Leveling the lathe - not sure if I'm "doing it right"

[jrgilman95]

Have you rotated and calibrated the level? Many do not like him but Adam Booth at ABOM79 has some good videos on setting up your level and leveling your lathe as well. There is also this video. Biggest thing is when leveling it should be level to itself not necessarily the world.

Yeah I did, the level is calibrated as best as I could get it. The bubble is only a smidge off.

I think I know what I'm doing wrong here though. I'm shimming the headstock side and it seems that you should avoid doing that at all costs unless you're trying to get rid of nod in the headstock. You should always shim the tailstock side first.

I'm starting from scratch tomorrow and going to try only putting shims on the tailstock side.

 

[verbotenwhisky]

Yeah I did, the level is calibrated as best as I could get it. The bubble is only a smidge off.

I think I know what I'm doing wrong here though. I'm shimming the headstock side and it seems that you should avoid doing that at all costs unless you're trying to get rid of nod in the headstock. You should always shim the tailstock side first.

I'm starting from scratch tomorrow and going to try only putting shims on the tailstock side.

It requires a great deal of patients, I chased mine on and off for several months. Keep in mind, during shipping and moving the bed can develop a slight twist and it takes time to get it to relax properly.

 

[benmychree]

A Starrett #98 level Is not sufficiently sensitive to do final leveling on a lathe bed; its sensitivity is only .005 per foot, not the generally accepted sensitivity of .0005 per foot (or better).

 

[cooper1203]

Your best off putting your level on the ways rather than the carriage as the carriage is shimmed its self i believe. have you got a 10ths micrometer or are you working to the nearest thou.

 

[jrgilman95]

A Starrett #98 level Is not sufficiently sensitive to do final leveling on a lathe bed; its sensitivity is only .005 per foot, not the generally accepted sensitivity of .0005 per foot (or better).

I mostly used the Starrett #98 to get me in the right ballpark and then am measuring the taper on the test bar after each shimming.

Your best off putting your level on the ways rather than the carriage as the carriage is shimmed its self i believe. have you got a 10ths micrometer or are you working to the nearest thou.

I originally used the ways with some parallels to get it close enough, but was using the carriage as a quick way to see if I was retwisting the bed. I think I may just be overthinking this slightly.

Yep, using a 10ths mic here. I think my issue was that I was shimming the headstock side which I learned is basically a last resort - going to shim only the tailstock side when I try again here soon.

 

[verbotenwhisky]

I mostly used the Starrett #98 to get me in the right ballpark and then am measuring the taper on the test bar after each shimming.

I originally used the ways with some parallels to get it close enough, but was using the carriage as a quick way to see if I was retwisting the bed. I think I may just be overthinking this slightly.

Yep, using a 10ths mic here. I think my issue was that I was shimming the headstock side which I learned is basically a last resort - going to shim only the tailstock side when I try again here soon.

You might consider one of these. Accusize Industrial Tools 8'' Master Precision Level in Fitted Box, Accuracy: 0.0002''/10'', S908-C685. For leveling you want to use these on your ways, putting them on the carriage will only compound any issues, for accuracy you setup from the bottom up, one step at a time. if your carriage has issues you'll not know it if you are using it as part of the procedure. First level the bed ensuring you have any twist out of it, then check the rest of the lath moving upward. The problem with a test bar if you are not certain about the rest of the machine is it will show an error if your head isn't aligned properly, you must first level the bed then use it as a reference surface for everything above it. The level I listed is very sensitive and you will feel like you are chasing your tail at first but once you get it where you want it you'll feel good about the machine. Aim small miss small.​

 

[WobblyHand]

You might consider one of these. Accusize Industrial Tools 8'' Master Precision Level in Fitted Box, Accuracy: 0.0002''/10'', S908-C685. For leveling you want to use these on your ways, putting them on the carriage will only compound any issues, for accuracy you setup from the bottom up, one step at a time. if your carriage has issues you'll not know it if you are using it as part of the procedure. First level the bed ensuring you have any twist out of it, then check the rest of the lath moving upward. The problem with a test bar if you are not certain about the rest of the machine is it will show an error if your head isn't aligned properly, you must first level the bed then use it as a reference surface for everything above it. The level I listed is very sensitive and you will feel like you are chasing your tail at first but once you get it where you want it you'll feel good about the machine. Aim small miss small.​

He'll feel like he's chasing his tail just calibrating it! I had to make a three point stand for a small flat stone, just so I could find anything close to a level line. Yes there's always a line, but the angular zone is very very small. Once I found the line, and marked it with tape then the calibration was the usual tail chasing. Yeah that level is sensitive, I have one and it took me a few days to calibrate it. Once I discovered that the kitchen floor was measurably deviating under my weight, I found a technique to get it done. If I stepped within 2 feet of the kitchen counter, the level showed it! 3 feet was ok.

 

[verbotenwhisky]

He'll feel like he's chasing his tail just calibrating it! I had to make a three point stand for a small flat stone, just so I could find anything close to a level line. Yes there's always a line, but the angular zone is very very small. Once I found the line, and marked it with tape then the calibration was the usual tail chasing. Yeah that level is sensitive, I have one and it took me a few days to calibrate it. Once I discovered that the kitchen floor was measurably deviating under my weight, I found a technique to get it done. If I stepped within 2 feet of the kitchen counter, the level showed it! 3 feet was ok.

I was leveling my lathe and the wife was helping, I finally said it looks like we are about 0.0003 off now and she stood up and says how much is 0.0003? I gets my feeler gauge out, find the 0.001 tooth and said see this? if you could divide the thickness up into 10 pieces it would equal 3 of them over 10".... she told me my parents were not married in one word then called me a bunch of ugly names.....

 

[WobblyHand]

I was leveling my lathe and the wife was helping, I finally said it looks like we are about 0.0003 off now and she stood up and says how much is 0.0003? I gets my feeler gauge out, find the 0.001 tooth and said see this? if you could divide the thickness up into 10 pieces it would equal 3 of them over 10".... she told me my parents were not married in one word then called me a bunch of ugly names.....

"Normal" people just can't comprehend this stuff. It's such a small distance we are chasing, it's beyond their ability to fathom.

 

[RJSakowski]

I have a Grizzly G0602 which is similar to your lathe, at least in the bed design. You mention at several point about shimming under the foot. Are you adding shims between the lathe and the stand? I wouldn't add shims under the headstock. Removing twist in the bed is one of adjust the level of the tailstock to the headstock and everything can be accomplished by shims at the tailstock end. When you add shims under the tailstock to remove twist in the bed, you are also twisting the stand. Which twists more depends upon the relative rigidness of each. The manifestation of this is that you add the shims which may or may not correct the difference in level between the headstock and tailstock but the two collar test still shows a twist.

Here is a post I did about my adventures with lathe leveling. https://www.hobby-machinist.com/threads/on-the-level-further-adventures-with-the-g0602.72338/ It will be worth your while to check out some of the threads concerning Rollie's Dad's Method. It is an alternative to the two collar test that doesn't involve making test cuts after each adjustment. An adaptation of it can be used to align the tailstock as well. Of course, the last word is the two collar test as it represents how the lathe is actually used. When you have made all your adjustments to your satisfaction run it for a final check.