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
http://www.john-wasser.com/NEMES/RDMLatheAlignment.html for an
explanation.)

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
bars.

Pete

--
Artful Bodger
http://www.artfulbodger.net

In article , artfulbodger says...

What say you?

Go get a copy of "How to Run a Lathe" from south bend, and perform
their two collar test. It's all you need to do, and takes
nothing besides a micrometer and a piece of stock in the chuck.

Jim


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jim rozen wrote:

Go get a copy of "How to Run a Lathe" from south bend

Got it, but it's been a long time since I've read it. Thanks, Jim,
I'll have a look.

Pete

--
Artful Bodger
http://www.artfulbodger.net

"jim rozen" wrote in message
...
In article , artfulbodger says...

What say you?

Go get a copy of "How to Run a Lathe" from south bend, and perform
their two collar test. It's all you need to do, and takes
nothing besides a micrometer and a piece of stock in the chuck.

Jim


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.

Harold

Harold and Susan Vordos wrote:

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.

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.

Pete

--
Artful Bodger
http://www.artfulbodger.net

In article , artfulbodger says...

...Until that
time, it's all a matter of getting things close enough for jazz. It
gripes me, but there it is.

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
side.

And it means you have a means to measure that, and to
make corrections in a systematic fashion, to improve the
tolerance level.

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
of accuracy.

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.

Jim


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On 10 May 2005 19:45:55 -0700, jim rozen
wrote:

In article , artfulbodger says...

...Until that
time, it's all a matter of getting things close enough for jazz. It
gripes me, but there it is.

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
side.

And it means you have a means to measure that, and to
make corrections in a systematic fashion, to improve the
tolerance level.

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
of accuracy.

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.

Jim
Jim,
I tried that holy water business and the machine just rusted. Magic
potions are out too. Ever seen a witch? No, what works best is Maiden
Juice and epithets. I learned this from the first machine shop I
worked in. Almost all the work we did was close tolerance. The boss
always said to put Maiden Juice on it. And then he'd cuss until things
worked out. Unless his wife was around.
ERS

jim rozen wrote:

...Until that
time, it's all a matter of getting things close enough for jazz. It
gripes me, but there it is.

"Getting it close enough" actually means something.

Yessir, it sure does. There's a lot of talk about dead level, dead
true, dead flat, dead straight, and plain ol' dead nuts. It's a
convenient way to talk, and fine as long as nobody forgets that it
means "the best I can measure with my tools." But slang has a way of
taking over, so that people think it actually means what it seems to
mean.

It means you've decided on a tolerance.... And it means
you have a means to measure that, and to make corrections....
And it means you are understanding the fundamental limitations
of your equipment....

Yepyepyep. It was a bit of a stunt to get things "close enough" for
the last few projects I completed. Some of them needed careful work,
and I was bumping up against the limitations of my shop (and my
skill). But close enough was just close enough, and the results made
me proud.

Upcoming tasks are more demanding: before I'm done, I'll have had to
buy a much more serious mill and probably a bigger lathe, too.
$$$$$$$$ sigh. But for now, I can at least get a start on the
smaller parts. Looks like I'll be able to make my "close enough" a
lot closer than it was in the old shop.

there are some folks who *never* figure this out, and use
holy water and magic potions to line up their machines.

Oh, hey, I'm all for it. Sacrificing a chicken couldn't hurt,
either.

Pete

--
Artful Bodger
http://www.artfulbodger.net

"artfulbodger" wrote in message
...
Harold and Susan Vordos wrote:

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.

Hey there, Harold. The notion of using a level for setup, it's just
foreign to me.

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.

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.)

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
issue.


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.

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.

Harold

Harold and Susan Vordos wrote:

The notion of using a level for setup, it's just foreign to me.

And likely so to others as well, but don't discount if as a viable method of
setting up strange objects.

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.

I've never invested in a high precision level, either. I use a Starrett
model 98, likely the 8" level of which you spoke.

Yep, that's the one. Pretty li'l thing and way more precise than the
carpenter's levels I was used to.

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.

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.

Good to see you back.

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.

Pete

--
Artful Bodger
http://www.artfulbodger.net

In article , Harold and Susan Vordos says...

Go get a copy of "How to Run a Lathe" from south bend, and perform
their two collar test. It's all you need to do, and takes
nothing besides a micrometer and a piece of stock in the chuck.

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.

Ever read that book Harold? I gave my copy away a few years ago or
I would sent it to you.

They say:

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
spirit level.

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.

Done.

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.

Jim


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==================================================
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==================================================

The Colchester Chipmaster has the base mounted on 3 points onto the
floor so it is automatically free of twist
Geoff

"jim rozen" wrote in message
...
In article , Harold and Susan Vordos says...

