I have a Jacobs #18 super chuck with a MT#3 arbor for my lathe. Can I remove the arbor or is it made as one piece with the chuck. I don't see anything on the chuck saying it has a jt#3 taper. If it comes out, how do I go about it? I want to use it on the mill I just got.
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Drill chuck
- Thread starter mf294-4
- Start date
You could also put it on an arbor press, with a piece of steel round all the way down into the hole at the bottom, inside the chuck to pop the JT tapered end out of the chuck. Support the body of the chuck near the arbor coming out. You may have to rap the hell out of it with a hammer too. But as long as you support the body properly underneath, you are fine. Just don't support by the outer ring that spins! 
Bernie
Bernie
It's my understanding there is a dedicated tool, similar to a ball joint separator, for that purpose. It's worth mentioning though that taking a chuck on/off the JT side of the connection is usually avoided. Sooner or later, you'll bend or scratch something. Also, those types of tapers were meant to really take a set position and once they do, getting them apart is no picnic.
Ray
Ray
Gosh, I forgot Ray!
Like these! I even have some now!
http://www.zorotools.com/g/Wedge Sets/00055330/
They are good for other things too
Bernie
Like these! I even have some now!
http://www.zorotools.com/g/Wedge Sets/00055330/
They are good for other things too
Bernie
Those wedges work, but it can be positively amazing how much force it can take to get that taper loose. I've boogered more than one set of wedges and had to make some more to get the job done. My best results came when I inserted the wedges from both sides, balanced the rig resting one wedge on an anvil and smacked the other wedge with a small "single jack" sledge hammer.
:nono:
I wouldn't recommend this on a nice new super chuck. It shouldn't take a lot of force to break the seal between the tapers. Be gentle and go slow. The arbor press will work or you might be able to rig something up with a large vise if you don't have a press.
Just my two cents.
Steve
I have tried to do the same thing , and my experience was not good. Those arbours seem to be really in there tight.
From the few attempts I have made over the yrs, I would just pick up another chuck for the other machine. Pressing and whacking with a hammer cant do it any good.
I had one 3/4 chuck that was being stubborn, and I didn't want to hurt it removing the arbour. I ended up machining off the arbour up close to the back of the chuck. With a hole drilled into what was left , it was weakend enough to push it out with very little force.
For me, I think if you really don,t have to, then don,t do it. The out come could be a trashed chuck. That is just my opinion though.
From the few attempts I have made over the yrs, I would just pick up another chuck for the other machine. Pressing and whacking with a hammer cant do it any good.
I had one 3/4 chuck that was being stubborn, and I didn't want to hurt it removing the arbour. I ended up machining off the arbour up close to the back of the chuck. With a hole drilled into what was left , it was weakend enough to push it out with very little force.
For me, I think if you really don,t have to, then don,t do it. The out come could be a trashed chuck. That is just my opinion though.
I wouldn't make it my first attempt, as the arbor press should be first. Either way, the chuck needs to be supported well, like on steel round with correct diameter through holes for the exiting drill arbor. I keep pieces like this, of different diameters, by my arbor press.
If that doesn't work, and if you support the body of the chuck with the steel round, right around the arbor going in, and have the punch going right down to the top of the jacobs arbor, it shouldn't even bounce around. And the forces are all focused where they should be.
Bernie