Buying a used lathe a day's drive each way

[rhb]

Yes, cast iron creeps at room temperature. The world is rubber if you measure accurately and precisely enough. All of the first rank machinists will say the same. Listen to Robin, Tom and Dan.

I only mentioned it because of the bit about the floor moving. However, I learned this because a friend and I were discussing the subject and I did some research. I was quite gobsmacked by both the magnitude and the time constant.

Quite frankly, when I saw the graph from a Swedish government report I was stunned. I thought it was much shorter time constant and much less deformation. And the creep *never* stops. After about 5 hrs it becomes linear with time. though at almost negligible rate.

I've come to realize that the friction between me and a lot of the PM crowd is the result of my spending my career in an environment where *everyone* knew more than *everyone* else. No BS, they all had the credentials. So you learned to indicate your knowledge level in the nuances of how you phrased the question so that the other person could frame their reply properly.

Here the presumption seems to be that a new person is completely ignorant and, worse yet, stupid. Not how I view others. I assume infinite wisdom and grace until people prove otherwise.

Have Fun!
Reg

 

[Farmer Phil]

No BS, they all had the credentials.

Move to the education debate with the credentials. Someone they gave money to for the credential told them they were smart and they bought it. Pun intended.

 

[Garwood]

A lathe worth owning (hard ways) will have other major, notable, obvious problems if the ways are worn more than a couple thou.

That's the part you miss here. If it looks good, sounds good, feels good it's more than likely great shape if you know what you're looking at.

I bought a couple wreck machines starting out (at 23). Those machines would be obviously trashed to me from the pictures and not worth a look.

I have learned it's very, very well worth it to seek out machines from owners that took super care of them. People that you can trust and just take thier word it's good. It's neat to buy a machine and get it's entire history since new.

 

[Superbowl]

This entire thread cracks me up. How perfect of a used lathe does the OP expect for $4,000 dollars? Imagine calling a used car dealer about a 15 year old $4,000 car wanting the salesman to make measurements to ensure it drives like new.

 

[jccaclimber]

It seems like the OP wants to have his cake and eat it too. It should be cheap, but in great shape. This diamond in the rough should also be easy to find and available so they don’t need to go on a hunt. They don’t want to spend $500 to evaluate it, but want a machine tech to spend an hour or two for free.

We can debate dealer margins, but they would have to charge an awful lot more if they fully set up and inspected each machine. Of course then they’d charge $10k for the machine and you’d be doubly better off going private.

 

[kb0thn]

I don't know how big of lathe you are talking about ... but I know it takes a while to get a lathe off a pallet, untwisted, and "level". I've watched MTB techs do it and they spend a few hours getting a 10k lb CNC lathe dialed in. And they probably spend a few weeks of their life each year leveling machines, so I assume they are good or at least practiced at it.

Watching the same MTB techs commission a lathe, their main tool seems to be a micrometer. Cut a test bar until it cuts "perfectly" over the specified length.

 

[Overland]

It's all been said.
I think the OP has a totally unrealistic expectation.
Another example of someone who seeks input, but doesn't listen, or even want to accept the opinions he seeks.
We all need to move on, and wish him well, in his quest.
Oh well,
Bob

 

[Greg Menke]

I've done 3 long trips to look at lathes, one with an overnight. I brought the instruments to measure some key items for two of them so as to get a sense of condition. That long overnight was a bust because the shipping cost was just too much (though I still kinda wish I'd done it anyway)- it was a short 14" Pacemaker w 2 axis DRO. I ended up buying the other two machines, one was beat up and cheap the other was a bit more expensive but has ended up being a good machine. Yeah some $ spent driving around etc but pretty good fun all in- the road time is a great opportunity to catch up on the audiobooks.

If I was going to ask someone to go make measurements for me then I'd expect to pay them some kind of hourly rate- and they'd be independent ie not the salesman who would be selling me the machine.

money vs time is the basic equation as it seems to me, its possible to trade one for the other to some extent but ultimately you can't keep either.

 

[Joe Henderson]

Not really my fight but if you are that serious why not just go the other direction to Grizzly and look at a new machine. It's a hobby lathe right? If you are anal about a small lathe think Hardinge but that's going to be out of your price range. Just my thoughts on it.
If you are really serious about that machine then I'd go with a trailer ready to pick it up and move it myself. You can tell more about wear by running it in all speeds and checking the feed box. You can check the crossfeed and compound for wear on them. If everything works with no smoke and excessive noise and the lash isn't too bad then It's most likely good to go. Bed wear is pretty easy to spot and you don't need a level to do it. Is the spindle bore rusty? Stuff like that. Is it a threaded spindle or D1?

 

[Shipp]

This entire thread cracks me up. How perfect of a used lathe does the OP expect for $4,000 dollars? Imagine calling a used car dealer about a 15 year old $4,000 car wanting the salesman to make measurements to ensure it drives like new.

