I need to drill some 21/32 holes with a hand drill, not accessible to
drill press.

I do not have a reduced shank 21/32 drill bit and new they cost $30+.
I have a 21/32 straight shank drill bit, but it is too wide to fit any
of my handheld electric drills, which go up to 1/2".

I thought I could reduce a shank of that drill bit by simply chucking
it in a lathe and taking off some diameter with a carbide tool. What
are the drawbacks, if any, of doing so?

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