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Stephen L King
07-16-2020, 8:51 AM
I was just given a older Craftsman lathe. Both of the centers are stuck. I looked up the manual on line and they say to back the nut off the spindle to remove the drive center which I tried after spraying it with penetrating oil. I have also tried tapping it from behind with a steel rod. Any other ideas?

John K Jordan
07-16-2020, 10:31 AM
I was just given a older Craftsman lathe. Both of the centers are stuck. I looked up the manual on line and they say to back the nut off the spindle to remove the drive center which I tried after spraying it with penetrating oil. I have also tried tapping it from behind with a steel rod. Any other ideas?

With things that are stuck from corrosion I douse with multiple doses of penetrating fluid (I use PB Blaster), set sit and occasionally tap sharply on the piece with a small hammer or something to "shock" it. If a little force after that doesn't work, I go with heat or cooling. Typically you heat the female part with a torch then try the force. This might cause a problem with the lathe, especially the headstock bearings and such. An alternative is to cool the male part. A can of "freeze spray" (sold at electronic suppliers) is good for small parts. Dry ice is better since it gets the temperature lower and works quickly. That and force, after the penetrant, might do it.

Or you might just need more force. I once tried for hours to remove a large tapered shaft (about 2" in diameter) on my skid steer. I tried penetrant, an industrial SDS hammer, pounding with a sledge hammer and couldn't budge it. I needed to get the bucket cylinder rebuilt so I finally loaded up the entire skid steer on a trailer and took it to the shop. When I picked it up I asked the repair guy how he got it apart. He said he smacked it with a hammer. He told me the next time use a bigger hammer! So when the other one went out a few years later I did! Hammer plus pulling with a chain binder plus penetrant.

JKJ

Kyle Iwamoto
07-16-2020, 10:55 AM
You have a hollow spindle? Mine did not. The rod should work. Just keep tapping, don't hit that with a hammer you could damage the spur, that metal is not that hard. If solid, when mine got stuck, I used an open end wrench just a bit bigger than the drive and put that between the drive and spindle. Hit that with a hammer it should pop free. In addition to what JKJ above said.

Stephen L King
07-30-2020, 12:17 PM
Okay I finally got a steel rod small enough to fit in the tailstock and the dead center came out with about three light taps. The drive center on the other hand seems to be stuck tight. I have -60 spray coming and will try that when it arrives, but should it be stuck that much harder then the dead center? I sprayed it with PB Blaster and let it soak. I even raised the head stock to let gravity help it penetrate.

Robert D Evans
07-30-2020, 4:36 PM
Don't force it. Get a bigger hammer.

Stephen L King
07-30-2020, 5:45 PM
I am already using a small sledge.

John K Jordan
07-30-2020, 6:32 PM
I am already using a small sledge.

If smacking on the spindle in the headstock I'd be careful about the bearings. Too much axial force can ruin a bearing (and break cast iron). If you can remove the spindle you can apply a lot of force to the rod without hurting anything. (I'd use a hydraulic press.) Otherwise, I might consider using the tailstock or something made from wood/metal to clamp to the the lathe and provide support to the spindle while hammering. This after soaking in PB Blaster for a day or two with occasional raps on the center.

Also, is there anyway to devise or use the threads to make a puller? Can apply a lot of force that way without hurting anything else. For example, if a big nut that fits the spindle threads will clear the drive center it might be used to push against a slotted plate or fork. Or is there enough gap to use a wedge type ball joint tool, a "pickle fork" like this? https://www.amazon.com/OEMTOOLS-25202-Ball-Joint-Separator/dp/B000CMJHCI (photo of the spindle and with drive center might be helpful)

Did you try the cooling? That has worked for me a time or two on stubborn parts.

Also might try a torch on the end. Both pieces will expand with the heat but the heating and cooling might break things loose. I've protected sensitive components by wrapping with strips of terrycloth soaked with water.

JKJ

Brice Rogers
07-31-2020, 1:00 AM
On my various lathes and drive centers, there has been a space between the end of the spindle and the head of the drive center. Consider making something like a "pickle fork" (automotive term for a tapered U-shaped wedge used to remove a tie-rod end). They are usually driven in to force out the stuck piece. The wedge shape gives you the mechanical advantage. If you make two tapered U-shaped wedges, you can use a hefty C-clamp to get them to work together, essentially multiplying the mechanical advantage.

IMHO, if you are using a sledge hammer to remove a stuck drive center, strongly consider replacing the bearings when you're done. They aren't that expensive and can be damaged during hammer events. A safer but more lengthy approach would be to remove the spindle (and bearings) and use a hydraulic press to push out the stuck piece. Also, with the bearings off of the spindle shaft, you can heat the spindle a little higher. I think that most spindles (but I could be wrong) are not made of hardened steel. So bringing them up in temperature to 400-600 F should NOT be an issue. If others think that I'm wrong, please opine - - I don't want to mislead the original poster.

Stephen L King
08-04-2020, 12:05 PM
Thanks for all the help I finally got the drive center out last night. I warmed it up slightly with a torch and then hit it with -60 spray and then slid a pickle fork in behind it and after about three hits with a hammer on the fork out it came. The drive itself had a lot of surface rust on it, but it cleaned up nicely. I cleaned out the spindle with cotton balls soaked in PB Blaster and held in forceps. Now I just need to find some practice stock and find out how much I remember from the little bit of turning my grandfather showed me fifty years ago.

John K Jordan
08-04-2020, 2:12 PM
Thanks for all the help I finally got the drive center out last night. I warmed it up slightly with a torch and then hit it with -60 spray and then slid a pickle fork in behind it and after about three hits with a hammer on the fork out it came. The drive itself had a lot of surface rust on it, but it cleaned up nicely. I cleaned out the spindle with cotton balls soaked in PB Blaster and held in forceps. Now I just need to find some practice stock and find out how much I remember from the little bit of turning my grandfather showed me fifty years ago.

Great!

Don't remember if you said where you live (if you put it in your profile it will be with every message) but there may be people near you willing to give you practice wood. I keep tubs of it here for anyone who needs it.

JKJ

Stephen L King
08-05-2020, 8:32 AM
I live in a little town called Overbrook Just South and East of Topeka KS. We are not close to much of anything.

Thomas L Carpenter
08-05-2020, 10:21 AM
You have a hollow spindle? Mine did not. The rod should work. Just keep tapping, don't hit that with a hammer you could damage the spur, that metal is not that hard. If solid, when mine got stuck, I used an open end wrench just a bit bigger than the drive and put that between the drive and spindle. Hit that with a hammer it should pop free. In addition to what JKJ above said.

My old Craftsman has a hollow spindle and it has a long steel rod with a small Piece of brass attached to the end. A couple raps with a hammer works well. Don't know if the rod came with the Craftsman or my Dad made it specifically for getting stuck centers out.

Stephen L King
08-05-2020, 10:54 AM
The manual I found online says that there is supposed to be a spindle lock hole on the head stock that you can stick something in to lock the spindle remove faceplates etc. The only thig I can find is the indexing pin, which is not very big and It says not to use it for that. Any ideas on how to lock the spindle without one?

Dwight Rutherford
08-05-2020, 11:36 AM
This is a new topic, suggest you start a new thread. More will read it.