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Does anyone know the spindle run-out on a Southbend Heavy 10? What tolerance will it hold (assuming properly adjusted and in good working order).

TIA

They have a reputation of being one of the best- all other things being equal- short of a Monarch which will cost you 5 times as much. As long as the bearings in the head stock, and the quick change gears are in good shape you would have a hard time buying a bad one from what I know and the ones I've looked at. As usual with machine tools, the real issue is in tooling. Make sure it comes with or you have access to a good 3 jaw, 4 jaw, collet set, chuck set, cutters, center drills, boring bars, quick change tool holders, etc... to make your life easier ...
They do have a 1 3/8" spindle bore so you can do barrel work with them and most of the used ones come with a very heavy stand.

I wouldn't be surprised to hear they hold .0005" or better in good condition. My old Sheldon will with my good 4 jaw chuck on it, but not with the 3 jaw...

Spindle runout matters but is easy to measure and compensate for… You compensate for spindle runout with the 4-jaw or spider chuck…. but even if the spindle nose itself has zero runout, whatever chuck you put on it will have runout up the wazoo (technical term) unless you can dial it out. I use Set-Tru or Adjust-Tru type chucks for this reason when I’m “making parts”; I can dial my 10” Bison in at a given clamping diameter very quickly and the repeatability is excellent, way better than most would think a 3-jaw is capable of. Same with my 10” Buck 6-jaw, and the 6” Buck on my HLVH clone.

But for barrel work you want a 4-screw spider chuck with rounded brass or copper ends on the screws, and another spider chuck on the back end of the spindle so that you can adjust for both concentricity and axial alignment to the spindle CL. If you only use a 4-jaw, you can dial in the concentricity but it’s not going to be exactly longitudinally coaxial to the spindle CL unless you skim cut the chuck jaws themselves “in situ”with the chuck mounted on the spindle… and that can be tricky, depending on the chuck.

Measuring spindle nose runout is easy, although it can change with how warm the bearings and spindle are. Assessing the main ways, and the crossfeed and compound ways and leadscrews, is trickier. One way to get a read on the functional condition of the main ways is to cut a cylinder test and check for taper. Take a light roughing cut, then a light finish cut, using a sharp cutter on an unsupported bar of material sticking as far out of the chuck as you can get away with without it singing (chatter). You want a stout piece of material here. I have a left over piece of 1-5/8” T303 about a foot long I use for this, although I’m running the test using a live center to verify the tailstock is dead nuts for precise shaft works….. different test, same idea. Doing the test with the stock unsupported shows you if the ways are worn enough to drop the carriage relative to the CL of the work, which will change the resulting diameter of the test bar. Often lathe ways “dip” up close to the chuck due to normal wear. The difference in diameter is subtle, unless the ways are really worn, which is why you measure with a micrometer, not a caliper.

High quality floating reamer holders cure many ills……..

Thanks guys. Much appreciated. I'm a novice and looking to purchase a gunsmithing lathe and mill for tinkering in retirement.

How significant an issue is wearing of the bed ways? I've looked at a couple of lathes and the ads say "ways are noticeably worn". I've heard they can be resurfaced, but that sounds like alot of work and expense.

way wear can be scraped out if you know what your doing. But will cost a bunch. Might want to check out new Grizzley lathes

Don't settle on a 9".

Spindle bore hole is LIMITING factor.
Ask me how I know!

If you're buying used, check on parts availability before you buy. Don't settle for a small spindle bore.

Good shootin' -Al

I use my Webb 17x40 (Mori Seiki parts-compatible licensed clone) for my own gun stuff. The headstock is deeper than ideal but I’ve made tooling to get around that and it’s awesome in every other way. Overkill is great with machine tools. It’s almost 5000 lbs… anyway, why I say that is they do have full parts support. I crashed mine once and was really glad for the parts support.

A Heavy 10 is unlikely to have been used for production, which is one way you get bed wear. Another is exposure to abrasives. If previous owner(s) ever used it for polishing, or if it lived in a shop where grinding was also happening, then it’s likely abrasive particles got in between the ways and the carriage and that would do it. Also, I know SB (or at least their competitor Logan) sold some lathes where it was an option whether the ways were hardened. Don’t know if that’s true of the H10. Be extra diligent if the ways are soft.

Some bed wear won’t really matter for chambering; that’s all chuck and tailstock work there. Where bed wear gets you is if say you had to make a continuous, high-tolerance cut for 6” for some reason; if the ways are worn close to the chuck and part of that 6” cut takes place in the dip, you’ll see a difference in final diameter where the carriage rises up out of the dip. Visualize the cutter meeting the work, then dipping down a bit, to get a sense of why the diameter would change. But you won’t be doing that for gun work.

Honestly? I wouldn’t sweat bed wear within reason if your goal is to chamber your own rifles. Threading the barrel tenon is “seat of the pants” type precision; you aren’t measuring so much as cutting the threads until they have the perfect fit to the receiver threads. Nothing about machining the tenon area itself requires extreme precision. What does require extreme precision is the setup. That’s just you being finicky. If you use a good floating reamer holder it really does cure most small stuff- like a slight axial tilt relative to the spindle CL- by itself.

