Problems With Live Center

[texasfootball21]

I am looking forward to starting to turn between centers and I purchased some centers from John, a member here, who has been more then helpful in assisting me through the transition from the mandrel to a better method. If you are considering buying centers I definitely recommend John and would definitely buy from him again.

I am having a bit of trouble getting my old live center, the stock one from Jet, off my tail stock. I know you are supposed to bring the center in quickly and it should force the old one off. This is not working with my lathe.

I also tried to tap the thing off with another piece of metal and it took off the actual center's head off and left the other part behind.

I am looking for advice on how I should get this thing off my lathe.

Moderators: This is my first attempt to post pictures to this site so please, if I did it wrong, let me know. I am not sure exactly how I was supposed to post them and I didn't want to post full sized images so I went with thumbnails.

Thanks in advance.

 

[cowchaser]

Should just be able to retract it (make sure lock screw is loose) all the way back into the tailstock and it will pop out. It does take a little bit of umph. When your tailstock wheel stops turning easily just give it some more pressure and it should pop out.

 

[texasfootball21]

Should just be able to retract it (make sure lock screw is loose) all the way back into the tailstock and it will pop out. It does take a little bit of umph. When your tailstock wheel stops turning easily just give it some more pressure and it should pop out.

This is the method described in the manuel, and it is not working. Are you suppose to loosen the lock screw enough to where the quill spins around freely or just enough to where it can retract?

Any help appreciated.

 

[lwalden]

On my Jet mini, I've found that it's not uncommon for me to have to retract all the way into the tailstock, lock the lock screw, and use the same rod I use through the headstock to tap out dead centers going through the back of the tail stock to tap mine out. I'm assuming it's universal that there is a hole drilled through the center of the tailstock on other Jet lathes where you can do this as well?

 

[lwalden]

cutting torch?

 

[Tony Pridmore]

I once put a live center with a short MT2 taper in my big lathe and it would not eject. Luckily the fix was simple. I removed the quill and hammered the live center out from the other end using a round piece of steel (5/8 IIRC). Removing and replacing the quill was very easy on that lathe. I held the quill with my left hand and turned the handle on the tailstock with the right hand until it was free.

I haven't had the quill out of my Jet mini, so I don't know if the same would work. If you go this route, be very careful with the hammering. You don't want to burr the morse taper.

 

[Randy_]

This is the method described in the manuel, and it is not working. Are you suppose to loosen the lock screw enough to where the quill spins around freely or just enough to where it can retract?

Any help appreciated.

It is "NOT" necesasary to loosen the TS spindle lock very much......just a half turn or so until the spindle is loose. Turn the handwheel counterclockwise until is stops. This point occurs on my lathe when about 3/16" of the spindle still protrudes from the face of the TS. Then grab the handwheel with your entire hand and twist is counterclockwise another 1/8-1/4 turn and the LC should pop out. If it is really wedged in, it may take a fair amount of twisting force. I see from your picture, your lathe has seen quite a bit of use and the LC may have been in place for a long time. You might want to give the LC shaft a squirt of WD-40 and let it sit over night. If it is rusted in the MT socket, it is possible that you may need to disassemble the TS and use some aggrerssive disassembly techniques. A brass drift and a hammer may do it or you may need to add some heat. Just be careful not to anything that will damage the TS or any of its parts as they will be expensive to relpave.​

Note: If there is only about 1/16" of the spindle protruding when the handwheel first stops, it is probably fully retracted and there some other problem that will require the TS to be disassembled. (maybe a short LC?) ​

 

[Randy_]

I once put a live center with a short MT2 taper in my big lathe and it would not eject. Luckily the fix was simple. I removed the quill and hammered the live center out from the other end using a round piece of steel (5/8 IIRC)......

Actually, there may be an even easier way depending upon the design of your LC. Take a piece of hard wood about 1-1/2" wide or whatever is necessary and place it between the back face of the live center and the face of the tail stock. Then twist the handwheel counterclockwise and the LC will pop out as it tightens up against the piece of wood.

 

[fernhills]

I had that happen to me to, i just turned the handle til the quill was extended some and used the rod to hammer tap on the back of live center and it worked loose. After that it always comes off the traditional way now. When you put your new #2 whatever in i always extend the quill some because some of the #2`s are a bit longer and hit the back.

 

[rherrell]

The taper on your live center is too short, turning the handwheel won't work. Knock it out from the back with a fatter piece of stock, the piece you used the first time was too skinny and just knocked out the center of the center,of the center,of the center,of the center.:biggrin::wink:
If you get a longer M2T, instead of having it stick WAY out, grind a little off until you can retract it to the"0" mark on your quill without it popping off.