Go get a copy of "How to Run a Lathe" from south bend, and perform
their two collar test. It's all you need to do, and takes
nothing besides a micrometer and a piece of stock in the chuck.

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.

Ever read that book Harold? I gave my copy away a few years ago or
I would sent it to you.

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
bent easily.

They say:

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.

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.


Interestingly if you read what Hardinge says about setting their
machines up, there is absolutely *no* mention of any kind of
spirit level.

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.

Done.

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.

Jim

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.

Harold

In article , Harold and Susan Vordos says...

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.

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.

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.

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.

It's more involved than their kinematic mount---------mass and rigidity play
a huge role in stability, as you well know.

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.

Jim


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Harold and Susan Vordos wrote:

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.

It's more involved than their kinematic mount....

Could someone describe the kinematic mount? I'm a curious guy.

Pete

--
Artful Bodger
http://www.artfulbodger.net

"artfulbodger" wrote in message
...


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
bars.

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.

Don Foreman wrote:

Compensating for misalignment of headstock to bed by twisting the bed seems
like a recipe for excessive wear to me.

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.)

Pete

--
Artful Bodger
http://www.artfulbodger.net

On Wed, 11 May 2005 14:31:11 GMT, artfulbodger
wrote:

Don Foreman wrote:

Compensating for misalignment of headstock to bed by twisting the bed seems
like a recipe for excessive wear to me.

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.)

That's the point: shim it so it's level and not twisted, rather than
shimming it to deliberately twist it to correct another
misalignment.

In article , Don Foreman says...

That's the point: shim it so it's level and not twisted, rather than
shimming it to deliberately twist it to correct another
misalignment.

In this case often the shimming is done to counteract the
effects of wear, so the machine turns and bores straight.

To put this in perspective, the shims involved in getting
a small floor mounted lathe dialed in for the last thou
of accuracy over, say, a six inch long part, might be
0.015 inch at the legs. So the shift in the bed is going
to be a couple of thousanths or so. Not much.

Jim


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Stress is force and strain is displacement, right?

If there were no gravity, one would merely puddle mortar or expoxy at
each foot, allow to cure, turn gravity back on, then begin operations.
This would assure the lowest stress mounting, and you'd figure that
would produce the lowest strain mounting.

Without a gravity switch, would it be right to have adjusters or shims
at each foot such that a separate piece of shim stock, the same size at
each foot, could be pulled with a tension meter, assuming friction
conditions were the same at each foot, to even the load on each foot,
or conform these loads to a chart of the way they should be, as a first
step?

I get this idea from taking off the front of our dryer. It's a big
floppy assembly with the panel off, but when in place, it's 250 pounds
and more, solid. So I was thinking that when I was replacing the
rollers for the dryer, the thing to do would be to adjust the feet so
the rollers contacted the drum evenly. The dryer's four feet, two fixed
rear and two adjustable front, are redundant.

It's a question of kinematic redundancy. A lathe with two headstock
feet and a single tailstock foot would be ideal. It seems you could
plunk such on a level floot and go right to work because three point
contact defines the position.

--Doug

wrote:

A lathe with two headstock
feet and a single tailstock foot would be ideal. It seems you could
plunk such on a level floot and go right to work because three point
contact defines the position.

I don't know why all lathes, or at least all benchtop lathes, aren't
made with three feet. There's no such thing as a wobbly three-legged
stool.

I've thought of putting an iron block under the tail-end feet of my
lathe: both feet would bolt to it, and its bottom would be a shallow
vee. There would be a narrow land in the center, with a single bolt
hole for mounting to the bench. Of course I'd put the head end on a
similar, but flat bottomed, block.

The only problem I can think of is that everything could end up too
flexible. I don't know. Would my nice, fairly stiff lathe get all
vibratey if I did this? Anyone got any thoughts about it?

--
Artful Bodger
http://www.artfulbodger.net

In article ,
artfulbodger wrote:
wrote:

A lathe with two headstock
feet and a single tailstock foot would be ideal. It seems you could
plunk such on a level floot and go right to work because three point
contact defines the position.

I don't know why all lathes, or at least all benchtop lathes, aren't
made with three feet. There's no such thing as a wobbly three-legged
stool.

Consider the possibility of the bed having machined without
sufficient time for it to stress relieve. (They used to allow them to
season for some time after roughing before final machining.)

Now, the bed will warp *after* final machining. With a
three-point suspension, you have no way to apply stress to cancel that
warp. With four-point, you are fine.

