When I first set up my lathe, on a way-too-flexible floor, it took me
a long time to get it dialed in. Part of that was the floor's fault,
part was that I didn't have much clue what I was doing. I did
finally get the lathe lined up, but I have no idea how. I seem to
remember that it involved about a million cut-and-try experiments,
some intense profanity, and luck.
Time to do it again, this time on -- hallelujah! -- a concrete
floor. I recall from way back that some people were fans of Rollie's
Dad's method of lining up a lathe. I've just looked it up and it
seems sane. (See
What say you? Is this a viable way to set things up? Any problems
with it? 'Cause it sure looks simpler than cutting a thousand test
For normal usage, I would not use, nor would I recommend, either
Much simpler would to be to use a precision level, parallel and gage
block(s) to level the lathe ways.
Next I would use a cylinder, turned between centers, that has a near
and far diameter of exactly the same diameter (the middle is not
necessarily important for a machine in good condition). Use this to
set the tailstock position.
It seems the link's attempt is to correct mis-alignment between the
ways and the headstock by stuffing paper under the latter.... a poor
fix, at best. It does not address levelness of the machine nor any
twist in the bed....
If you find vertical misalignment or that the headstock and/or
tailstock axes are no longer parallel with the ways.... rescraping is
Yeah, but that won't do the whole job, will it? Or, let me rephrase:
leveling across the ways won't do the whole job, and I can't level
along the ways because, though I have a very good level, I don't have
anything I can really use as a parallel.
Yes; tailstock's not a problem. I keep just such a bar handy, and
use it to reset the tailstock whenever I've set it over for some
reason. (Note that Rollie's Dad's method doesn't address the
tailstock at all. It's just to get the spindle & ways lined up.)
I grant you, the business about paper is ridiculous. But I have
plenty of decent shim stock around.
Now you've lost me. It doesn't address level, that's true; but it
seems that twist in the bed is precisely what it does address.
BTDT. Fortunately the lathe doesn't need any scraping. The shaper
did, though. It took way too long, but the result was good and, God
help me, I had fun doing it. A lathe bed, OTOH, I'd rather not do.
I'd drink poison long before the job was done.
Thanks for your help. Curious to have your further comments on
Rollie's Dad's method vis a vis twist in the bed.
Well and good, I'm sure, but *start* with a properly leveled machine so it
isn't leaning in any direction. While lathes will run fine out of level,
if you have yours established properly before you make any fine adjustments,
you will be able to rely on the machine being level for certain functions.
Chucking irregular objects in a 4 jaw, using a level for setup, for example.
The minor amount you may be out when you do your final tweaking would be far
better than to have it out a few degrees because you sought a straight cut
without concern for level setup.
The *concept* of shimming the headstock is bizarre, to me! Hell, the
relationship between the two was established at the factory... what
caused it to change since then?
That, I think, is the fallacy of this method. Once you get things bent
around where the indicator is happy with the wobbling rod, how can you
then trust the tailstock... which I'm sure you'll eventually need!
Actually, it seems to approximate some projected spindle axis based on
two points on the rod... as if the headstock was no longer pointing in
the right direction. Most lathe wear is near the headstock... if you
create some axis based on this wear the tailstock is not going to line
up.... especially if you have shimmed something....
Hey there, Harold. The notion of using a level for setup, it's just
foreign to me. Last you knew, I had my machines in the unrenovated
house next door to where I was living: lathe on the sun porch, shaper
in the kitchen, milldrill & bandsaw in the dining room, and all the
floors were made of rubber. If I put a level on my workbench, I
could walk a circle around the bench and watch that bubble go from
one end of the vial to the other. I set each machine up so it was
good if I stood in just the right place, and that was how I worked.
Now that I'm on a decent floor, I still don't have a way to get the
lathe really level. I can get it close, yeah, but to get it right
I'd need a good parallel or at least a longer level than the one I've
got. (I've got a Starrett, a good one, but it's only 8" long.)
No matter: for the time being, I'm still working on a bench that's
not bad, but not great, so perfect levelling is moot. I hope before
long to weld up a good steel cabinet & put the lathe on that. Then,
finally, I'll be able to level the machine for real. Until that
time, it's all a matter of getting things close enough for jazz. It
gripes me, but there it is.
