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Measuring runout on a lathe is a royal pain to do correctly. Simply measuring the spindle with an indicator is not the best way to do it.
Test bars and plates are expensive but they are what should be used to measure the runout on a machine among other things. An old toolmake I know has a couple of test plates that ride in the spindle of different lathes. Precision ground to near zero run out. He can place this plate in your spindle and measure the runout at a 10" diameter magnifying the error.
The other thing is to put a load on the spindle and see if the bearing are moving.

Now here's the deal. Most engine lathes are rated at .0007 TIR spindle run out or less. most tool room lathes are rated at .0001 TIR. At the spindle nose. Then there is the difference between id an od and at 12" out with a test bar. Parallelism with the carriage movement both top and side, same for the compound movement. Cam action of the spindle. where the spindle axis changes due to the forces applied to it by the running gears. Which is why belt drive machine are more accurate in spindle run out then geared head machines. You have removed one influencing force from the spindle.

That said, that is if your indicator can read .0001" TIR as most won't. Pull out the cert on accuracy and repeatability. it will shock you.

Thing is with a four jaw chuck your spindle could be out .005" and you could still dial it in to near perfect concentricity.

Or use an adjustable three jaw.

KLS good post

Either way it needs to be an independent chuck not a scroll chuck. Or if it is a scroll chuck it has to be a set through scroll chuck

I'm just past learning that there is no such thing as perfectly centered when you have good gauges, so what you are saying is definitely resonating

Thanks.

WAY beyond my ken to measure all that stuff. When I mention measuring runout in the future I'll be more specific that I'm just talking a no-load measurement right at the spindle with a .0001" indicator. I am pretty careful about it; I'll measure different parts of the nose taper, plunge or retract the indicator more to make sure I'm not in a funky spot in it's travel, and so on. But your points are very good ones.

Metrology is fascinating stuff. It'd be fun to take some classes. I saw there's a scraping/metrology class happening in Seattle soon.

Practically speaking, I get myself tied in knots trying to think it through, but, with a 4-jaw dialing out spindle runout it seems that you'd only be able to get it true to one spot in Z. For any machining operation requiring a cut parallel to the spindle (like chambering) as you moved away from the spot you'd dialed in, your error increases. Which would be less and less true, the less runout there was to begin with, so, less runout is ALWAYS better. No?

Alright so who makes a lathe 1.25 or more through the spindle at 16" or less??

Hey spotshooter, you made me curious so I bopped over to Griz just now... the 3-phase lathe that costs twice as much is a 16x40 and also weighs twice as much as the 14x40. Now it makes sense.

I was planning on buying an 0509G myself so I'm not anti-Grizzly by any stretch. With some crucial help from Dennis I found an arguably superior machine for half the money and with a nudge from him... a dope-slap as it were, grin... I snagged it a couple months ago.

Ok, I'll bite - what did you end up getting Jeff ?

One of these, except half that money and with more tooling. It's a South Korean licensed clone of a Mori Seiki. Super beefy- for perspective, it's almost a full ton heavier than the bigger Grizzly, the 16x40 0509G. Weight is good!

http://item.mobileweb.ebay.com/viewitem?itemId=190717399984

The tooling included several good chucks... 9-10 Aloris toolholders... a custom oversize steady rest.... the most intriguing is a 10" 6-jaw Buck chuck that they threw in towards the end of the deal. Those things are well over $2k new. I haven't used it yet- needs a backplate. It has a nice 10" Bison Set-Tru that I use all the time, and a 12" 4-jaw I've mounted to practice dialing in barrels with. I'm buying a chunk of steel to make a spider chuck to use instead. That'll be interesting- basically machining an A1-6 backplate, complete with a subtle taper to mate with the spindle nose. But, that 12" 4-jaw is a b!tch to wrestle on and off and I'm not getting any younger.

Deep headstock on these machines. I made a tool that reaches in from the outboard side to engage a muzzle and then allow precise adjustment.

Well I run a 1945 14 1/2 x 7 South Bend it only has an 1 1/8 thru hole. Of course it is belt drive the best thing I ever did was buy a South Bend belt that eliminated the seam. My spindle doesn't show any run out but I don't have a .0001 indicator. I use a 4 jaw chuck 99.9% of time. For barrels that won't fit in thru hole I thread and chamber from centers using a face plate and turning dog. I use a floating reamer holder to handle any small amount of run out that might show up. The one thing I learned was that these engine lathes have to be dead level in all directions or spindle run out will be the least of your worries. And level needs to be checked often especially on a new machine and one that has been recently moved as they tend to unwind and settle into there new position. That being said I don't build bench rest rifles but the vast majority of my rifles will shoot 3 shot clover leafs. Most barrels won't go completely thru my thru hole so a spider won't help. So I have built a set of tapers out of 1 1/8 round stock that I use to center the barrels in the thru hole. There are always several ways to skin a cat so use some common sense and logic to figure out your machining needs.

South bend!! It's called a heavy 10 or a 10L i had one sold it off for the machine I have now.

Not exactly true. In chambering we not only want to be as accurate as we can in concentricity but also in cylindricity. Your observation of the error getting worse the further from the spindle nose is an example of being out of cylindricity.
See if you had a test bar in the spindle and it read +.0005" at some fixed point on the diameter then dialed to the end of the bar and got the exact same runout at the exact same position that would be an error of concentricity and a perfect reading of cylindricity.

Please don't take these comments as a high and mighty attitude (and not saying your did either) I was just tasked on more then one occasion to verify a test report from a machine supplier. I learned a lot from that old toolmaker. He taught me how to scrape too. So I've had first hand experience pulling out my hair trying to eliminate all the variables to be able to confirm a number.
It's a royal PITA and it enough to make you go bald and have an ulcer all at once.

