View Full Version : drill chuck and arbor question
12-06-2005, 10:42 PM
I just got a new jacobs drill chuck with #3jacobs taper hole, also a new arbor with the 3jacobs taper and 3 morse taper to go into my tailstock on my lathe. I am wondering if I need to lightly press the arbor to the drill chuck before using or will it seat all right by just installing by hand. I just dont want it to start spinning on me the first time I use it. Also is there an easy way to get them back apart once they have been together for a long time. thanks in advance from a newby
12-06-2005, 10:57 PM
the jacobs taper is self holding, if all is well (no dirt, bumps or bruises) a couple of good taps (say on a wood bench or with a soft dead blow hammer) will seat it for life
12-06-2005, 11:52 PM
A tap or two with the jaws all the way IN that is.
Chuck removal is done two ways: 1) use the tapered wedges Jacobs and a few others sell. The wedges are put between the bottom of the chuck and the end of the taper mount where there is 'usually' a space. By putting the wedges in opposite each other and closing the jaws of a vise on the wedge ends the chuck will be popped off. If the space is too narrow... Wedges come in several different sizes and are U shaped with thin end about 1/16th and thick closer to 1/8" thick.
2) If the chuck has a through hole and is open through the bottom when the jaws are retracted you can use a soft punch to knock the MT adaptor off the end. Some have suggested drilling out the chucks to make such a hole before installing. The swarf might be hazardous to the innards. Some chucks are open and some are not.
3)Finally you can try inertia. If you hit the small end of the MT taper hard enough the chuck might fly off to parts uncertain.
When installing an arbor in a new chuck, retract the jaws completely, clean both mating surfaces with some alcohol, and then put the chuck in a 400'F oven for about one hour. Once the chuck is heated through, remove it from the oven, and set it on a block of wood, jaw end down. Set the arbor in the mating hole, and give a sharp whack with a rubber mallet. Let everything cool, and it will NOT come apart.