Ah. Confusion. The idea isn't to shim between headstock and ways,
but to shim under the lathe's feet, at the headstock end. If the
method called for shimming between headstock and ways, no, I'd not do
it. But shimming under the feet, well, that's just normal, innit?
Ever read that book Harold? I gave my copy away a few years ago or
I would sent it to you.
1) mount the machine to a solid, unmoving floor.
2) level it with a spirit level.
3) once this is done, then do the final arbiter check for
accuracy: the two collar method.
Interestingly if you read what Hardinge says about setting their
machines up, there is absolutely *no* mention of any kind of
Step one: Plunk the machine down on a solid floor. Step two: drop
down the tab inside the back cabinet so the machine doesn't tip.
Because of the ingenious hardinge kinematic mount for their
beds, a spirit level is not needed at all, nor is any bed
tweaking or leg shimming.
Hold on right there because what you just said makes more
sense that you realize.
"Getting it close enough" actually means something.
It means you've decided on a tolerance for cylindicity of
the parts you make - how much larger diameter can they be on one
side, a certain distance from the other diameter on the other
And it means you have a means to measure that, and to
make corrections in a systematic fashion, to improve the
And it means you are understanding the fundamental limitations
of your equipment (bench stability, floor stability) that
prevents you from achieving an arbitrarily higher level
If you stop and think about it, these are the exact same steps
that any high accuracy endeavor has to deal with. Doesn't
matter if it's +/- 0.005", or +/- 5 microinches. Its the
same plan of action, and there are some folks who *never*
figure this out, and use holy water and magic potions to
line up their machines.
I think you guys are reading it wrong. I took it to mean shimming the
2 corners of the main lathe frame (the ways) to the cabinet to take
out the twist. Now, if your cabinet has 4 adjustable feet, it just
makes the job simpler (and my Myford base does)
Actually, I doubt that it did change from the time it was set up. But if one
expects the tolerance of a $400 machine from China to be as close as those
of a $15,000 machine, you are sadling mistaken.
"Gene Kearns" >
And likely so to others as well, but don't discount if as a viable method of
setting up strange objects. I've done it with success on more than one
occasion. A good example is in setting up a part at an angle. I'm not
suggesting it's something you'd do routinely, but it's yet another of the
tools in the arsenal of skilled craftsmen. Don't close any doors where
machining is concerned. Often the most absurd suggestion is the best
solution to a problem.
I've never invested in a high precision level, either. I use a Starrett
model 98, likely the 8" level of which you spoke. The point is, I know that
my machines are not leaning by a degree or two. To ignore level before
beginning to trim any machine isn't a good idea. Use what you have and hold
your machines as close as possible. That's far better than ignoring the
You might be surprised to find that you can't get your machine properly
leveled, even with a metal bench. All depends on how rigid the bench is, and
how rigid the lathe bed is. My Graziano sits on three points and refuses
to go dead level, with a slight twist at the tailstock end. The only thing
that will correct it is to unbolt the bed from the heavily cast base and
shim, pulling the bed in alignment with the attaching bolts. That's
assuming the base didn't move, and the bed did.
I'm not pleased with it, but the lathe still functions well. And it is,
otherwise, *level*. That means when I lay something on a surface, it isn't
inclined to grow legs and wander off. If for no other reason, machine
tools should be level to avoid that very thing.
Good to see you back.
Compensating for misalignment of headstock to bed by twisting the bed seems
like a recipe for excessive wear to me. I'd recommend buying or borrowing
a precision level, get the bed levelled in both directions with mounts
considerably firmer than paper. Once that is done, then any misalignment
of the headstock can be corrected. Once that's done, things should stay put
and work well long time.
Can't say as though I spent a long interval with it, but a couple years ago
Susan sold one on ebay. It came in a lot of things that was auctioned from
a military installation. Pretty elementary stuff, but all important for
the uninitiated in the way of using a lathe, naturally. Doubtful a
seasoned machinist would learn much. I had a book much like it, sold
originally by Sears (one of which I bought when I purchased my first lathe
in the early '50s). The book went with the lathe when I sold it way back
in the late 50's., a model 109,. 6" machine with the 1/2" -20 spindle that
Exactly my point when I suggested the machine should start out level.