But with a used car I expect to be able to take it for a test drive, look under the hood, see how it feels and generally get an idea of what I'm looking at. What is a reasonable method to gather the same type of information on a lathe to get a general idea of what you're working with? I'm actually curious, I've not bought a lathe before

 

[beckerkumm]

A new Taiwan lathe that turns within tenths and is fairly lightly built costs at least in the 15K range now. A decent shape old lathe is in the 2-5K range. Condition tends to be a crap shoot so I always budget 1500-2000 for fixes, minimum, more if the motor is iffy. I like rare machines so my smart Brown 1024 was about 3K and turned out to have more wear than I liked and a motor problem but still turns within .001 and even a mediocre machinist like me figured out quickly how to cut that in half and with another minute and sandpaper, even less. Otherwise it is sweet because it is so well built. I also paid 3K for a CVA that turned out in better condition, turned within a few tenths over a reasonable range. That machine is now at a rebuilder to make it close to new as the machine is worth it. I'll probably have the cost of a new Taiwan lathe in it when done.

Long winded point is you might find a lathe for 4K that doesn't need much work or still turns in tenths but don't count on it. The benefit is in having a machine with mass and the bones that it can be made to be as good as you desire- with money. I have bought at least 50 used machines and maybe three came from owners who could really tell me exactly how well it worked and were truthful. I paid a premium in those cases. If you don't feel warm and fuzzy about the deal, look elsewhere. Stuff doesn't show up forever and then suddenly you find a machine that makes you feel excited. Your choice is a used risk of 2-5K plus more money to 15-20K and still some risk.

Dave

 

[Greg Menke]

But with a used car I expect to be able to take it for a test drive, look under the hood, see how it feels and generally get an idea of what I'm looking at. What is a reasonable method to gather the same type of information on a lathe to get a general idea of what you're working with? I'm actually curious, I've not bought a lathe before

With a mag base test indicator you can learn a lot about the general condition of a lathe- ie does the carriage deflect a little or a lot, is the tailstock quill close to level or way out, cross/compound shift on their ways a little or a lot, is there a litte or a lot of deflection in the spindle. None of those measurements require power. When digging a machine out of a basement only enough of the crap piled on it needs to be removed so you can traverse the carriage.

Then you work thru the controls to see about backlash, binding, examine visible gears and so on. You'll get snafu'ed with the deeper in issues- bearings, keys, bodged repairs regardless, the idea is to measure what you can, observe what you can.

If the machine is powered thats a help, but sometimes thats not possible.

 

[Shipp]

With a mag base test indicator you can learn a lot about the general condition of a lathe- ie does the carriage deflect a little or a lot, is the tailstock quill close to level or way out, cross/compound shift on their ways a little or a lot, is there a litte or a lot of deflection in the spindle. None of those measurements require power. When digging a machine out of a basement only enough of the crap piled on it needs to be removed so you can traverse the carriage.

Then you work thru the controls to see about backlash, binding, examine visible gears and so on. You'll get snafu'ed with the deeper in issues- bearings, keys, bodged repairs regardless, the idea is to measure what you can, observe what you can.

If the machine is powered thats a help, but sometimes thats not possible.

Thank you

 

[michiganbuck]

I find it can be difficult to test a lathe with a test indicator with a ball nose point, and think it is better to test with a dial indicator having a flat nose point squared up to the axis. That way the up and down riding on a diameter doesn't influence the reading.
Also turning a part to the same diameter at both ends can be misleading because there can be errors in the mid-section of the part turned.

Yes, one can cross-travel and strike a test indicator over/across the top of a test bar and see the up and down of the bed way travel... but how you hold the test bar changes the readings.

Many dealers don't want to make any promises about a used lathe and that is understandable.
My experience was with decent lathes that could run thousandths and tenths with using a slip of crocus cloth.

 

[michiganbuck]

A very nice-looking lathe might be a cream puff..Or if used as a grinder might be scrap.

MONARCH 14" X 30"TOOL ROOM LATHE - heavy equipment - by owner - sale

Monarch Tool Room Engine Lathe. 14" Swing, 30" Between Centers, 50" Bed, 1-1/4" Hole Through Spindle, 18-750RPM Spindle Speed, 14" 3-Jaw Chuck, Tailstock, Steady Rest, 240V 3 PH under power Price:...

detroit.craigslist.org

 

[Tyrone Shoelaces]

A few tips if you’re looking at a lathe or any other small machine tool and you can’t power it up. Do all the levers/handles have their original plastic ball handles ? Does the work light still work ? Does the coolant pump still work ? Is the machine still in it’s original paint ? Has the operator been using the end of the bed as an anvil ? Knocking drills out of drill sleeves by banging the drift down on bedways. If the answer to most of those is Yes - the machine as been looked after. No - and maybe the operator has neglected other things that aren’t visible.

Operator neglect or not is the difference between a well used but looked after machine and a semi wreck. If the machine has had one careful driver it should still be good. Beware of maintenance shop lathes. Lots of different operators, not all of them know what they’re doing.

