What's new
What's new

Lifting a lathe, by the chuck?

ossi

Aluminum
Joined
Mar 6, 2003
Location
Iceland
Was actually suggested to me by Knuth in Germany.
I have to lift my Knuth lathe,1250lbs, about an inch. Just to get the pallet from under it.
The easiest way would be to put a strap around the chuck spindle and use a hand winch to lift it that one inch for a few seconds while dragging the pallet from under it.
What do you think, safe?
 
A guy I know that does rigging told me that the strongest part of the lathe is the spindle, and that he lifts them by the spindle constantly. I personally don't have a nice hoist so i use the fork lift under the bed, But I have mooved my small take by the chuck with an engine hoist several times with no troubles.

I don't know how true his statement is, but thats what he does and i do it with my small machine.
 
My machines mean far too much to me to even consider doing that.

I'd move the tailstock and saddle to the far right side of the bed and use a lifting strap around the bed up near the headstock. Lift a little to check balance, adjust tailstock and bed accordingly to level. May even have to add some weight (securely) to even things out.

My 2 cents, knn
 
i know a lot of dealers lift leathes by the chuck. i lifted my "big" lathe using a strap around the bed, as specified by the manufacturer. on the other hand a tapered bearing as small as 30/62 mm has a capacity of around 4.5 tons. but im with knn on this one.
 
Jamie's rigger friend is correct. The sppindle is possibly the ruggedest built parts of a machine tool.

I can understand why people would shy away from hanging the machine's weight on the spindle (pass a sling behind the chuck, mind, not a bar sticking out a foot. weight, not leverage).

The spindle is designed to survive the biggest collision loads possible.

Look up the load ratings of the bearings. Look at the way the head stock is attached to the bed with big bolts. Look at the casting beef around the spindle bearings and the proportions and materials of the spindle.

Nope, a lift with a sling behind the chuck won't hurt a lathe spindle. Unless the sling was 7/8" wire and the lathe bolted down
 
"Look up the load ratings of the bearings. Look at the way the head stock is attached to the bed with big bolts. Look at the casting beef around the spindle bearings and the proportions and materials of the spindle."

Don't do this with a hardinge. The bed is mounted to the cabinet with a three
point kinematic mount, held down with sturdy springs. Cabinet is as heavy as the
bed and headstock put together - this is all true for HLVHs, DV-59s, chuckers, etc.

I'm sure the load ratings make sense. But anyone who's ever installed a spendy
set of spindle bearings in a lathe, or replaced the shells in even a southbend machine,
will waffle quite rapidly when somebody suggests hanging the machine from their
new set of bearings!
 
Just a quick "learing experience" story .... When i was 19 and working in my first real machine shop I was changing chucks on the largest lathe I had used up to that time. About a 20"x80" machine. Anyhows... I screwed the lifting ring into the chuck, hooked up the joist and pulled off the chuck, dropped it, scooped up the 4 jaw and put it on. As I was going to lower the joist to take the slack out so i can unhook it, One of the guys in the shop let one of the biggest farts rip that i have ever heard in my life, Causing me to turn and looke. I hit the wrong button on the hoist, and when i turned around, the lathe was about 2 feet off the ground. I really shit a brick and set it down as fast as i could. After that it still worked great and i didnt notice any difference in tolerences or noises. Now I look twice at the UP and Down buttons.
 
Just a quick "learing experience" story .... When i was 19 and working in my first real machine shop I was changing chucks on the largest lathe I had used up to that time. About a 20"x80" machine. Anyhows... I screwed the lifting ring into the chuck, hooked up the joist and pulled off the chuck, dropped it, scooped up the 4 jaw and put it on. As I was going to lower the joist to take the slack out so i can unhook it, One of the guys in the shop let one of the biggest farts rip that i have ever heard in my life, Causing me to turn and looke. I hit the wrong button on the hoist, and when i turned around, the lathe was about 2 feet off the ground. I really shit a brick and set it down as fast as i could. After that it still worked great and i didnt notice any difference in tolerences or noises. Now I look twice at the UP and Down buttons.

Funny how sh!#ing one's self can be contagious! :D
 
Thank you all for your quick replies.
As I feared some of you managed to frighten me, so Im gonna have to grab a Heineken and think about it overnight.

Thanks again.
 
Uh, bearings are rated at rotational loads with proper lubrication.

Pick a heavy lathe by the chuck or spindle and you will brinnel the races that are under the couple of rollers that are in contact with the races. Then, sometime down the road after use, the bearings will start failing due to the brinelling.

Go to SKF or another website and research bearing failures and read up on brinelling.

I have seen this in action, with brand new machinery that was improperly rigged and shipped. Within 2 weeks bearings started failing, we had to shut the mill down for about 24 hours for bearing replacements. Do the math: 400 ton per day pulp mill, over $1000 per ton lost production. Shippers/riggers learned an expensive lesson.

Run padded slings under the bed for crane lift, use padded fork lift tongs for a forklift pick.

