Thread: Which 2MT-JT6 Arbor do I need?

I am in the same boat as you, my dead centre that came with the lathe also doesn't have the tang, but the MT2 for my drill chuck does.

It still fits, but you can't wind the tail stock back as far before you hit the end, or eject the drill chuck.

BTW, I think McJing might have those cheaper, might pay to check them out.

Just checked them..........no, same price.

Thanks Big Shed, I just had a look at the McJing site and there are ones listed below the "with tang" ones called "with drawbar". The photo is only small but the shape looks more like my current dead centre.

http://www.mcjing.com.au/engineering/chuck/chuck.asp

Originally Posted by John H

Thanks Big Shed, I just had a look at the McJing site and there are ones listed below the "with tang" ones called "with drawbar". The photo is only small but the shape looks more like my current dead centre.

http://www.mcjing.com.au/engineering/chuck/chuck.asp

Missed those!

Just means they have an internal threaded hole in the end and no tang, so shorter, must get one of those,
thanks.

Edit,

Hmm, just looked at the specs they are both 105mm long, so maybe not.

Hmmm, clear as mud

So they are basically the same then?

Originally Posted by John H

Hmmm, clear as mud

So they are basically the same then?

Certainly the length is the same according to the specs, so it doesn't overcome the tailstock travel problem.

The tang is designed as a positive drive for rotating spindles to drive the taper and stop it from spinning inside the spindle ,It wont make much difference in a lathe tail stock whether you use a taper with a tang or not ,as the lathe tail stock most often doesn't have the slot down inside to accomodate the tang ,they are usually bored deeper.
Some earlier lathes did have the tang slot and a hole right through the tailstock spindle to use a drift to dislodge the tapered sleeve or drill chuck.Mostly these days they are auto eject.

Kev.

I was using a spare chuck from my drill press in the tailstock of the lathe. It had a tang and that restricted the usable travel of the tailstock, so I just ground it off. No problems except that now I can't put it back in the drill press or I won't be able to get it out!
Cheers
Graeme

Be aware that the drawbar engages only the MT, to (try to) prevent auto-disengagement when withdrawing the bit. Auto-disengagement can still occur at the JT. DAMHIKT.

Joe

Run your tailstock shaft all the way out. If it has a sideways slot cut in it it has a morse taper with tang socket.
If it has no sideways slot it should not have one as it would be difficult to machine it in any other way but still could have a tang socket and just eject with full withdrawal of the shaft .
You really need to shine a strong light into the socket and see if it has a slot at the base of the taper. Take the tailstock off the lathe if necessary.

With the item in the original post, there are two tapers operating.

#2 Morse taper is the long taper to mount into the tailstock.

JT6 is the short taper on the nose to mount a chuck, hopefully permanently.

Unless you have a chuck with a JT6 socket to dedicate to the arbor, you need an arbor that matches the chuck, which might be threaded or have a tapered socket. It's best to source the chuck and arbour together to ensure a match. The critical issue is to get an accurate chuck with good grip capabilty and an arbor to adapt it to the tailstock. Tang can be removed with a RA grinder and cut off wheel if need be, provided that you neatly dress the cut before attempting to install the MT into the tailstock socket, As mentioned previously, if you remove the tang, the chuck and arbor are not particularly well suited for a drill press as they can't be ejected by means other than gravity.

I have a JT6 chuck that will spend the rest of its life on the arbor for sole use in the tail stock.

I guess I'll get one of the tang arbors and cut the tang off. Thanks for all the advice

Most small to medium sized lathes don't have tang receivers in the tailstock, unlike the heavy iron, but will accept arbors with or without the tang. In my case (H&F AL320G), my drill chuck arbors all have tangs and eject when the barrel is completely pulled back into the TS. My live centre on the other hand doesn't have the tang and will not eject from the barrel - I have to use a collar to get it out.

You need to measure the depth of the taper in the TS barrel and compare that to the length of the taper on the arbor with and without considering the tang part of the length to see whether it will eject once you've cut the tang off.

The arbors with threaded ends are primarily intended for use in mills where a drawbar runs through the centre of the spindle.

Well, I picked up an arbor with a tang and just ground it off. Works like a charm.