a bit over one inch long and the same dimension as measured across from the extreme points (shown in diagram).

Cut the two parallel sides on the mill. Clamp the part end-to-end in the milling vice at the proper angle to cut the point.

Drill the hole (it's either 1/4 or 3/16) and use a screw to mount it standing up in the center of my rotary table, with the screw indexed to the center of the RT.

Then bring an end mill to the opposite end of the arc, across from the point, and rotate the part around each direction until it reaches the parallel sides. I'm not sure if the extra "fillet" left over from the radius of the end mill will matter at this point, but I suppose that I could remove most of that by cutting in a similar way that I did the point.

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Standards are so important that everyone must have their own...
Logan 10x24 Lathe, RF-30 Mill, 20 Ton Press
Disclaimer: I'm just a guy with a few machines...

Your way should work fine. Depending on use, I might make it in two parts and silver solder together. If it has to be one piece, I would start with the same stock as you, but longer. Drill the hole through and mount between centers on a dividing head. Use the extra length for driving/ mounting.

Wayne

You could finish up the fillet radius by using a corner rounding radius cutter. Mill the flat sections with a sharp cornered endmill up to the point of intersection between the radius and the flat. Then tilt the head of you mill (or rotate the part) and blend the sharp corner of the radius cutter to the previously milled flat sections with the existing radius that you milled with the rotary table.

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Bruce Mowbray
Springville & Southern RR
TMB Manufacturing & Locomotive Works