# New Lathe Twisted bed



## Versacon7 (May 17, 2017)

Hi Guys-
I'm a newbie to this forum and have been hobby machining for 50 years (since junior high). I just bought a new 14x40 gunsmith lathe and am setting it up. I leveled (10" Mitutoyo) the bed as follows: I first leveled the closest way from side to side. I then leveled the tail stock end from front to back. Lastly I tried leveling the spindle end front to back. It is down on the far way by .007. I think the bed is twisted. I have yet to cut a blank to see what happens but I don't think I want to go that far until I get the bed straight. I went ahead and bolted the base to the concrete slab in my shop as I leveled the machine. When I found the outside spindle end down, I tried shimming up the cast bed frame up .007 to see if I could get it to move. Nothing moved. I actually didn't think I could get it to move but I thought I would give it a try. By the way, When I measure the ways at the mid point, it is also down .003. So It seems to be twisted progressively. I'm thinking I could probably correct for this by adjusting the headstock case by re-aiming it. I prefer to have everything level instead. 
Any ideas how to remedy this?


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## Bill Gruby (May 17, 2017)

Call the manufacturer or people you bought it from. This should not happen with a new lathe.

 "Billy G"


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## Versacon7 (May 17, 2017)

I agree and did. They told me to unbolt the bed from the stand and see if it relaxes over a month or so...
I'll give it a month and probably send it back. I cringe at re-crating it and sending it 1,000 miles.
If I could fix the twist, it might be easier than sending it back. 
Versacon


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## Uglydog (May 17, 2017)

You paid for a good lathe bed.
You shouldn't have to wait a month to identify if there is a problem.
If you need to send it back will they pay for your re-crating/palatalizing?
How does the warranty read?

Daryl
MN


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## fradish (May 17, 2017)

When you said you shimmed the bed up 0.007, did you try any more than that?

I just setup my lathe recently and I didn't bother that much with leveling.  I used a carpenters
level to get it as close as I could, made a 1" test bar with two 2" aluminum collars about 10"
apart and took a test cut.  If the tailstock collar was bigger than the headstock collar I raised
the front foot of my lathe bench (on the tailstock end) and took another cut.  If the headstock collar
was bigger I lowered the front tailstock foot.

I don't have my bench anchored to the floor, so at a certain point raising the front corner caused the
back corner to raise up a bit.  I then had to shim the foot of the lathe on the tailstock end, over correcting
this time and then at that point I could just mess with the bench foot levelers until I got the 2 collars
within 0.001" of each other.

I don't want my lathe so far out of level that things roll around in the chip pan, but I don't think
it is that important.  I think getting the twist out is more important and (for me at least) the
simplest way was with the test bar.

I'm really not that experienced, so please take my comments with a grain of salt.  My lathe is a small
12" lathe, but when I started, I had over 0.020" difference between the 2 collars with the lathe sort-of
leveled with a carpenters level.  But with the test bar I was able to get that down to 0.001".  I haven't
re-checked to see how level the lathe is since then.


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## Versacon7 (May 17, 2017)

Uglydog said:


> You paid for a good lathe bed.
> You shouldn't have to wait a month to identify if there is a problem.
> If you need to send it back will they pay for your re-crating/palatalizing?
> How does the warranty read?
> ...



I’m sure they will take it back. I was assuming they won’t send someone here to crate it…

I was trying my best to work with them…

Grizzly is the seller. My past experience with them on other machinery has been outstanding…
Versacon


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## Mister Ed (May 17, 2017)

To me, it does not surprise me that the lathe won't level on the first shot ... new or not. You have to figure it has been in a crate, bolted to a wooden base for who knows how long. I suspect the twist will work itself out given a little time to relax and attention in the right place.

Case in point, when I moved in my "new" (54 year old) 12" Logan and then went to level it 2 weeks later ... I had a heck of a time and thought after session #1 ... WTH did I just buy. I had 10-15 thou/ft difference between ends. Trying to adjust more, left an opposite leveler hanging in the air. A day or two later the lathe had relaxed and that hanging leveler was sitting on the floor. Went back at it and was able to level it in to 2 thou per foot (or less). In a week or two I will go back at it again.


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## Versacon7 (May 17, 2017)

fradish said:


> When you said you shimmed the bed up 0.007, did you try any more than that?
> 
> I just setup my lathe recently and I didn't bother that much with leveling.  I used a carpenters
> level to get it as close as I could, made a 1" test bar with two 2" aluminum collars about 10"
> ...



It didn't budge after .007 shim. I really don't think it will and I don't want to break the cast iron anywhere.
I think I'm going to be patient. Ultimately, I think it will be going back to the manufacturer...
Versacon


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## Versacon7 (May 17, 2017)

Mister Ed said:


> To me, it does not surprise me that the lathe won't level on the first shot ... new or not. You have to figure it has been in a crate, bolted to a wooden base for who knows how long. I suspect the twist will work itself out given a little time to relax and attention in the right place.
> 
> Case in point, when I moved in my "new" (54 year old) Logan and then went to level it 2 weeks later ... I had a heck of a time and thought after session #1 ... WTH did I just buy. I had 10-15 thou/ft difference between ends. Trying to adjust more, left an opposite leveler hanging in the air. A day or two later the lathe had relaxed and that hanging leveler was sitting on the floor. Went back at it and was able to level it in to 2 thou per foot (or less). In a week or two I will go back at it again.




This is why I'm willing to wait and see. 
Versacon


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## chips&more (May 17, 2017)

Some lathes are so rigid, you can set them on a river bed of rocks and you cannot twist the bed. Other lathes will follow the floor irregularities and telegraph that problem into the lathe bed. So…are you twisting the bed? Or did you get the bed already twisted?