There are guys who hold the reamer solidly in an ER type chuck in the tailstock and then you do need the machine to really “right”. But that’s unusual and not necessarily better.

Scraping ways is a thing for sure but that’s advanced work and opens a can of worms… such as your tailstock not being the right height anymore…

A great place to ask about this is the Home Shop Machining forum as well as the Practical Machinist forum. On HSM especially they are very familiar with Heavy 10’s. You can find entire step by step procedures for evaluating them.

I bought a vintage South Bend H10 (1945) and got lucky on condition. I bought from a widow in Eloree SC back in 2012. Its been a great learning experience and would not trade a thing.
I have no trouble dialing barrels to within needle width repeatability using a .0001" test indicator.

Good info Jeff. You and Sheister make a lot of sense. Didn't know he was a machinist. Met him once and shot with him. Great guy that does excellent work with stocks and stuff. When I saw the OP, I just thought to myself runout should be easy to check with a dial indicator, then maybe correct for some issues with a 4 jaw chuck. The op should be able to tell right away how much runout it has by checking it, if at all possible. Maybe he's looking at it online where he can't put hands on it? Good stuff though guys.

I run a well worn and ancient South Bend 13 x 60, complete with babbitt bearings. When it's time to sneak up on a critical last pass dimension, I torque my bearing caps down very gingerly while its turning, stop, check with the old "Last Word" DTI.....and end up with no more than the width of the needle deflection. I can then run that tight setting, well lubricated, for up to 30 minutes without damage.
No I don't make parts for Boeing, I'm just making the point, you can run worn old heavy American iron and with a little patience, you can get quality results.
China imports are fine, Japs are great quality, everybody runs them that does any volume of work, but I wonder how many will still be going 80 years from now.

No less than Harry Pope used a Heavy Ten. I use a South Bend 13x60. Heavy Ten has the same spindle bore. It uses the same 5C collets which have made the 4-Jaw chuck nearly obsolete for me. I wouldn't trade my machine for 5 Grizzlies.

What brand/model floating reamer holder do y'all recommend? I have one that came from the gunsmith that I bought my 11" Logan lathe from 35 years ago and I cannot find any markings on it. I just wonder if there is better available since this one probably dates back to the 70's but you can bet Jack got it from Brownells.

I’ll look at mine. I can’t remember. I think it starts with a “J”, lol. It was $300+ about ten years ago if memory serves.

I’ll grab a pic of it and the spider chuck I made for my Webb as well as the spider chuck the PO of my old Logan made for it… he was a gunsmith.

Man this is getting me hot to do another build! DAMN you people! I have this wild hair idea… I bought a 7 SAUM M700 as a donor to build a 6.5 SAUM Mountain Rifle… this won’t be the year for a build, as I’m about to take off on a big adventure so I will be in a financial hole when I get back…. BUT… it occurred to me I could rechamber the 7 SAUM to 7 WSM (I have the reamer and gauges for that) and, if it shot ok, just lean on my pile of 7 WSM components (I have two) and shoot the living snot out of the thing! It would be kinda fun to have a rifle to just abuse with no guilt qualms. My two 7 WSM’s are well over 1k rounds each and have very visible throat erosion, but still shoot well, so they are no longer high-volume rifles, at least until I cut off a thread and rechamber….. I’m saving them for when it counts, like hunting.

Just watch, if I rechamber that factory 7 SAUM tube, it’ll shoot so good I won’t want to abuse it, haha… that’d be my luck. It’s a magnum profile barrel. Might shoot GREAT.

Speaking of getting things set up perfectly… if I do this, that 7 SAUM chamber is going to be the mutha of all pilots for the 7 WSM reamer; it’s going to follow it. If Remington cut the chamber with poor concentricity to the rifled bore, I don’t think I’ll be able to fix that. The new chamber will too. If anyone thinks otherwise I’d love to hear ideas. I could maybe prebore it just a little with my tiny solid carbide boring bar but there’s not a lot of difference between the diameter of the 7 SAUM and 7 WSM; the 7 WSM is bigger, but not massively so.

I looked online and found a picture of the Clymer and it is exactly the same.

Do you want one that goes in the tailstock or that uses a pusher? -Al

Hobby Machinist Forum is another good site to look at for input. Very friendly and knowledgeable people.

This is my reamer holder. I was right- starts with a J! The memory on this one, oy….



This is the spider chuck I made. It’s a direct mount to the A1-6 spindle. That pocket on the back is tapered.





This is how I did the spider screws. Drilled/tapped the end of an Allen bolt (they are hardened, be careful) and screwed a brass screw into it then rounded it.



THIS might be of interest for the OP, at least if the Heavy 10 has a threaded spindle nose. This is how the gunsmith who had my old Logan made his spider chuck. The knurled/threaded portion is just the thread-protector for a Hardinge indexer or the very common chinese copies.







I meant to grab a pic of the spider chuck I made for the back end of the spindle but forgot… tomorrow maybe.