"Tapered" Jacobs chuck!!!

[Alan R]

OK Guys, getting a bit frustrated now. Just got a used Rockwell radial drill press (11-280) at an estate sale that had a lot more problems than I expected. The latest... followed some good advice from you folks as to how to remove the old chuck (worked like a charm). Unfortunately, I was expecting to see threads when it came off, but no, there was only a smooth tapered shaft!

This chuck ("Jacobs - Multicraft" - some #'s on lower end if helpful) is obviously "pressed" on? Seated back on without any problems, and I would use it, but it is a bit beat and has no key. Any idea as to what replaces this? Would seem to need a different spindle shaft (if that's the correct term) with a threaded end unless these "threadless" chucks are still out there. Not having any luck finding them.

Anyone know what I have and how to upgrade?

Thanks!

 

[metaleltr]

Look at the chuck closer should specify the taper. The female taper in the chuck and it's corresponding shaft are a Jacob's taper you should see ST followed by one or two number. You need to find a chuck with the same taper, they are common in precision machining and drill presses.

 

[Steevo]

Enco, and many other online machine tool sellers have a wide variety of chucks that come with tapered shafts.

 

[A_Pmech]

It sounds like your spinde has a direct mount Jacobs Taper. Finding a new chuck is a matter of determining the taper on your machine. The chuck should have a number such as JT33 or JT2. That's the size of the taper. Find a chuck with the same number taper and you're good to go.

Here's a list of common machine tapers, which has a table of Jacobs Taper sizes to help you identify your chuck:

http://en.wikipedia.org/wiki/Machine_taper

 

[Alan R]

Look at the chuck closer should specify the taper. The female taper in the chuck and it's corresponding shaft are a Jacob's taper you should see ST followed by one or two number. You need to find a chuck with the same taper, they are common in precision machining and drill presses.

Great answer - easy enough -thank-you!

Guess I didn't do the right kind of research.

 

[Alan R]

Enco, and many other online machine tool sellers have a wide variety of chucks that come with tapered shafts.

Just checked Enco - good resource - thanks much.

 

[ImportTuner]

The new Jacobs chuck in the Enco catalog are all from China; the Rohm is made in Germany and very high quality

 

[Alan R]

It sounds like your spinde has a direct mount Jacobs Taper. Finding a new chuck is a matter of determining the taper on your machine. The chuck should have a number such as JT33 or JT2. That's the size of the taper. Find a chuck with the same number taper and you're good to go.

Here's a list of common machine tapers, which has a table of Jacobs Taper sizes to help you identify your chuck:

http://en.wikipedia.org/wiki/Machine_taper

Hey, thanks for the instruction. As I said to Metaleltr above, I obviously didn't put enough, or at least the right kind, of time into this. There is no number or other ID next to the "Multicraft" on the large barrel of the chuck, but there are letters/numbers stamped into the smaller head that holds the jaws - as the "surface" rust was so bad, I'll have to spend more time cleaning this up to get the #'s.

Great help - thanks again.

 

[spongerich]

If you measure across the open end, you should be able to reference the bore to the size of the taper.

See: http://www.victornet.com/reference/Morse_Jacobs.html

I've got several Jacobs chucks in various tapers and sizes.. PM me if you figure out what you need and I'll take a look and see if I have a match.

 

[Alan R]

The new Jacobs chuck in the Enco catalog are all from China; the Rohm is made in Germany and very high quality

How are we "newbies" supposed to know this stuff. I'm only interested in fixing this the right way.

Thanks a lot.

 

[Alan R]

If you measure across the open end, you should be able to reference the bore to the size of the taper.

See: http://www.victornet.com/reference/Morse_Jacobs.html

I've got several Jacobs chucks in various tapers and sizes.. PM me if you figure out what you need and I'll take a look and see if I have a match.

Hey thanks. I just got the right key for this chuck, and I'm not too happy with the wear on all 3 of the pilot holes. I'll have to dig the micrometer out.