According to Norm Dresner :
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That I find amazing. What brand of 1/2" drill chuck is it which closes down to grip a #75 drill bit?.
Can you check whether it will grip a #80?
If it does not, you can go for the sensitive adaptor (either the one in the eBay auction to which I pointed, or another similar one) which will also give you more control and feel in feeding the drill bit.
I've done down to #70 in the tailstock of my small lathe -- an Emco-Maier Compact-5/CNC, with a 0-1/8th Albrecht chuck on a #1 MT arbor. And that worked well enough in 12L14 steel -- but I kept worrying about the lack of feel that the leadscrew gave me with that tiny a drill bit, so I was *very* careful.
Good Luck, DoN.