Jacobs Chuck, #1 Morse Taper

[Frank Hagan]

Woe is me! :(

My Jacobs chuck arbor has broken off in my drill press. Can you buy the arbors separately? How do you separate it from the chuck? Or do you buy a complete assembly ... and where?

http://users2.ev1.net/~fshagan/chuckbroke.jpg

Info on the arbor itself:

JACOBS CHUCK ARBOR
NO. 1 MORSE TAPER FOR MODELS
6A - 12 - 34 - 500

[Jim Dunn]

You can by the arbor separately. Or you could have the tang welded back on. We used to have that done all the time in the machine shops I've worked in. The chuck has what is called a Jacobs taper on the end where it goes into the chuck. It can be a lot of trouble to remove it.

[Randy Meijer]

You can get replacement arbors from www.grizzly.com (http://www.grizzly.com) . As for removing the old one, open the jaws of the Jacobs chuck. You may see a hole in the bottom of the chuck...if so you should be able to drive the taper out. End of the arbor may be drilled and tapped with a machine screw holding it into the chuck which would need to be removed first.

There are several different sizes of Jacobs tapers. Many times the size of the Jacobs taper is stamped on the chuck.

[Frank Hagan]

Now I'm wondering if I even need to replace it ... it is still poking up a bit through the slot where you drive a wedge (?) in to force it out. Maybe I'll just push it back up into there ...

I noticed it chipped when I started to take it out to clean up the chuck. I had that sinking feeling you get when you break something you like very much, but if I can still remove it and reinsert it, and its tight in the taper, that should be OK, right?

[Jim Dunn]

If you only remove it "ocassionaly" I wouldn't mess with it. And my comment about welding it, I should have said braze it. You don't want to get it to hot? Not sure about that last statement but as I remember it now it was brazed. Try to buy a "drift" which is specifically designed to remove morse tapers.

[Frank Hagan]

Thanks, guys ... it looks like it works fine even with the tip broken off the arbor. There's still about 3/8" of it sticking up where a drift would push it out. I'll get a set of drifts and use them next time.

[Greg Mann]

Frank,

You might be able to get away without the tang if your machine is low horsepower, but, something caused the tang to break in the first place. If it twisted off due to torque, you need to be aware it could happen again. Only the next time you could score the bore in your machine. Tapers of that size are not very expensive, and, if Randy is right about your chuck, it is an easy fix. The tang is primarily for ease of removal but also serves as a safeguard against spinning on the taper. In other words, it's there for a reason, I would recommend replacement.

Greg

[Frank Hagan]

You raise some valid points, Greg. The press is a 1/2 hp, and run for woodworking only, so it probably qualified as a low stress application. The tang tip broke off when I removed the chuck ... didn't have the proper drifts to drive it out, so my clumsy efforts chipped off the end of it.

I'll need to get a proper set of drifts and probably replace it ... if I can figure out which Jacobs taper is on the end of the arbor that fits into the No. 34 chuck, then I'll spring for the $4 to $5 these things cost! I was surprised to find them that cheap ... seems like nothing I do costs under $20!

[Randy Meijer]

Easiest thing to do if you have a "brand" drill press would be to contact the manufacturer. They should be able to tell you what taper is required for your chuck. Failing that plug the terms "JACOBS TAPER" into a search engine like Google and it will return some sites, at least one of which will show the specs for the various Jacobs tapers. I have seen several but it was a while ago and I didn't bookmark any of the sites.

[Jim Dunn]

Enco.com (No affiliation) should be able to provide you with the necessary parts, or a whole new chuck already with the #1 tang.

[Dennis Peacock]

Enco.com (No affiliation) should be able to provide you with the necessary parts, or a whole new chuck already with the #1 tang.

Agree.!!!!! I have gotten even the hardest to find Jacob's Taper configurations from Enco. The service if very good and the products are top notch in my book.