What's new
What's new

lathe leveling

coyotebgone

Aluminum
Joined
Dec 20, 2009
Location
bainbridge ga
I am looking for some tutorial or help on leveling a lathe (14 x 40 logan). I have a machinist level but am a "TOTAL" amateur.

I really appreciate all yalls help.

Herschell
 
Well, while we're waiting on more skilled help, here's some things to ponder.

First, it's really not rocket science, but little details are a big deal.

Make sure you have a way to adjust the lathe. Do you have leveling feet on it already? Make sure they're loose and easy to adjust.

The level needs to sit at a good place, and sit there correctly. Best to find a surface that isn't worn and is representative of the ways. The little pad the tailstock sits on works well, not sure if it's big enough or not. Then you need to sit it traversely. Might need a couple accurate gage blocks or parallels to hold the level above the vees and be indicated off the level pads for the carriage and tailstock. Doubtful the top of the vees is a good location.

Also, make sure the bottom of the level, and where it's going to sit, is nice and flat. Debur the area with a fine stone or something.

So then, just go about leveling. It's a back and forth procedure. Level it long ways, then across.... lather rinse repeat. Make small adjustments with the feet, and wait for the bubble to settle out.

Oh, make sure the level is calibrated, it should read the same no matter the orientation. Flip it end for end to verify.

These levels can be accurate enough to show movement based on where you stand, so I'd stand in the same location for each measurement, otherwise you'll chase your tail around and around.

Hope this helps a little. Just give it a shot, nice thing is that you can't really mess anything up. Be sure and check it again in a couple days, see if things have settled out. Check the lathe traversely along the ways, look for twist in them. You'll likely be able to take that out with proper leveling.

Tools
 
Proper lathe bed leveling is extremely important for accurate,
repeatable work. Many people don't understand what 'level' means in
this context. The purpose of leveling a lathe is to ensure that both
ways run as perfectly parallel as possible with each other in the
vertical plane, and has little to do with 'level' with respect to
gravity. If the front or back way is slightly higher or lower than
the other one, it doesn't matter as long as the deviation is constant
from one end of the machine to the other. Therefore a lathe on a ship
can roll and pitch around all day and still be level with regards to
machine work.

The weight of almost any lathe is sufficient to twist the ways a
small amount when it is set on the floor because the base/pedestal
etc is not precisely finished and the floor is not likely to be
perfectly flat. A sensitive level capable of resolving .0005" over 8
or 10 inches (or better) must be used. A carpenter's level will not
work.

If you do all of your work within a very few inches of the headstock,
minor leveling issues may not show up. On the other hand, if you
turn longer pieces you won't be able to find the true center point
for the tailstock set-over because that point will vary depending on
the carriage position along the twisted ways. Errors related to bed
twist are affected by the height of the tool holder stack above the
bed, the distance between the front and back ways and the amount the
bed is out of level.

Many hours of frustration and spoiled work can be avoided by spending
the time required to properly level your machine.
 
I wouldn't worry much about levelling the long-way. Unless its so far out that the carriage rolls away on it's own, that dimension won't matter except for where liquids pool in the chip pan. Also, I would keep the level orientation consistant, that is, keep the same end toward you throughout the process. You're looking for identical indications along the bed, not necessarily a "zero" reading. Swapping ends on the level is one way of determining whether it has a true zero, but it will screw things up if it isn't perfect.

You need to let the temperature stabilize in your shop for as long as possible before leveling, and expect things to shift seasonally or more often. It just isn't going to stay 'level' for any length of time.
 
I am under the impression that the machine should be as level as possible for two reasons. The first is how the accuracy of the produced work will be affected if the previously mentioned twist of the bed is not minimized and second is for long life of the machine tool itself. On some lathes only a splash lube system for gears and bearings in used. The lubricating oil to important parts such as spindle bearings are drip fed from a trough above them after it is thrown up from below, if the tail end is to high the right bearing may get no oil while the left gets all of it. I don't know what affects gravity will have on slideing members such as the carriage or cross slide if they are too far out of level but I think one side of a screw would have to wear more than the other if it was forced into a constant up hill battle. I may be over analizing the situation but the question was raised. Hope this helps.
Dan
 
As others have mentioned above...

But... some lathes do need to be level (not just "true ways") -mine pressure feeds oil to the major headstock components, drains down to a collector plate with 4 drip holes about 6 inches apart, down though the QC and then down to the main drive where it's all pumped back up to the headstock. If the lathe is 1/2 inch out of level, some parts of the QC do not get lubricated.

After the lathe is leveled, cut a long test bar. If it's not to your liking, you'll have to figure out if the lathe is not really level, the bar is "bending" under tool pressure, or some component of the lathe is now affecting the test. You can spend a lot of time chasing ghosts.

Oh.. I spent hours on morning leveling a lathe. Then the low winter sun came in though the window shining on one side of the lathe, and when I came back from lunch, the bubble had moved to the other end. By dinner, it was back to the middle. I've now decided to not check mine often... I know it will be out. If I need to do something critical, then I'll break out one of my levels. I have two levels - 0.0001 in 10 inches, and 0.001 in 8. I like the latter better ;)
 
Many people don't understand what 'level' means in this context.
Obviously.

The reason for "leveling" a lathe is to put it in the same position as it was at the factory, so all stresses and bearings match the original conditions when it was trued.

This is most easily accomplished by using the earth's center as a reference, as shown by a level.

- Leigh
 
Do a search for "lathe leveling". The subject has been discussed here lots of times.

If your lathe has V-ways get some 1-2-3 blocks because your level needs to span flat-to-flat across the ways. The very top of the Vees is not a reliable reference surface.

-DU-
 
I'd kind of go with Gordons advice. I have only leveled a few machines. Two small CNC lathes and a Monarch 10 EE. The Monarch is a three point leveling bed, and the CNC lathes have 4. The CNC lathes came with their own leveling screws and steel pads. The first time was a pain, back and forth, bach and forth. I also have a Master Machine level. It is not a Starret, but made in eastern Europe.
I did rough in the Monarch with a 2 ft carpenters level. I used some block I ground on the two flat ways. If you have 'V' ways, then you might need to use 'V' blocks. I used UniSorb leveling pads on the Monarch. They came with the machine. There is a post in the Monarch section, with what I did. Others there use Vlier pads.
I do think leveling is important for accuracy and to reduce machine wear. Basically, you want untwisted ways. But leveling is a reference point to achieve this. Also, google Rollies method. I haven't done it, nor do I completely understand it. Still, others prefer it.
I might use your machinist level, in between the carpenters level, and if you can't get or borrow a Master level anytime soon.

Tom
 
If you don't have a manual---try and find one and follow the basic instructions it gives for leveling that particular lathe. The lathe's construction may have one side higher or lower than the other. My Leblond does and brings that to your attention when leveling it.
 
Old thread but a new tip. My lathe uses jacking bolts at each corner. Too tall, inside a pocket, to use a socket so a ratcheting box wrench is needed. I should have removed the bolts and soldered or welded a washer under the head. They are metric so I was not going to find a flange head bolt to fit.
That way the wrench can not fall down off the head requiring one to keep it up and down and turn it all at once. Probably most useful for the rear bolts.
BilLD
 








 
Back
Top