Lathe tailstock slipping

[Rick M]

Last fall I bought a Delta 46-111 which I repainted but hadn’t gotten around to using until today. Problem I’m having is the cam vibrates loose allowing the tailstock to slide backward on the bed and the workpiece comes loose. I took the tailstock apart and cleaned off all lubrication and cleaned all wax off the bed, it still happens. Any suggestions?

 

[Mike Davis]

There should be some adjustment where the cam contacts the bed. Not sure how that one works, I'd have to look at it.

 

[KenOfCary]

Like Mike said there should be a nut or some other way to tighten the Washer that locks up under the ways when you tighten the CAM lever. That would allow you to tighten the lever more tightly. If that doesn't work maybe the Washer is warped or too small and needs to be replaced by a beefier one.

 

[Rick M]

The two nuts are set where they were by the factory but I will try loosening them and see if that helps.

 

[CDPeters]

I think you may need to tighten them a smidge. If they don't already have them, use the nylon insert lock nuts to keep them from loosening over time.

 

[KenOfCary]

The CAM doesn't look worn, so adjusting the screws tighter should work. (the operative word being 'should') You said you cleaned oil and wax from the ways, but did you also do so from the bottom of the ways. That would be where the square plate (not a washer in this case) engages the ways to lock the tail stock.

 

[Rick M]

I'll try it both ways, tightening and loosening.

I did clean both and top and bottom, first with lacquer thinner then a degreaser. The Nylock nuts are a good idea. The factory had Loctite on there but I had to bust it off to repaint.

 

[Roy G]

Rick, the bed may be too smooth. David Ellsworth recommended put some sawdust from green wood on the bed overnight to let it rust. Then clean it off and sand with fine sandpaper. This will leave a "tooth" for the tailstock to grab. When I saw Rude Osolnik give a demonstration, he would always give the tailstock locking lever a whack with the handle of his tool to give it a final tighten up.

Roy G

 

[Rick M]

Fixed. 1/2 turn on each nut to loosen the cam a bit and it is rock solid. So stupid. I could have fixed it in less time it took to ask the question. I guess my frustration with it last night blinded me to the obvious solution. Thanks everyone for the help.

 

[aplpickr]

When tightening the nuts, make adjustments by moving one half nut face at a time. Using a file laid FLAT, file the bed Flat. Go across both ways at the same time. Any bright spots were high which lessens total contact. Also file the bottom of the tailstock contact spots. The big question is: Why do you have that much vibration? Do you have BAD spindle bearings or tailstock bearings? Turn an extended handle for the tightening handle. Drill a matching hole that will slip over handle and fill with five minute epoxy. Another three or four inches should double the leverage! My wife who has weak, carpal tunnel hands has every adjustment handle on her lathe extended. Cast iron cures over years. Things need to be flattened every year or so for many years. Many lathe makers allow bare castings to weather outside for five years before final machining. Rust mills off easily. Many mini lathes use a large washer as the friction plate on the tailstock. Very little contact!. Fabricate a plate that will go between the ways, you will have ten times the surface contact!

 

[Rick M]

Bad belt. The belt is in terrible condition (thump, thump, thump, as it goes around) plus the Rockwell sheet metal stand is a backstage thunder machine; all that and my shop floor is wood frame construction so the whole place rock and rolls until I get above 2000 RPM. I inspected the bearings and they appear fine to me although there is something that occasionally makes a squawk but I need to replace the belt before troubleshooting anything else.

 

[aplpickr]

Test the bearings while running. Take the biggest gorilla screwdriver that you own. 18" is best. Place the point against the safest place near the bearing. Place the end of the handle against your ear flap. Close the flap over your ear canal. For safety, let somebody else switch the lathe on/off. Any noise other than a smooth whir is a bad or about to be bad bearing. Check both front and back of headstock and motor. Screeches, clunks, grinds, pops, scrapes, etc are all BAD!

 

[KenOfCary]

I keep an old stethoscope in the shop for such purposes. Mine came from an old blood pressure test setup before I upgraded to an automated cuff machine, but you can buy one on smile.amazon.com for less than $10. Seems safer than a screwdriver.

 

[Rick M]

I have an automotive stethoscope, I'll use that.
-- Rick M

 

[Rick M]

Update, the bearings are toast. I started messing around after replacing the belt and it sounds like a cat in heat. I'm going to order new bearings but I'll need some sort of bearing puller. Any suggestions? I need to change bearings on a bandsaw too so the puller will get more use.

 

[aplpickr]

Rick, while installing the new bearings, only push on the race that is under friction. An assortment of deep wall sockets and pipe nipples is very useful for this. Pushing on the other race can scar the balls or rollers. A microscopic nick will seriously shorten the bearings life. Depending on the lathe and which bearing, sometimes you push on the inner race, sometimes on the outer. Most automotive machine shops will press bearings on or off for a small fee.

 

[Woodman2k]

Rick,
hit the auto parts stores, or Sears. Lowe's used to carry them but they needed the room for the 50 flavors of hand soap they would rather carry.

 

[Endless Pursuit]

Harbor frightful actually has a decent quality puller kit for a great price.