I use a cross slide vise to center the hole exactly under the tap which is held in the chuck with moderate pressure- - - -I want the tap to be able to slip in the chuck jaws rather than break if it binds. Lower the tap to the hole with the drill press quill and hand turn the chuck to get the tap started. After it starts cutting, use a drill bit or a piece of round stock in the chuck key holes to turn the tap and chuck together. Once it's cutting well, loosen the chuck and use a regular tap wrench to complete the thread. Use plenty of cutting fluid. I use the same procedure to drill and tap very expensive rifle receivers for scope mounts.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!