Monarch 10ee

I meant to say headstock not tailstock. I reversed the piece and same thing: dead on until about three inches from the headstock then dips 3-4 thousands. I checked the tailstock again with my laser. It is dead on.

I think a lot of work was done very close to the headstock because it came with a complete set of collets many of which have "bites" on their noses. And the drawbar handwheel is worn smooth.

I'll closely examine the ways in front of the headstock.
 
I meant to say headstock not tailstock. I reversed the piece and same thing: dead on until about three inches from the headstock then dips 3-4 thousands. I checked the tailstock again with my laser. It is dead on.

I think a lot of work was done very close to the headstock because it came with a complete set of collets many of which have "bites" on their noses. And the drawbar handwheel is worn smooth.

I'll closely examine the ways in front of the headstock.
I want to learn. Unless you are using a Laser Interferometer, how can you claim it’s dead on?...Dave
 
try turning a small diameter like 3/8" between centers, maybe 4 to 6 inches long, with very sharp tool see how that correlates to the larger stock you turned.
 
Have you checked the run-out/TIR of the collet/chuck. Have you tried a different chuck and do you get the same thing? I often see collet holders and standard scroll chucks with this kind of run-out, sometimes more.
 
I used one of those laser edge finders. It fits into a 3/8 collet. and shoots a beam at the live center.

I have a 12" piece of 5/8" ground and polished stock. I'll chuck that and see how it clocks.

The ways seem OK no noticeable dings.
 
laser edge finder is not going to get job done IMHO. Use tried and tested methods. center drill shaft both ends turn between centers, and see what happens, adjust tailstock and see if you can get accurate results. Might try Rolies Dad's method. Lots of methods will work, the laser edge finder might get you in neighborhood for a wood lathe but for a 10ee or a HF mini lathe, not!
 
Maybe I'll Sh-- can it. Probably should, I've always been suspicious of it

OK here are the results of the test with the 5/8 ground bar: spindle runout 0,00, chuck .002, work at chuck, .003, work at 8.5" .004.
 
Its really tough to realize your new gem is not perfect. But until you go about it scientifically you are basically throwing darts at the wall hoping for a bullseye. So level the lathe in both axis, let it calm down for a couple days or so, redo if necessary. You need a .005" level at the least and preferably a .0005" level. Then you need to center drill a shaft on both ends, turn between centers where the headstock center is trued by turning. then turn the shaft and see where you are. Using a 40 year old chuck to hold one end or using a clapped out collet chuck is not going to get you where you want to go. You also need to adjust those saddle bearings on the carriage. Like I said before and on the phone, the list of posts at PM is a huge resource, read thru all of em, might take a couple days, but compared to giving up on this machine it will be time well spent. Even a worn EE can produce great work, but you need to spend the time dialing it in, figuring out where the problems are and then figuring out how to work around them. Lots of issues affect end result, what is your backlash on cross slide, compound? Do you have a lot of overhang on compound, if so you could have flex, especially if your screw has horrendous backlash. Are you using a good tool post or some POS flimsy thing. If those carriage bearings are not adjusted correctly you are pissing in the wind. I don't mean to sound harsh, but you got yourself into this buying a freshly painted machine you had never seen in person or used in trial , its incumbent upon you to make the effort to sort it out, If you come back for further input you would be wise to list a detailed list of what your last effort was and how it compared to past results. Go about it scientifically, lay out all the facts and details.

michael
 
So most of the run-out is the chuck, and then if you are using 5C collet that can add 1/2 to 1 thousandth, ther is also collet to collet variation. You might be able to tweak the chuck a bit, but even the best adjustable (set-tru) chucks can spec up to 0.004". You will also have a small amount of deflection of the bar at 8.5" and ground bar can be vary a 1/2 thousandth. When checking the TIR at different point along the rod, I look at the +/- swing around 0, so if +/-.001 at the chuck, I would expect +/- 0.002 at 8.5". If the swing is more in one direction then the piece may be skewed in the chuck or an alignment issue. Adding it all up, it is pretty darn good. I think you are getting a little tapering at the chuck vs. the tailstock because of the TIR, but there are many factors. If you have a 4J independent you could zero out the TIR at the chuck. Laser alignment in this setting is not a good idea.
 
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