While not a professional machinst, I've managed several shops over the years. I can't imagine taking 1/16" would take that long. Nor can I imagine it causing that much heat, especially if they use this stuff called coolant. I'd guess an hour tops for getting it setup and about 10-15 minutes to make one pass, and it might take 2-3 passes. Should be cool to the touch the whole time with coolant running. Even without it, it should be touchable when done.
'69 1/2T stepside, Sea Foam Green, 250 L6 w/ 3 on the tree, not an option on it, in the family since new.
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