Leveling a benchtop lathe 10x30

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Creativechipper

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Totally new to machining here.

Managed to get the lathe through the gravel driveway and in the house up on my work bench. No small feat here, felt like a pyramid builder.

I see now I am going to need to shim and level this thing. Looks like bring engine puller back in to lift up to get some feeler gauge pcs under it.

Knowing I am not the 1st to do this, I am asking for any tips and tricks.

What's next after leveling this?

Thanks, so much to do and learn and buy before my 1st cut..lol
 
You shouldn't need the engine hoist. Apry bar for a lever with a suitable fulcrum should do the trick. After leveling as best you can, you will want to check to see if it is turning a taper. There are two ways to do this.
The first is the two collar method which involves chucking up a stout bar. minimum 1" diameter and turning down a section near the chuck and one at the far end. This is usually done with the cross feed locked or at least unchanged. To facilitate this, the section between the two collars is usually undercut, so you have sort of a dumbbell shape. This allows you to make the two cuts on the test sections without touching the area between. On a properly aligned lathe, the two collars will have identical diameters.
The second is known as "Rollie's Dad's Method and involves making measurements of a round bar near the tailstock and at the far end. The bar should be round and ideally a uniform diameter although the latter isn't necessary, it just makes the calculations easier. The bar needen't be straight as the measurement method compensates for any runout.
The measurement technique consists of mounting a test indicator or dial indicator to the cross slide so that the indicator is in contact with the test area. The spindle is rotated and the maximum and minimum reads are recorded at each test area. The average of the two readings at each rest area will be identical in a properly aligned lathe.
Detailed descriptions of these methods are discussed elsewhere in the and other forums.
The RDM method can be used to check vertical alignment as well.
A final bit of alignment would be to align the tailstock center with a spindle mounted center.The two methods for checking taper can also be used for aligning the tailstock. The difference being that a spindle center, face plate, and lathe dog are used to drive the bar and the tailstock end has been drilled for the tailstock center. The bar is mounted between the two centers and either turned for the first methid or measured in the second method and the tailstock is adjusted for identical reads on either end.
 
Thank you so much for the detailed write up.

I skipped right past pry bar in my mind and raced towards an imaginary mini jack. Then the closest thing I have is the engine puller.

I have read about a machinist level vs a carpenters level. Any insight on what to do without one or is this basically a requirement?
 
Creativechipper said:
I have read about a machinist level vs a carpenters level. Any insight on what to do without one or is this basically a requirement?
Click to expand...

RJs post above states some of the methods to check the machine level. These can be use in lieu of a machinist level, just takes longer due to iterations of shimming, machining, checking measurements, etc.

An import machinist level is not too expensive and a good item to have in the shop.

8in machinist level at Shars
 
The Starrett 98 Series machinist level has a sensitivity of .005"/ft. Their 199 Series , .0005"/ft. The inspection grade Empire digital level claims .01º translates to .002"/ft. but whether this is truly achievable is questionable. Aside from sensitivity of the vial, the accuracy of the machined surface enters in. A carpenters level often has an extruded or, at best, milled surface.

A carpenter's level has about 10% of the sensitivity of the 98 Series level. A barely noticeable deflection of my carpenter's level puts my .0006"/ft. machinists level off scale.

Nonetheless, I would start by leveling the lathe. A lathe can have a twisted headstock and attempting to correct this by twisting the bed will result in a corkscrewed lathe. Truly, two wrongs don't make a right.

I would first level the lathe to the best of my ability. With care, even a carpenter's level should get you within .01"/ft. Next I would look at headstock alignment. I would do this by putting the faceplate on the spindle and sweeping across the surface. Alternatively, you can mount a carriage bolt to the faceplate at a suitable distance from the center. Rotate the faceplate so the bolt is to the front and horizontal with the spindle.
Mount a dial or rest indicator on the cross slide and zero out on the bolt head. Lock the carriage and recheck zero. Now, rotate the faceplate 180º so it is on the backside of the lathe and move the cross slide to intersect it. The reading on the indicator should be zero. (Note: there are some schools that maintain that a lathe should face a slightly concave surface, the reason being that such a surface won't rock when placed on a flat surface. I didn't go to that school) My G0602 has an adjustment for headstock alignment, others do not. I would first align my headstock for equal readings front and back.

There is the possibility that the cross slide ways aren't perpendicular to the bed ways. Checking that would require a known good square. Correcting a non square issue with the cross feed most likely would involve something like scraping the cross feed which is fairly advanced work.

Now, I would move on to the ways, checking for taper by either the two collar or the RDM method, and shimming as required. I would go back and check my faceplate measurements, readjust if necessary and recheck the ways.
 
Wow , this is really a delicate advanced measuring process, I never knew.

Funny in all the drop down option menus with goodies for the lathe, I never saw anything about tooling for leveling the lathe.

I definitely want to get this right and not have all my work be off center.

I will have to look up each procedure and buy some measuring devices, I lack most tools
 
It's amazing how little things can affect the work. I bought one of the cheaper machine levels on ebay, it gets the job done. Don't obsess over being "level", worry about the ends of the ways being the same. Get close enough to get repeatable readings on the level, then check both sides. There is a scan from a South Bend book that discusses how to complete the process with the 2 collar test. It even shows you which corners to adjust based on the measurements. The RDM method is also valuable. Spending time to get it right now will save you a lot of time later.
 
Thanks guys, it's all new and a lil strange to me but I love the challenge and love the feeling I get from making something good!!

Do I need other tools to get me going, I see machinist blocks and parallel bars and rounds, not real sure how these all co mingle?

Thanks again!! The more I learn, the more I learn I don't know..lol
 
Parallels, 123 blocks, etc. are more for the mill. They aren't useless on a lathe, but they aren't as important. Level it up, get a turning tool that fits and a drill chuck, and practice. You will learn what other things you need/want as you go. There are some threads around that give a good list of tooling to consider, but don't go too nuts at first. It's easy to buy a bunch of stuff you end up not using much. :)
 
Why do you believe that it is necessary to "level" such a small machine? Please explain this.
 
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