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WaggaSteve
2nd November 2015, 10:04 AM
I have a Coronet CL3 which (took me a while to find out) has no through hole (dont know the right term) for either the headstock or tailstock. ie I cannot use a bar to tap out MT fittings like jacobs chuck. Means I am reduced to holding the items with pliers and wrestling the things out, marking (though not really damaging) them. Got a new jacobs chuck last week and took me nearly 15 mins just to get it out at the end od using it. Any suggestions on easier methods or techniques I am missing would be appreciated
Steve

Big Shed
2nd November 2015, 10:22 AM
Cut a hardwood wedge with a slot in that fits over the rear MT fitting and gently tap it in behind the Jacobs chuck.

WaggaSteve
2nd November 2015, 10:33 AM
Not sure I am understanding correctly. Do you mean a wooden slotted version of an MT 1 to MT2 adaptor type thingy. I do have an MT2 jacobs chuck (Coronet is an MT1) and could use the adaptor and that if it would help

Big Shed
2nd November 2015, 10:38 AM
Nope.

I mean a wooden wedge that will fit behind the Jacobs chuck with a slot that will fit over the exposed bit of the MT (MT1 or MT2) adapter. By tapping the wedge it will force the Jacobs chuck out of the MT.

Edit

Here is a link to the same technique using 2 metal wedges

https://www.google.com.au/search?q=wedge+morse+taper&num=30&safe=off&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAWoVChMInpnhwLLwyAIV5K-mCh3G2AVU&biw=1043&bih=623#imgrc=OjVnkL1rDcDsDM%3A

I am assuming you have more room behind the Jacobs chuck so a single hardwood wedge should work.

WaggaSteve
2nd November 2015, 10:45 AM
I have only used the new jacob chuck with MT1 once and was able to get the chuck off the MT (accidentally) but had trouble getting the MT out of the tailstock. Obviously they make the jacobs separately from the MT so one jacobs can fit either MT1 or MT2.
Sorry - just noticed the link. Whilst the MT is removable from the Jacobs, my normal live centre does not have a removable MT (or at least that I am aware of) so leaving the MT from the Jacobs in would preclude its use. My MT2 to MT1 adapter does have a slot like the 3rd row picture of the drill press. Maybe I should be using that with the shaped metal removal triangle thingy (he says getting technical. Assuming this is correct, are these a specialist item or just a shaped bit of flat metal

Mobyturns
3rd November 2015, 08:56 AM
Nope.

I mean a wooden wedge that will fit behind the Jacobs chuck with a slot that will fit over the exposed bit of the MT (MT1 or MT2) adapter. By tapping the wedge it will force the Jacobs chuck out of the MT.

Edit

Here is a link to the same technique using 2 metal wedges

https://www.google.com.au/search?q=wedge+morse+taper&num=30&safe=off&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAWoVChMInpnhwLLwyAIV5K-mCh3G2AVU&biw=1043&bih=623#imgrc=OjVnkL1rDcDsDM%3A

I am assuming you have more room behind the Jacobs chuck so a single hardwood wedge should work.

Good method to extract a Jacob's Chuck with only pitfall however - you may inadvertently extract the chuck from the Jacob's taper before the Morse Taper spindle becomes free of the MT socket. :( not good when that happens.

WaggaSteve
3rd November 2015, 09:52 AM
Exactly what happened !!!- hence the question. I assume it would be a bad thing to glue the taper into the chuck ??

Treecycle
3rd November 2015, 10:54 AM
Does this help at all?
362653

Dalboy
3rd November 2015, 11:46 AM
The newer CL3 comes with a thread protector which is also used to extract bits from the head stock MT. The tail stock has a through hole in which to put a bar into to knock out that end.
There is also a couple of flats on the shaft to put a spanner to get to them you need to take the belt cover off. So hold shaft with spanner put small bar into the protector and unscrew which will forced against the drive in the MT socket.

You can see it in this photo behind the 4 pronged drive

362657

greyhound
3rd November 2015, 01:11 PM
[QUOTE=Dalboy;1906297]The newer CL3 comes with a thread protector which is also used to extract bits from the head stock MT. The tail stock has a through hole in which to put a bar into to knock out that end.
There is also a couple of flats on the shaft to put a spanner to get to them you need to take the belt cover off. So hold shaft with spanner put small bar into the protector and unscrew which will forced against the drive in the MT socket.

You can see it in this photo behind the 4 pronged drive

362657[/QUOTEt]
I have a older model which was called a Cornet it also came with the ejector screw cap.
just screw it on before putting anything into the morse tapper and whew you unscrew it will eject what has been in the taper.

WaggaSteve
3rd November 2015, 01:36 PM
Thanks all but no equivalent mechanism on the tail stock and tail stock does not have a through hole on my model. Not sure of age but it is a Coronet CL3 not a Record if that makes any difference

WaggaSteve
3rd November 2015, 01:37 PM
useful and thank you - but not for this issue

Treecycle
3rd November 2015, 08:18 PM
Any reason you can't remove the tailstock thread completely and have someone drill a hole through from the back end. Once the hole reaches the cavity at the back end of the morse taper, a bar can then be put through the shaft and used to knock out the chuck. You will never have this problem again.
Not sure if the same thing can be done on the headstock shaft.

Alby123
3rd November 2015, 09:10 PM
The tailstock on the CL3 usually has a 5/16" hole in it allowing for long hole boring. Try and put a 5/16" diameter rod through the tailstock.

Paul39
4th November 2015, 04:05 AM
Steve,

If you can't work out a way to use a knock out bar, you might find a "pickle fork" tool at an auto supply store to fit.

Rather than hitting it with a hammer to drive between the MT part and spindle, gently wedge it in and work back and forth to ease the MT accessory off. It is not good to beat on a spindle as it can make small indentation in the ball race with the ball bearings. Shortly it will make expensive noises.

https://www.google.com/search?hl=en&site=imghp&tbm=isch&source=hp&biw=1024&bih=615&q=pickle+fork+tool+for+auto+tie+rod+work&oq=pickle+fork+tool+for+auto+tie+rod+work&gs_l=img.12...3436.26395.0.29993.48.12.5.31.36.0.257.1573.0j11j1.12.0....0...1ac.1.64.img..31.17.1592.yKaTAstKK68

This will not work with a drill chuck mounted with a Jacobs taper. You might find a chuck that screws on to a MT2 part.

I periodically oil up a male MT part and rotate in the female MT sockets on my lathe. This usually produces a little dirt and rust staining. I then cram a rag into the socket and rotate and wipe off the male part so they are clean and lightly oiled. This greatly facilitates getting them apart.

I have also found that if I turn a long time with a big spindle between centers, with a fair amount of pressure from the tail stock, the spindles and female MT sockets get warm and the male parts work in deeper. When everything cools down the sockets grip the male parts quite well.

This is made worse if there is a thin film or rust to provide a tooth to grip. It can be difficult to get them apart.

Some chucks have a drive center accessory that can be put in the chuck and gripped, so you don't have to deal with the MT.