 

[Randy_]

The taper on your live center is too short, turning the handwheel won't work. Knock it out from the back with a fatter piece of stock, the piece you used the first time was too skinny and just knocked out the center of the center,of the center,of the center,of the center.:biggrin::wink:

Rick: He said it was the stock LC that came with the lathe so unless it is defective chances are it is not too short; but rather just stick from being in place too long. I missed this the first time I read his post and looked at the picture, myself. Typically when people have this problem, they just knock the little tip out of the live center; but notice in this case, he actually managed to knock the entire head assembly off of the MT arbor so it must really be solidly stuck.​

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As to the advice to use a larger drift, that is actually not the way to go. The hold in the handwheel is 3/8" in dia and if you use a drift that is that big, there is no wiggle so the drift is aimed directly for the hole in the arbor and will not catch the end of the arbor and drive it out. What you actually need to do is use a smaller drift, say 1/4" to you can angle it in the handwheel hole a little and catch the end of the arbor and drive it out.

The knockout rod that comes with the JET mini is 5/16" in diameter and is a little too big to be angled enough to securely catch the end of the arbor. It does just barely catch the end of the arbor; but I think it would slip off if the arbor is severely stuck as this one seems to be.

Joe: Carl's comment got me to thinking so I double checked. If you cannot get the arbor loose using the method I mentioned above, it is easy to remove the spindle from the TS and then should be much easier to drive the arbor out of the spindle.

Loosen the spindle lock five or 6 turns...even take it all the way our.....and then crank your handwheel clockwise until the spindle quits extending from the TS. At that point you will be able to remove the spindle from the TS or if it won't come out twist the handwheel another 1/4 turn.

Now that the spindle is out of the TS, it is an easy matter to put a big drift.....1/2" or 9/16".....in the end of the spindle and drive out the arbor. You do need to be a little careful here as a couple of bad things could happen. There are a couple of ways to drive out the arbor depending upon what tools you have available to you.

First thing to try would be to just grab the spindle with a gloved hand and pointing the arbor in a safe and soft direction, try to drive it out with a hammer. It would be better to use a wood dowel or a piece of brass or aluminum stock for your drift; but use whatever you have that will fit. If that doesn't work.......

Drill a 3/4" hole in a block of wood. Stick the protruding end of the arbor in the hole and using your drift and hammer, try, once again to knock out the arbor.

If that doesn't work, there are some other things that can be done; but they require a little more mechanical skill and possibly some additional tools. I would like to assess your mechanical aptitude a little before proposing more advanced techniques and hopefully one of the above methods will have worked so we don't have to break out the serious bag of tricks.​

 

[JimB]

Is it possible you got some CA on it and it's glued in? Maybe some acetone would do the trick.

 

[texasfootball21]

Rick: He said it was the stock LC that came with the lathe so unless it is defective chances are it is not too short; but rather just stick from being in place too long. I missed this the first time I read his post and looked at the picture, myself. Typically when people have this problem, they just knock the little tip out of the live center; but notice in this case, he actually managed to knock the entire head assembly off of the MT arbor so it must really be solidly stuck.​

​

​

As to the advice to use a larger drift, that is actually not the way to go. The hold in the handwheel is 3/8" in dia and if you use a drift that is that big, there is no wiggle so the drift is aimed directly for the hole in the arbor and will not catch the end of the arbor and drive it out. What you actually need to do is use a smaller drift, say 1/4" to you can angle it in the handwheel hole a little and catch the end of the arbor and drive it out.

The knockout rod that comes with the JET mini is 5/16" in diameter and is a little too big to be angled enough to securely catch the end of the arbor. It does just barely catch the end of the arbor; but I think it would slip off if the arbor is severely stuck as this one seems to be.

Joe: Carl's comment got me to thinking so I double checked. If you cannot get the arbor loose using the method I mentioned above, it is easy to remove the spindle from the TS and then should be much easier to drive the arbor out of the spindle.

Loosen the spindle lock five or 6 turns...even take it all the way our.....and then crank your handwheel clockwise until the spindle quits extending from the TS. At that point you will be able to remove the spindle from the TS or if it won't come out twist the handwheel another 1/4 turn.

Now that the spindle is out of the TS, it is an easy matter to put a big drift.....1/2" or 9/16".....in the end of the spindle and drive out the arbor. You do need to be a little careful here as a couple of bad things could happen. There are a couple of ways to drive out the arbor depending upon what tools you have available to you.

First thing to try would be to just grab the spindle with a gloved hand and pointing the arbor in a safe and soft direction, try to drive it out with a hammer. It would be better to use a wood dowel or a piece of brass or aluminum stock for your drift; but use whatever you have that will fit. If that doesn't work.......

Drill a 3/4" hole in a block of wood. Stick the protruding end of the arbor in the hole and using your drift and hammer, try, once again to knock out the arbor.

If that doesn't work, there are some other things that can be done; but they require a little more mechanical skill and possibly some additional tools. I would like to assess your mechanical aptitude a little before proposing more advanced techniques and hopefully one of the above methods will have worked so we don't have to break out the serious bag of tricks.​

I went ahead and took the quill out and banged it out, thanks for the tip and all who helped. Now I can ditch my mandrel forever, well except for slimlines.
Thanks again!

 

[rherrell]

You're absolutely right, Randy. It just never occured to me that someone would neglect their machine to that point.