Tapered is the normal way for a chuck to be installed, even on substantial
sized industrial drill presses and it works fine if it's seated correctly.
I would guess you had a burr or ding or didn't properly clean the one you
couldn't get to seat and stay. The tapered seat IS the better way.

--

Mike S.

wrote in message
...

I had the same thing happen. I never was able to get it to stay on.
I considered using JB Weld, but I just bought another drill press at
an auction and scrapped the old one, cuz I got tired of fighting with
it. You'd think they would have a keyed shaft or some other BETTER
method of putting the chucks on.