And don't even think about running a tie down strap around the chuck or spindle when a lathe is loaded on a truck for transport.
 
I personnally would not consider lifting by the chuck - on a colchester 15 x 50 as I have, the Gamet bearings are spring loaded for preload and applying a load high enough to lift the lathe is almost surely going to shift the bearings out of their normal load range due to the springs compressing. No way would I take a chance on damaging them (the rollers are hollow for cooling), especially since a large hole for a lifting eye is provided in the center of the bed (which my lathe even came equipped with. :D

In lieu of that lifting eye, I would use HD nylon lifting straps threaded around the reinforcing webs in the middle of the bed - this avoids possibly putting high pressures on the feed or other shafts running down the front of the bed.

On my SAG 12, I used automotive carrier straps around the bottom of the heavy cast iron base:

P3060020.jpg


The straps were clipped to the H-beam of a gantry crane and the the one at the headstock end prvented the load from tipping to the side. In this case I only had to lift it a couple of inches - for higher lifts I would employ a third strap wrapped around the top of the hs to prevent tipping.
 
I've seen used machinery dealers that have been in business 50 years lift lathes by the spindle. Since they stand behind the condition of the machine they sell you they must know something after the thousands of lifts they've done that way. How many have we lifted and then guarenteed their condition? Me I think I know the answer. Experience beats armchair experts every time.
 
Be it right or be it wrong, why take a chance of doing damage to the machine. Lifting by the spindle is quick and easy, but if there is damage you have no one to blame but yourself. Rig it properly and sleep well afterwards. :codger:
 
Be it right or be it wrong, why take a chance of doing damage to the machine. Lifting by the spindle is quick and easy, but if there is damage you have no one to blame but yourself. Rig it properly and sleep well afterwards. :codger:

My thoughts exactly. If lifting by the chuck was the only option I might consider it as a last resort but I do believe there are better ways. There's nothing difficult about running straps and lifting by the bed...
 
I am not going to presume to know the answer, especially a general one for all lathes. My view is that there may or may not be a possibility of damaging the bearings. If you lift some other strong spot, the risk is zero. Zero against some undetermined, possibly small, risk still wins.

Bill
 
Me I think I know the answer. Experience beats armchair experts every time.

What's the consequence if the armchair experts are wrong and what's the consequence if you are wrong.

Does the manufacturers' manual of your machine show/recommend lifting by the spindle. If not don't do it, simple.

Phil:)
 
I used to work for a dealer and we had volumes of manuals from the machine tool manufactures and most of them showed diagrams of how to rig the machines and for the lathes many showed a sling around the spindle. I thought this was insane but I was shown the diagrams and figured they wouldnt tell you to do it if it was dangerous. I witnessed a 20x80 inch goodway get picked up by the spindle with the bed sticking out in front no other straps just hanging by the spindle with the headstock against the fork lift. I thought for sure it was a goner. I throughly checked it out after the incedent, no obvious damage. Six years later I am at an auction and I see the same lathe I ask the current owner how it runs and he says it has been great no problems, I ask some of the machinests who run it everyday and they say no problems super accurate. I think some of you dont realize how strong a lathe really is.
 
I've never lifted a lathe by its spindle, (with or without chuck interposed) and feel safe to say that I never will BUT as usual the finger-waving, overly cautious crowd must have a say, even some who get testy and and attempt to show they are in possession of vast knowledge of weight's and stresses with fancy engineerin' sounding verbiage. Know all them words m'self.

Check out the diameter of the spindle and compare that to the pin in a lifting clevis you'd feel safe joining the lifting straps with, 1/2"?, skeerdy cats maybe 3/4"? Depending on lathe weight of course but no matter the size/weight, the ratio of clevis pin to spindle would be somewhat proportional, for the reasonable.

Now, about "brineling" the bearing races? Not unless they are made of lead or you play bouncy yo-yo with the bridge crane! I have no qualms about raring back on a 4' spinning iron on my 17" lathe, it's leverage multiplied many times as it passes over the pivot pin an inch from the part dangled on a form screwed to the spindle, even if the form projects the cantilever 10 or 12" beyond the spindle nose. The puny and "static" (fancy engineerin' word) weight of the lathe doesn't approach that kind of "dynamic", (another'n) pressure on spindle or bearings when metal spinning.

.......all while, I hide behind them skeerdy cats and lift from the bed or lower, tieing against tilt:)

Bob
 
Just throwing out some observations and food for thought. You can and should do what you are comfortable with. Some lathes are more top heavy than others and can get away from you real easy. I would guess that more lathes are flipped over in lifting than those with spindle damage. I have sold every operating handle, handwheels, crosslide screws and associated castings on every lathe I have parted out. Never a spindle. Always the same story. It got away from me while picking up or moving. Yes some manufactures suggest how to pick up their machines. Some provide lifting holes for bars others plates to go under the bed with lifting eyes. Lacking a source of those recomendations you will have to decide what is the best way when you consider what can go wrong. Not all used machinery dealers are bad, just most of them.
 








 
Back
Top