Chuck Key

[Pip]

Just aquired a drill chuck marked: "Jacobs USA 34-02 2 Taper 0-1/2 in
0-13mm CAP" on the body and "Jacobs chuck arbor 2mt 2jt England" on the tapered shaft.

Unfortunately there isn't a chuck key with it, would I be correct in thinking that a Jacobs key no.3 (or 3c) will fit this chuck?

Does 2mt 2jt England mean that "jt" was the English version of mt?

Also, does the word "England" mean the arbor was made in England to fit this chuck, or was it made in U.S.A. to an English pattern? and is it possible to split the arbor from the chuck body? (don't want to leave vice marks)

Sorry for all the questions but it's roused my curiosity!
T.I.A.
pip

 

[CHJ]

Does 2mt 2jt England mean that "jt" was the English version of mt?

No JT refers to the taper size that fits in the back of the chuck, and yes the chuck should part from the morse taper shank.
Need to do it with care and correct support so as not to damage rear of chuck and preventing dis-assembly of chuck for maintenance.

See here , down the page for info.

 

[9fingers]

JT 2 means Jacobs taper no2, this is the female taper in the chuck.

I have a number of no 34 chucks and I'm pretty certain they are JT6.

Key K3 fits my no 34s

To remove an arbour, you need a pair of special U shaped wedges. Or drill a hole in the body through from the jaws end, tap a thread say M6 and use a bolt to tighten on the end of the arbour and then hit the bolt smartly square on with a hammer and catch the arbour on a soft cloth.

hth

Bob

 

[Pip]

Thanks guys, jt=Jacobs taper, "Simples", why didn't I think of that?
CHJ thanks for the link, interesting reading.
9fingers, thanks for the info, don't think I'll bother taking it apart, with my track record if I leave it alone it'll work longer
Thanks again,
pip

 

[dickm]

I've got a big Jacobs chuck which is on a No 3 taper. Have tried wedging it off to replace with No 2, but no joy. Peering in to the end of it, it looks as if there might be some sort of socket head screw in the back of the chuck, possibly tapped into the end of the arbor. Is this likely, as it's difficult to see clearly what might be there.
Any suggestions (about the chuck ) welcome.

 

[CHJ]

I've got a big Jacobs chuck which is on a No 3 taper. Have tried wedging it off to replace with No 2, but no joy. Peering in to the end of it, it looks as if there might be some sort of socket head screw in the back of the chuck, possibly tapped into the end of the arbor. Is this likely, as it's difficult to see clearly what might be there.
Any suggestions (about the chuck ) welcome.

Yes it is quite possible that there is a safety screw in the chuck, it will be left hand thread.

 

[dickm]

Yes it is quite possible that there is a safety screw in the chuck, it will be left hand thread.

Ah - another complication

 

[9fingers]

I've not come across a safety screw in a chuck with a female taper.

They are however common, if not standard, on chucks with a female thread in the back.

Bob

 

[Aled Dafis]

If you're still after a chuck key, Chronos have a range. From what I can make out, you just need to specify the diameter of the chuck key pin. They're not expensive, so it's worth a punt.

http://www.chronos.ltd.uk/cgi-local...___Jacobs___Others_136.html#aS_2e_2e#aS_2e_2e

Cheers

Aled