Lathe Levelling And Other Lathe Issues

I suspect your lathe had a bad life for the first 16 years as you talked about in one of your earlier post. The movement you are seeing when traversing the carriage just a little is "slop" from wear of the saddle to the bed. The only way this condition can be corrected is by re-scraping the saddle to the bed. You can do all of the leveling you want but it won't fix this. Ken
 
If it is sitting on casters then they are adding to your issue.

The lathe bed may be "set" in a twist and when yiu adjust the casters they may not be solid enough due to cushion of the tires and play in the bearings.

You could swap the casters with adjustable feet.

If there is another area solid area near the casters to add a foot then the feet can be lowered to level and use then raised to move.

Pushing it just a bit past level then brining it back may help and if badly set you may need to go past level and let it stay there for a week then bring it back.
Sent from my SAMSUNG-SGH-I337Z using Tapatalk
 
Makes sense. It does not feel real solid as I can rock it back and forth like a cushy feeling. Like a little spring action without the spring, if that makes sense.
 
ddickey said:
Concerned about the amount of deviation from level I had to go. I guess as long as there is minimal twist it doesn't matter that they are not level to each other?
For headstock test how do you mount your bar. The Grizzly illustration looks like a chuck to me.
Click to expand...

If your turning tests are good I would say that it does not matter if you can confirm the ways level or not using a level.

The headstock alignment tests are numbers 5 and 6 in the Grizzly illustrations. The test bar is mounted in the spindle.
Compare those illustrations to numbers 14 and 15 which require a chuck.
 
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Sorry I'm not quite understanding. Between centers or is there MT5 test bars out there?
 
Not between centres, mounted in the spindle. I never felt the need to buy a precision test bar. My lathe was new and it works well so headstock alignment is not suspect.
 
ddickey,

I wouldn't waste time of money on a test bar in my opinion. All it's going to do is confuse you more. It will only tell you how much wear and tear there is in your machine's alignment. If you try to adjust your headstock to get it align with a worn bed, you will create more issues that you don't want. If you have a 4-jaw chuck, take a short piece of polished drill rod about 1" OD x 10-12" long. Indicate it in at the chuck and out at the end. Get it as close as you can to within .001". That will work as good as that $122 test bar will give you if not better. I know people say that not to use drill rod because it is not straight enough. I haven't yet bought a piece 1" diameter that wasn't straight. The problem with a store bought test bar, is that it registers with the taper on the ID of the spindle. I haven't yet found one that will run dead true end to end. Always out a tenth or two. The reason for the use of the drill rod is, it gives you an "quick" idea of what your alignment is within. Will also indicate how much wear there is in your 16 plus year old lathe has. The inspection record that Grizzy shows is only good as the machine leaves the factory, provided it passed all of the tests. Most of those tests are performed with special trueing fixtures that are mounted to the lathe spindle that allows the test bar to run dead true end to end. It's not necessarily a test bar stuck in the spindle or between centers.

I stick to my earlier statement of excessive wear in the saddle causing the indicator movement as shown in the earlier post. Yes, by all means, level the bed to remove any twist that may exists. This needs to be first item on the list to do in trouble shooting alignment issues. The two collar test in my opinion only checks alignment of the tailstock to the headstock. But you got to remember, when you have lathe that has wear and tear from use, these test are not going to allow you to improve accuracy to the machine. All it's going to do is indicate that there is wear in the machine. And from that, you improvise how to correct the wear or live with the wear.

Ken
 
The TS is not used in a two collar test.
I have a linear motion ground rod. I'll chuck it up and see what i get.
 
ddickey said:
The TS is not used in a two collar test. . . .
Click to expand...
That's how you check alignment of the tailstock to the headstock. And yes, if done properly, checks for alignment of the bed to the headstock, PROVIDED there is no wear in the bed. On a used lathe, you will have wear in the bed. And you don't use this method to realign the bed by twisting the bed into alignment. This is where the "Experts" are wrong in my book. It might be .001 worn, but the the most wear will be in the saddle of the carriage that rides on the ways of the bed. I'm sure your bed is harden, which is good, but the saddle ways are not harden and will wear over time. I'm guessing, your checking will find the alignment to be fairly close headstock to the bed. But it is hard to detect wear of the saddle to the bed other than the pictures you posted earlier of the movement of the dial indicator when moving the carriage back and forth.
 
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