Morse taper drill recommendations

[Retromilling]

Interested to hear that a Jacobs taper will let go. May depend how it's fitted. Recently put one, 3MT, into a mount for a 80mm rock coring drill. Put the taper arbor in the freezer overnight and poured a jug of boiling water over the female arbor. Just bumped it in firmly and the guy is coring rock with it on a No 5MT radial drill. Will let you know if it ever slips, Combustor.

A 3 MT has way more area than a short jacobs taper so fitted the way you do it I can understand how much more grip it would have .
My chuck has only let go once when using a large drill and just getting it too hot and not peck drilling enough .
I don't want it so tight I can't get it off easy so I compromise .
If I fitted it with a press it would hold way better but I don't want to risk distorting the body of the expensive chuck .
I only use large drills infrequently .

[Combustor]

Had a job for the 1" drill in my $50 Ozmestore drill set today. Had to bore thru the length of 4 pcs of steel each 4.5" long, steel was old excavator bucket pins, so a bit better than mild steel. Gave the cutting edges a light touch with a diamond stick before starting, as the original grind was a little rough, but angles were correct. Ran a 3/8" pilot hole thru the pieces before sinking the 1" bit in firmly, in a heavy lathe round 300 rpm. Used a bit of oil down the pilot hole to help chip flow, cutting quite cleanly. Bored all 4 pieces, total of 18" cut and drill edge was not visibly dulled. For my application and at $50 for the set I find that quite acceptable. No way to know if this is typical of the product or maybe I was lucky, so not complaining. Combustor.