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Dave Crabbs
10-19-2004, 9:30 AM
Hi All,
I have trouble getting the drive center off my lathe. My lathe is a jet 1236 and had this problem since the day I got it. I have to use a dead blow hammer and beat the knock out bar (guessing that is what the bar is called to remove the drive) like I am trying to knock down a block wall. One time I shot the spur drive the length of the lathe. I have tried different drive centers and they get stuck too. The way I install wood to turn is I drive the spur into the work piece place the work piece and spur into the head drive and then engage the live center into the work piece. I also turned a pen (my first one :cool: ) and had a heck of a time getting the mandrel out of my lathe. Any ideas as to what I could do to make it easier to remove the drives or what my problem my be???
Thanks,
Dave

Dick Parr
10-19-2004, 9:37 AM
Dave you might want to get yourself a Tommy Bar. It sould save on the hammer. :D

http://shop.woodcraft.com/Woodcraft/product_family.asp?family%5Fid=4708&gift=False&0=dept%2Easp%2Cdept%5Fid%3D10000%26Tree%3D%2CDepar tments&1=dept%2Easp%2Cdept%5Fid%3D1030%26menu%5Fid%3D%26T ree%3D0%2CWoodturning&2=dept%2Easp%2Cdept%5Fid%3D2087%26menu%5Fid%3D%26T ree%3D1%2CAccessories%20%2D%20Woodturning&Gift=False&mscssid=9F53B079E3C84179AD4A56E4A84F4066

If the link doesn't work take a look at the Woodcraft site.

Good luck

Richard Allen
10-19-2004, 10:10 AM
Hi Dave

I would check the inside of the headstock spindle. It should be clean and shinny. Anything other than clean and shinny needs to be taken care of.

The taper you put into the headstock (spur or pen mandril) should be clean and smooth.

It is posible that the taper in the headstock spindle is bad. This is not very likely but posible.

Don't oil or lube anything.

Good luck

John Szarek
10-19-2004, 10:25 AM
You should not be tapping or forcing the Morse Taper in. A light flick should set it home. If it does not, you need to clean as said above.

Dave Crabbs
10-19-2004, 2:28 PM
I checked the headstock spindle and it was clean but has some light scratches I'm thinking from using the knockout bar.
You should not be tapping or forcing the Morse Taper in. A light flick should set it home. If it does not, you need to clean as said above. Nothing is driven into the headstock. I tap the spur drive into the end of the turning stock with a rubber mallet or dead blow hammer. I then use the tail stock ram to seat the live center. Could I be using to much force to seat the live center? It is a stock jet live center. I set it so the wood touches the ball bearing on the live center.

Jim Becker
10-19-2004, 2:51 PM
Dave, assuming that the tapers are clean, if there is any slight variation in the machining of the taper, it could lock "tighter" than you might want or expect. It should release with a sharp, but not excessive blow or two with the knock out bar. You may want to try a higher quality drive center, making the assumption that the taper in the spindle is "correct" and the center is "not".

You could also have a cap nut machined with a 7/8" hole in the end to allow you to use a wrench to lever the centers out of the spindle. You put the drilled cap nut on the spindle threads first and then insert the taper. When you are done using the spur center or other MT attachment, you just back off the cap nut with a wrench to pry the center free. (This is the method used for lathes, like the Poolewood, that do not have a hollow spindle)

John Szarek
10-19-2004, 2:51 PM
That could very well be your problem. At first I was doing the same thing and my live center jammed once. After that I marked my centers and tapped the live center on the tail of the workpiece and removed it. Then tapped it into place so I could just slide the whole thing onto the lathe.

I am having trouble finding the cleaning tool for a M#2 taper. Anyone know where, Woodcraft and Lee Valley have discontinued them.

John Shuk
10-19-2004, 11:42 PM
I've got the same lathe and have the same trouble sometimes. I find cleaning help. I'm thinking of getting the Taper Mate which fits right in there to clean out the gunk. I jsu get in as far as I can with a rag and a little power lube and it cleans out with out much trouble now. Hope this helps.

Dominic Greco
10-20-2004, 7:50 AM
Dave,
I used to have a Jet JWL-1236 and had that problem when I was first using it. The spur center jammed into the #2 MT of the headstock and would not come out. I ended up inserting a 3/8" steel rod into the headstock, making sure I was in contact with the back of the stuck spur center, and gave it a hearty "whack" with a small hammer. The spur center shot across the shop like a projectile!

I found that the most likely cause was some internal scoring in the Morse taper. I used a scotch brite and some 400 grit sandpaper to clean it up and it worked fine up until the day I sold it.

The knockout bar included with the Jet is a joke. I suggest getting a nice piece of 3/8" dia steel rod and using that. Or you can buy that knock out bar that Woodcraft sells.

Just a slight "rap", and the pen mandrel, spur center, or other #2 MT based accessory should pop right out. Frequent inspection and cleaning of the internal surface will really help to reduce the occurance of this problem.

John Szarek
10-20-2004, 10:12 AM
stores.ebay.com/XKUT

Sell finishing reamers for the morse taper. It will remove any burrs and polish up the inside. I asked and he posted the #2 that night. Nice to deal with. I know cleaning is different than polishing. It is designed to cut a new edge. I want to get the tapermate, but the #2 is not listed anywhere.[/color]

(btw, why is this all in green?)

"It's not all green - at least not any longer ;) I assume you pasted the code to make it green." :) :) (your friendly moderator)

Seth Bollinger
11-03-2004, 10:11 AM
I have a JML-1014 and have had the problem once or twice with my pen mandrel. I also took some 600 grit paper to the mandrel to make sure it was clean and I wipe out the headstock. I also keep either the spur drive or my pen mandrel in at all times so that I don't get a bunch of dust in threre when not in use.