Get it close, fine tune it by turning. Your comments,
" It's all you need to do, and takes > >> nothing besides a micrometer and a
piece of stock in the chuck." conveniently leaves out the leveling process.
I don't recommend it. I get the idea you didn't intend to say it that way,
though, or you wouldn't be quoting from the SouthBend manual.
Chuckle! I'm going to assume you know better than to think you can mount
the typical machine that way. My Graziano, for one, can be placed on the
floor and operated. The heavily cast base is more than rigid enough to
support the bed as it was shipped from the factory----------but they *still*
recommend you level the machine.
It's more involved than their kinematic mount---------mass and rigidity play
a huge role in stability, as you well know. I'd also suggest to you that
modern manufacturing facilities tend towards quite level and flat surfaces.
That's a far cry from some of the older installations, where you likely
couldn't get away with such an installation.
Hardinge machines are solid enough to not demand level for precision. That
doesn't mean you don't benefit (albeit in other ways) by leveling. Many a
machine can be operated successfully at strange angles. It's just not
normally a good idea. Regardless of their ability to run out of level,
leveling their machine, as well as any other, is a good idea, so things stay
where you put them when you let go of them. Have you ever worked on a
surface plate that wasn't level? Need I say more? Also, don't discount
the fact that you may, on strange occasion, wish the machine was level, so
you could use a level for setup. Maybe you haven't done that in the course
of running your machines, but the day will come. It has for me.
As far as I'm concerned, the levelling can be done with a carpenter's
level - it's only done to keep tools from rolling around in the
chip pan. The real accuracy comes from the second step. I've
seen too many folks try to do precision setups with a spirit level,
with the reasoning "well the machine was set up level, so if I
level the workpiece then it will be cut accurate.
In other words, using a level when a good indicator should be
used instead. IMO most folks don't level to make their machine
accurate, they do so to make their setups easier.
Cast iron is not that rigid. The bed will twist - might not be
much, but it will. And that impairs accuracy. But even with a
Graziano, one should still check to see how the machine cuts
once it is levelled.
I would say the hardinge beds are much less rigid than your graziano.
Because the headstock end is supported on two, and only to point contacts,
and the tailstock end is supported by a steel ball in a V-groove, no
gravitational forces can ever impart twist to the bed - and because
the machine was originally set up at the factory with that same mount,
all the accuracy in the initial build is available with no need for an
kind of spirit level.
Because my south bend 10L, which has a bed as sturdy, or even sturdier
than the hardinge machines, has the older leg style bed mount, a twisting
moment is invariably applied between the headstock and tailstock ends.
The key to getting it set up is to get that moment to the correct level.
In a new machine that means 'zero' or, rather, the amount that was there
when it was set up at the factory originally.
Oh, no, not at all! It has always seemed a very sensible (and fast)
way to set up certain kinds of work. Just guessing, I'd think it'd
be more often useful in milling work than on the lathe; but that's
neither here nor there. Reliable people have said that setting up by
level is a tremendous timesaver, and I believe them. But the idea of
doing it on my old shop's trampoline floors? Ha! I remember teenut
once, singing the praises of his level machines and how they made
some setups a breeze; I read his message and laughed, and never
considered it again.
Now, I guess, with decent floors, I can revisit the idea.
Yep, that's the one. Pretty li'l thing and way more precise than the
carpenter's levels I was used to.
True. I really don't know how rigid the lathe is: I don't know what
to compare it to. It's a benchtop unit, a SB 9" long bed. At the
time it was made, it was way more rigid than other lathes in its
class. I don't know how noodly it is next to a new lathe of its
size. I do know it's juuuust a bit more flexy than some two ton
Hardinge. Oh, well. Carefully set up, it's neither too worn nor too
wobbly to cut straight.
As for the bench, we'll see. I'm about one step away from pouring a
couple of concrete pillars and mounting the lathe on them. THAT
would settle a thing or two.
Thanks. It's nice when, for at least a while, life settles down
somewhat. Finally I get to do something about all those castings in
the garage. They've been looknig so forlorn.
I don't get it. Almost any benchtop lathe will twist from its own
weight, right? So what's unusual about shimming to correct it? (As
for paper shims, you'll get no argument from me. I can't think of
anything more Mickey Mouse, except maybe using a sponge.)