Jeff O
One of the shops I worked at had that exact machine. Renamed a Hawachieon or something close. It was a Korean import. Damn near as good as the Mori only half the cost. You have my dream machine. Damn good score.

Wtroger. CORRECT!! I have a .0005" over 12" precision machine level just for double checking my machines. And you are correct too in that if it ain't level run is nothing. How about turning a coke bottle shaped part. all because your bed is all over the place. Dead level and double check it every few months after a new move. Once a year there after.

Thanks! Yes, it is rather awesome. I had to go get it- 8 hours up, 12 hours back in the driving rain- which probably took years off my life, but it was worth it. They didn't know what they had. They mis-spelled Webb as "Web" on the Craigslist ad, which I suspect kept the dealers from noticing it long enough for me to get it.

I couldn't have done it without Dennis. He edumcated me on lathes in general, gave me the heads-up on these specific machines, and then gave me a good prod forward after this one came up and I sent him a link to it. Big time good guy!

I just grabbed the first link I saw in the post up above.... just noticed the pictures on that auction are terrible, all distorted. Here's a pic of mine, running temporarilly off the 3 HP VFD from my mill:

Just get it good and level. I'd change the spindle oil if it's remotely discolored. Buy some good way lube and never have to buy another machine again.
If you ever go to sell it CALL ME I'll make the trip & pay cash. I don't care if it's ten years from now.

FYI Webb machinery were the one that founded this project i.e. the Mori copy. What they did was buy a used Mori and shipped it to Korea and told them make a exact duplicate. They did No the one interesting thing is these machines were marketed under a few different names. Webb, Hwacheon (sometimes shortened to Wacheon) and Cadillac . The machine we had was a Hwacheon branded machine close to a 15X40 size. Damn heavy duty and very precise. Our top toolmaker checked this one out with me under his wing. I remember the spindle being out by quite a bit for run out. I believe it was .002" at the nose. Thing was you put it in a mid range speed, let it run for an hour to warm up and it settled right in at .0005" TIR Very weird but as long as you knew about it, it was not an issue.
BTW those machines as you've seen sell used in good condition for $8K-$12K
New starting at $16K and the original Mori sold new in 1995 for $20K we got our copy for $12K with a full tooling package.

This is my old machine



Sold it for $1400 only paid $600 for it but it left with a bunch of tooling.

This is the new machine. this was taken as soon as it was dropped in the garage. That mother was heavy


I also scored this surface grinder from a Aerospace shop in town. This went to salvage and I picked it up for $300 with the mag chuck and a spare arbor

All this guy needed was some cleaning up.

That Maxturn looks like it'd be heavy! 14x40? How deep through the headstock?

We've kinda blown up Spotshooter's thread here... sorry SS! Maybe it makes the anticipation even sweeter?

Wacheon still makes these manual lathes. Now they push $30k! Parts availability was a big factor for me, though obviously I hope to never need it. I did make my own parts to fix the compound gib adjustment setup. It'd been Bubba'd beyond comprehension.

My Webb is way too deep through the headstock for a standard outboard spider. I asked some questions on the PM forum about tooling for chambering through a long headstock, and ended up inspired to make a tool based loosely off of one the late Shelly Davidson used on his Victor. First step was to put a spider on the outboard end of the spindle- not to hold the barrel, but to hold the tool. In a perfect world it'd have been a press fit on the spindle OD. In my world I ended up needing to mount it via two rows of brass-tipped jackscrews. That was a royal pain to get it running true. Not that it really needed to be, but... you know...

Here it is shown without the 4 exterior jackscrews.



The purpose of it is to lock down this tool, on the bottom shelf. It has a solid steel center shaft, which pivots on a circular bronze bushing I made on the Logan (it has a ball turner). That keeps the play to a bare minimum while allowing the shaft to pivot. It has two bushings on the OD that fit very snugly inside the spindle ID. There's a bronze center on the right end of the steel shaft that engages a barrel muzzle deep in the spindle. You adjust with the black jackscrews. The silver ones just lock things down extra-tight once it's where you want it. The part on the left with the thumbscrews is a centering bushing.



Here it is installed on the lathe:




A lot of work, but I want to be able to work through the headstock on this machine. The tool works GREAT! I can easily and predictably and very precisely adjust the position of the muzzle, then lock it down tight.

Of course,, this could also be accomplished by sleeving the barrel to make it longer and just using my outboard spider. That didn't occur to me until after I'd built this tool. I'm not the brightest candle on the cake.

Again with apologies to SS.... check THIS baby out. Very rare bird. It's a Dutch Hembrug AI.... got to see this over Xmas.... it belongs to my stepdad, who is of Dutch heritage and is an engineer with a fabrication shop. It'll be mine if I want it when he retires. It's roughly 17x60", 6500 lbs, and they are supposedly Swiss-built works of industrial art; very precise. Also a complete orphan machine.





I don't know if I'll have work warranting owning that machine or not. I think in that size range, I'd rather have one of the 17x60 or (!) 20x80 Webb/Wacheon machines. OTOH, I could hardly stand by and let such a rare and high quality machine get sold off for scrap or something!!

Actually now that I look at the numbers and do the math my Takasawa Max turn is close to a 16X30 it's 400mmX800mm with a a 5HP motor.
It's 20 or 22" of head stock then add the chuck. Your little gizmo there give me an Idea. I think I'me going to steel that design and make me a copy of that.
I'd rather have one tool that can do multiple things then sleeve each and ever barrel that comes in.