I want to make a bunch of identical molds, for 3/4" diameter model
airplane wheels.

I'm envisioning a tool that's 3/8" across, that I just sharpen up, grit
my teeth, and push into a spinning piece of aluminum to make my desired
profile.

Is this a sensible thing to consider? Is there some other way (short of
CNC machining) to easily duplicate cavities in the ends of a bunch of
aluminum tubes?

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