Look at the front edge of the cross slide and the four way toolpost. Has it got lots of chuck rash ? All indications of a moron operator not looking what he was doing. What condition is the tray and backsplash ? Again if they’re damaged and and full of lumps and bumps it doesn’t augur well.

What are the oil levels like ? Pay extra attention to the oil in the apron. If you can take a bucket and a small funnel. Insist on draining the oil in the apron and see what comes out. Nobody should object if you promise to pour it back in again. If it’s mainly old coolant followed by some oil, you may have an expensive problem. Lots of my work involved repairing the gearing in lathe aprons ( and milling machine knees ) that had suffered coolant rot.

What’s the backlash like on the cross slide and compound. Half a turn and it’s well worn. Don’t just wind the handles, grip the tool post and give it a good shove,

Having said all that I’d never buy a machine that I could see ( and hear ) running.

Regards Tyrone.

 

[jim rozen]

1) a seller probably won't do any hand-holding like this.

2) a level or a test bar of any flavors won't help.

3) possibly ask for a video of the machine cutting under power.

4) just go there, with the sure and certain knowledge you'll either come home with a nice machine OR will have had an excellent road trip but this wasn't the lathe for you.

 

[rhb]

I'd like to thank the last few posters for offering practical comments. It is a welcome relief. Last night I went to bed intending to drop off PM.

I can't tell someone what insert to use for a particular alloy. I don't know that. But I have other skills which are highly relevant.

I ran what I came to call "the orphan home for lost problems" at multiple major oil companies during the course of my career. I got into that because I didn't care who or how the problem was solved. Just that the person who asked me got an answer. I'm very good at finding answers.

I'm a scientist, not an engineer, but I have a comprehensive understanding of the mechanics of materials, machining and manufacturing. I should hope that I have something to offer to the PM community. But perhaps not.

Reg

 

[beckerkumm]

Couple things to check if you can't do a lot of tests while running.

Take the headstock cover off. Engage the gears. Do they mesh well, do they look like they have been jammed and mucked on the edges. Do the drive dogs look abused ? Rounded corners, bronze slippers showing wear when they slide on the shaft ? Is the headstock splash oiled or are there lines and valves ?

Change some thread gears. You should feel the tumbler moving in and out and engaging all the gears on the rack.

Pull on the leadscrew to see if it has end play. Look at the center threads and compare with the ones at the ends. If you can see a difference, there is a lot.

Fingers and fingernails are very sensitive. Feel both sides of the Vee. If there is no ridge or very little, chances are the wear is light. If you feel a definite ridge, especially on the inside of the front Vee, you have enough wear to effect the turning. How much is unknown but you will have to compensate for it when using the machine.

Put a dial on the tailstock quill and tighten the lock. If the quill moves more than a few tenths there is wear which generally means the machine has been used heavily.

Crossfeed screws will show wear but usually are tight at the extremes and loose in the center. That difference makes dialing them in a compromise and again shows the machine had use and the oiling of the screw and nut wasn't done as much as it should be. New screws or nuts can be made or bought so not a deal breaker but extra work.

Run the apron back and forth. If you see oil, there is likely less wear than if they remain dry. Apron oiling systems seem to be a weak link on many machines. Oil on the ways makes for a happy day.

Look at the motor and electrics. Check the motor to see the frame size and if there is ample room. Replacing common frame size motors can be done cheaply if you watch. I watch for Vector duty Baldor, Marathon, or lincoln motors and find NOS surprisingly cheap. I just got a 10 hp Marathon Black Max NOS for $325 delivered and stock up on 3-5 hp motors when deals show up. Odd motor sizes or Metric frame motors will be harder to source. Extra room is good as sometimes newer motors have the electrical box in a different location than old motors although the frames tend to be smaller now. New machines are notorious for jamming lots of windings into small frames. Old motors are the opposite which makes them easier to deal with- other than lifting.

As was mentioned earlier, look for signs that coolant was used a lot. Coolant in the gearbox or apron is usually a deal breaker unless you can verify there is no damage.

If the machine has original paint, look for evidence on the bolts and screws that parts have been gone into. On my machines, almost every thing I open up that has been opened before has a crap repair. My experience with machinists doing repairs is that quick is better than permanent.

You will find some issues in any machine. You need to decide what is critical and what you can live with or fix, but judging from all the posts regarding new machines, you will have some issues there too.

Dave

 

[Ultradog MN]

Two years ago when I was looking to upgrade to a better lathe I made the 10 hour drive with my trailer from the Twin Cities to Cincinnati. I got there and despite a couple hours of conversing with the seller before I left home, I did not like/want the lathe. I turned around and drove the 10 hours back home.
It was a tough decision to come home empty handed but I made the right choice.
As it turned out, a couple of months later I found the lathe I wanted - a hundred miles from home. Even adding the cost for fuel going on that wild goose chase to the price I paid for my lathe I still got a great deal. All I can say is be patient and keep searching.