Of course, jeweler's lathes are single-point support -- a column
under the headstock end. But the overall design suggest to me that
there is very little need to make provisions for corrective stress on
those -- there is a *lot* of meat in the beds for their size.

Now -- also think of a long bed lathe, with a fairly heavy cut.
This could introduce twist to the bed under load -- either a cut from
the carriage, or twist applied by driving a big drill bit into the
workpiece. For something like this, the four-foot design gives it extra
anti-twist support.

But -- FWIW -- the Atlas/Clausing 6x18 lathe has a three-point
mounting -- at least my old one with sleeve bearings and a blue paintjob
does. I believe that the later ones with the ball or tapered roler
bearings in the headstock have the four-point mounting.

I've thought of putting an iron block under the tail-end feet of my
lathe: both feet would bolt to it, and its bottom would be a shallow
vee. There would be a narrow land in the center, with a single bolt
hole for mounting to the bench. Of course I'd put the head end on a
similar, but flat bottomed, block.

The only problem I can think of is that everything could end up too
flexible. I don't know. Would my nice, fairly stiff lathe get all
vibratey if I did this? Anyone got any thoughts about it?

Try it and find out. Try heavy drilling with a Morse taper
twist drill in the tailstock taper. Try heavy cuts near the end of the
bed. See what happens.

Be prepared to make a second tailstock end block with all four
feet if it introduces problems.

And report back on your results.

Right now, I like the four-foot mount for my Clausing, with
factory supplied hollow bolts threaded through the feet, and smaller
bolts through it all to clamp it down to the factory pedestal. I did
have to do a bit of tuning to get everything level. And that was not
that long a bed (24" between centers) for the size of the swing (12")
and the bed width.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
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--- Black Holes are where God is dividing by zero ---

On Tue, 10 May 2005 17:33:20 GMT, artfulbodger
wrote:

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
http://www.john-wasser.com/NEMES/RDMLatheAlignment.html for an
explanation.)

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
bars.

Pete

Pete, I've had to rely upon Rollie's Dad's method and it has worked
very well for me.

Like others have said, level the lathe using a precision level. Then,
if you feel a need to check headstock alignment, use R-D-M.

In my case, I bought a used lathe that was in good shape, but I knew
something was amiss when I spotted a crude shim between the headstock
and the bed. Many days of bluing and scraping along with R-D-M to
check my work eventually paid off. I really enjoy using that lathe,
now.

Regards,

Orrin

Orrin Iseminger wrote:

... I bought a used lathe that was in good shape, but I knew
something was amiss when I spotted a crude shim between the headstock
and the bed. Many days of bluing and scraping along with R-D-M to
check my work eventually paid off.

I guess a lotta work can be involved in that, but it doesn't scare me
like the thought of scraping down the bed. Mine is only a 9" lathe,
but the bed is five feet long, and that's a great big arena for
making mistakes. I don't know what Joe HSM would use for a
straightedge; but even with the proper tools, it would be hard to
scrape the whole bed straight.

God help me, I kind of enjoy scraping. I don't know why. I think it
has to do with making a reeeeeally true surface out of thin air. But
I'm still glad that my lathe only needed scraping on the tailstock.
It was a nice, bite sized job.

Pete

--
Artful Bodger
http://www.artfulbodger.net

I think Rollie's Dad's method is rather ingenious. The primary purpose
is to remove the twist from the bed. It won't ensure the lathe is level
from end-to-end or side-to-side. The purpose of leveling the lathe
isn't to have it level, it's to remove the twist in the bed so that the
the orientation of the headstock/tailstock/carriage are the same as the
tailstock/carriage travel up and down the ways. The machining operation
could care less if one side/end of the lathe is higher than the other.

I've done it both ways and Rollie's Dad's method produces perfectly
adequate results. It will also detect whether the headstock is
pointing up/down relative to the bed. Much more difficult to fix,
though. And not guaranteed from the factory. Best of luck.

John wrote:

I think Rollie's Dad's method is rather ingenious. The primary purpose
is to remove the twist from the bed. It won't ensure the lathe is level
from end-to-end or side-to-side.

Yeah, that's the impression I had. I used the method to straighten
out the lathe and it worked well; but now I've gone and leveled
everything anyway. Or, as close as I can get to level, with my
(inadequate, temporary) bench. I wasn't going to bother, but then
decided to scrape in the new cross slide. This of course leads to
scraping in the compound rest and the saddle, and oh boy, I'm off and
running. Fortunately, I can't scrape the bed, can't even really
check if it needs it, until the lathe is on a better mounting. But
it's level enough to scrape and fit the other parts well, so here I
go.

Blue hands, sore shoulders, God help me.

--
Artful Bodger
http://www.artfulbodger.net