Dumb newb ??'s RE: changing drill press chuck

[Teutonic]

Apologies in advance for a total novice question. About a year ago I bought a craftsman 12" drill press, model 21914 (AKA 315.214140). It was a floor model (perhaps a return- missing the chuck key, safety button, and several other things) but it was $129 and I got all the missing parts free after making a warranty claim. I do not, however, have the manual and Sears' website doesn't recognize the model # anymore . So- I need to chuck up a bunch of valves and polish the stems, but the runout in the chuck is ridiculous. I think the spindle is ok (haven't put a dial gauge on it) but you can see the runout in the chuck. So- the original chuck says JT33 - 1/2" on it (see pic 1). I am thinking A) unmounting the chuck and remounting, or B- paperweighting this chuck and buying a Jacobs or something better.

The dumb questions:

1- I presume that the chuck is a friction mount and the JT33 refers to the taper on the spindle, so any chuck with these specs should fit?

2- How to unmount this chuck? I have been looking through the Enco catalog and see wedges and drifts. Do I need the mini-pickle fork wedges that push the chuck off the spindle, or a drill drift? Based on the slot in the spindle (pic #2) I would guess the latter. Can anyone eyeball what size would work for this spindle?

3- I recall reading a review of this drill press that it had an MT2 arbor in it. I assume that means that the upper taper on the arbor is MT2 and the chuck mounting taper is JT33?

Pics for reference:

 

[nissan_crawler]

wedge a tapered piece in the spindle, and tap it in. THat will knock out the arbor and the chuck. Then I just open the jaws of the vise and set the chuck on top of it arbor down, and tap through the chuck with a punch, doesn't take much. It's the easiest way I've found. You don't need any fancy schmancy tools, a regular punch and any old piece of tapered steel will work, if the others are missing.

 

[Merkava_4]

If you open up the chuck all the way, can you see a screw down inside there? Or maybe I should say up inside there....

 

[Teutonic]

Thanks for the input! No screw up in the base of the chuck. Just a little dimple in the middle which I guess would be the center of the arbor when it was mfd.

 

[goodfellow]

That's a friction fit. Get a wedge and put it in that slot on the spindle column and tap it in slightly with a hammer. The JT33 chuck should just fall out

 

[Teutonic]

I am tempted by this Rohm chuck (http://www.use-enco.com/CGI/INSRIT?...MKANO=205&PMKBNO=1880&PMPAGE=51&PARTPG=INLMPI) but the specs say J33 mount. In Enco's dropdown menu for chuck mounts they do differentiate between J33 and 33JT. [Newb mode]Is there a difference between these two?[/newb mode]

Perhaps this is a better choice? (other than the backorder status...)

http://www.use-enco.com/CGI/INSRIT?PMAKA=319-3119&PMPXNO=19506524&PARTPG=INLMK32

I know, $100 chuck on a $130 drill press. Retarded. But you should see how bad the factory one is....

 

[goodfellow]

Before spending $$ on a new chuck, you'd be well served to get the old one out and thoroughly inspect that spindle. Cheap drill press = Cheap Spindle. Make sure the taper inside isn't deformed in any way.

EDIT -- you're correct in your original assumption JT33 refers to the chuck and MT2 refers to the arbor

 

[MXtras]

I do not believe there is a difference between a J33 and a 33JT. They are both Jacobs tapers - I think it's basically them that do not know they are the same.

I did not look at the links, but Rohm is a premium chuck, by the way. Excellent stuff.

Here's a helpful place for arbors, by the way:
http://www.victornet.com/cgi-bin/vi...tments=Drill+Chuck+Arbors:263,273,275,728,309

Scott

 

[rsanter]

you really do not know that it is the chuck, it could also be the arbor it is on.
the arbors are cheap so you might want to try that first.

do you have a friend that has a drill press, lathe, or mill that runs true? if so you could check it with that. if you do not I would be happy to check it for you but it will cost you the shipping back and forth

bob

 

[Teutonic]

Thanks for all the great info (and the kind offer, Bob), I appreciate it. For now I will pull the chuck and check the taper. I have a dial gauge and can measure the runout on the spindle, arbor and chuck to see why the chuck is wobbly. Will report back when I get a chance to play with it.

 

[W-Cummins]

The correct way to remove the chuck from the morris to Jacobs taper arbor is with CORRECT Jacobs chuck wedge set ( Enco sells them for a few $) You might find some cheap piece of **** chuck that you can hit the end of the J taper through the chuck, but all of mine aren't made that way. BTW you can get a nice Rohm keyless chuck off e-bay new cheaper than Enco sells them for. I have 3 of them, and although they are not the best, they are nice quality chucks.

William...

 

[MXtras]

In addition to using the correct wedges as mentioned by W-Cummins, I might add that it is imperative that you do not use a hammer unless the chuck is on a removable arbor. If the quill of the DP has the taper then use the wedge set and a C-clamp to press the wedges together - not a hammer. This will prevent damage to the bearings. It's a 1.5 person job.

Scott

 

[Teutonic]

Followup:

So the stock arbor for a 91214 is removable, I used a #2 drill drift and it popped out easily. Getting the chuck off the arbor was a bear- had to use a gear puller. I pressed the Rohm chuck on the arbor with a bigger puller and then tapped the arbor back into place.

RESULT: Huge improvement- the chuck turns much more evenly, at least by eye. Enough to polish my valves. Thanks for everyone's help!

 

[MXtras]

FWIW - put a few coats of automotive wax on that column every once in a while. It will drastically slow down the surface rust.

Scott

 

[Charles (in GA)]

After much trying I was never successful in getting my Jacobs 3/4 chuck (18N) off its arbor and finally gave it to the machine shop at work. I got it back a couple of hours later, reseated on the arbor, running much truer than before. I think they ended up dipping the arbor in liquid nitrogen to shrink it so it would break free of the chuck.

Charles