Question About Jacobs Chucks

[Anthony G]

I went to the hardware store today, one of the couple that are still left in my city since most of them closed up. I needed a couple bolts. Anyway, while I was in there I was looking around and I noticed some Jacobs chucks in a locked display case they had. Just out of curiosity I ask the guy if he would check to see what kind of a mount they were. I was sure they were threaded mount, but could tell because the case was behind a counter and too far away. Anyway, they were threaded mount, I think maybe 3/8"-16. The thing about these is that these were OLD chucks. I can't say they had an inch of dust on them (yes, even in the display case), but they had a LOT of dust on the packages. The are USA Jacobs chucks. All of them. They are $11.00. Two of them were keyed and one was keyless.

I guess my question is how accurate are threaded mount chucks? I know I can buy an arbor for them from ENCO or elsewhere with the threaded mount for the chucks and the MT2 taper for a tailstock. Would it be worth it? These are old, USA Jacobs chucks. I bet these are 20-25 years old. The guy acted like he didn't even know they were down there.

 

[JimDawson]

Unless you are working for NASA, I would say that a threaded chuck would work fine. Not quite as heavy duty as a taper mount, but plenty strong for most work within the range of the chuck. Sounds like a deal to me. I would buy all of them.

 

[4GSR]

Man, jump on them!

I have a two that I bought for next to nothing with no. 2 Morse taper shanks that were NOS chucks that nobody wanted because they were threaded mount. They work fine on my SBL.

 

[chips&more]

I have a feeling they are replacement drill motor chucks. Which means they are not made to the quality standards of a machine chuck. But, it all depends on your use/needs/finances. And be aware that a threaded chuck could un-screw. Might want to Locktite the threads to be safe…Good Luck, Dave.

 

[Anthony G]

"Chips".............I'm sure they are replacement drill motor chucks. Just wondered if they would be "OK" mounted on a threaded arbor for my tailstock. I would think as long as I use right hand drills, unscrewing wouldn't be a problem. Might be OK for secondary, utility chucks, huh? I think they're 3/8" capacity.

 

[Charles Spencer]

I'd buy them in a New York minute. I think they'd work well if you made a threaded 5/8" sleeve and fit them into something like one of these:

http://www.grizzly.com/products/Tailstock-Turret-MT2/G9318

I have one and also a flat, capstan I guess, version. A smaller drill chuck would work better than a larger one in these. True it would lack rigidity but it would probably work OK for center drills, pilot holes, etc.

 

[Bill C.]

"Chips".............I'm sure they are replacement drill motor chucks. Just wondered if they would be "OK" mounted on a threaded arbor for my tailstock. I would think as long as I use right hand drills, unscrewing wouldn't be a problem. Might be OK for secondary, utility chucks, huh? I think they're 3/8" capacity.

Now days most drill motors are reversible, they should work just fine. Like someone posted earlier use a drop of Loctite if in doubt.

 

[T Bredehoft]

I have about half a dozen small Jacobs chucks, salvaged from drill motors, all mounted on 3/8 24 threaded M1 Tapers for my little lathe, I can set up center drill, tap drill, tap, reamer and a couple of others to make multiple operations on pieces in the lathe. I've had no problem with them unscrewing when backing out a tap.

 

[hman]

Reversible drill motors typically have a left-hand thread in the spindle, usually something like a #10. A LH screw is driven in from inside the chuck and keeps it from unscrewing in reverse.

Of course, if you're using the chuck on a drill press, reversing will not be an issue. Do the chucks have a large enough capacity for use in a drill press? If so, I'd say "go for it!"

 

[Anthony G]

Reversible drill motors typically have a left-hand thread in the spindle, usually something like a #10.

But the outer thread is right-handed, correct? That would be a problem since I haven't seen any arbors with left-handed thread.

Of course, if you're using the chuck on a drill press, reversing will not be an issue. Do the chucks have a large enough capacity for use in a drill press? If so, I'd say "go for it!"

The are 3/8" capacity, I believe. Not 100% sure, but relatively sure. I was sort of in a hurry to get out of there and back home. I think mostly I'd be using them in the tailstock of my lathe.