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Drilling hole in hard steel: Speeds? Feed? Lube?


Hot Rolled
Apr 4, 2017
Poway, CA (from Location field)
I was cross drilling a 13/64" hole in the 7/8" diameter Pin on the tow bar I use to flat tow the Bronco.
Anyway, I used poor technique, the hole got hot, I heard a SQUEEAK and the drill stopped drilling.
I have purchased a 13/64 solid carbide drill.
My questions are: What RPM should I spin the drill? Should I use oil or run it dry?
I have black cutting oil or tap magic that is like a light oil.
I just need to get through the final 1/4 of the way through the pin.

The hole location was not critical so I just center punched and drilled in the drill press. I really don't want to flip the part over and come in from the other side because the holes will never line up.
if you are drilling a 1/4 hole in "hard" steel , say 45rc ? with a "drillpress" i think you'd
be better off not wasting a fragile, expensive drill . those work great in a milling machine, but not good in a drillpress. a drill chuck is seldom capable of better than .003 TIR, and a carbide drill does not flex. . i'd suggest an m-42 cobalt screw machine drill @ 400 rpm , and stand on the feed , w/ cutting oil.