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## Versacon7 (May 17, 2017)

chips&more said:


> Some lathes are so rigid, you can set them on a river bed of rocks and you cannot twist the bed. Other lathes will follow the floor irregularities and telegraph that problem into the lathe bed. So…are you twisting the bed? Or did you get the bed already twisted?



I got the bed twisted. When I contacted their support, they said loosen everything up wait a month and see if it relaxes.
I'm crossing my fingers... But I can't believe it will relax that much. Just going to wait and see I guess.


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## wrmiller (May 17, 2017)

I've been told that the 12-14" lathes are very sensitive in this regard. Anytime I buy a new lathe or even just move one like I just did, I get it up on the stand and let it set for several days to a week or more to allow the cast iron to relax prior to leveling. Mine just sat on wood pallets for almost 9 months until I got it set up on it's stand last week. Did the final leveling and test cuts yesterday and everything worked out fine.

My suggestion would be to follow Grizz's suggestions and see what happens. Not sure I'd wait a month though unless the lathe went through some severe temperature/humidity changes in getting to you.


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## epanzella (May 17, 2017)

I had the same situation with my G4003G. The bed is so stiff that after making an adjustment I had to wait a day or two for it to bend. After a few rounds of adjustments it's within .001 on 10 inches now.


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## Bob Korves (May 17, 2017)

You said you leveled the tailstock end first.  I would do the headstock end first, and then let the tailstock end settle a bit and then see what you have.  Leave any bolts holding it to the floor loose until you get things sorted out.  I also suppose that floor anchors that cause a solid connection to the lathe could cause twist in the bed if they do not have side to side and front to back clearance in all the lathe foot holes.


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## coolidge (May 17, 2017)

> I went ahead and bolted the base to the concrete slab in my shop as I leveled the machine.



Unbolt it, a Grizzly welded steel stand bolted down not a good idea. Unbolt it and level the lathe front to back head stock/tale stock.


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## scwhite (May 17, 2017)

Versacon7 said:


> I agree and did. They told me to unbolt the bed from the stand and see if it relaxes over a month or so...
> I'll give it a month and probably send it back. I cringe at re-crating it and sending it 1,000 miles.
> If I could fix the twist, it might be easier than sending it back.
> Versacon


Sometimes it will take a year or more of levelling 
The lathe every three months for the bed to go back 
To where it should be


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## wrmiller (May 17, 2017)

coolidge said:


> Unbolt it, a Grizzly welded steel stand bolted down not a good idea. Unbolt it and level the lathe front to back head stock/tale stock.



Oh yea, good point. Didn't realize he was bolting a steel stand to the floor.


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## scwhite (May 17, 2017)

Mister Ed said:


> To me, it does not surprise me that the lathe won't level on the first shot ... new or not. You have to figure it has been in a crate, bolted to a wooden base for who knows how long. I suspect the twist will work itself out given a little time to relax and attention in the right place.
> 
> Case in point, when I moved in my "new" (54 year old) 12" Logan and then went to level it 2 weeks later ... I had a heck of a time and thought after session #1 ... WTH did I just buy. I had 10-15 thou/ft difference between ends. Trying to adjust more, left an opposite leveler hanging in the air. A day or two later the lathe had relaxed and that hanging leveler was sitting on the floor. Went back at it and was able to level it in to 2 thou per foot (or less). In a week or two I will go back at it again.


This is what I am going through now on my 
10" Clausing . It has been a full year and five months 
And I am getting ready to do the bolt down 
Now and level it agin. Keeping a lathe level 
Is critical to it opartion . The last time I levelled it was about four months ago . It was about .003 out 
Total


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## Bob Korves (May 17, 2017)

I see no need to bolt down hobby lathes to the floor, and multiple reasons why not.


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## 4GSR (May 17, 2017)

My 13' and 15" Sheldon's will level up, but every time you look at it, it would move literally.  My 20" L & S lathe, you couldn't get the bed to twist on it.  I'd get it level at the headstock and go to the far end, it would be level, but the leveling screws on one side of the bed would not be touching and it had a center leg too.
As for the bed being level from left to right, let the tailstock end of the bed be lower than the headstock end.  It does not need to be level.   Ad I agree with everyone else's comments on level the headstock end first and let the tailstock end float for a month or so, then start jacking the leveling screws a little at a time and give it a month between adjustments until you get it level.  After that, check it about every six months or more.


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## wrmiller (May 17, 2017)

Bob Korves said:


> I see no need to bolt down hobby lathes to the floor, and multiple reasons why not.



True that! (I used to live in earthquake country...err...CA)


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## Versacon7 (May 17, 2017)

wrmiller said:


> I've been told that the 12-14" lathes are very sensitive in this regard. Anytime I buy a new lathe or even just move one like I just did, I get it up on the stand and let it set for several days to a week or more to allow the cast iron to relax prior to leveling. Mine just sat on wood pallets for almost 9 months until I got it set up on it's stand last week. Did the final leveling and test cuts yesterday and everything worked out fine.
> 
> My suggestion would be to follow Grizz's suggestions and see what happens. Not sure I'd wait a month though unless the lathe went through some severe temperature/humidity changes in getting to you.



Thanks for all the suggestions guys!
I think I'm going to follow Grizzly suggestions. I'll keep monitoring it in the next couple of weeks to see if anything changes. If not I'll discuss with Gizzly as I had originally intended. It sounds like it's not an uncommon condition though and that's a little more comforting.
Time will tell.
Thanks again.
Versacon


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## tq60 (May 17, 2017)

Cabinet mounted lathes usually do not need bolting to floor.

So first action is remove all floor bolts then place washers under or adjust feet just to have cabinet not rock.

Now level front to back at headstock then same at tail stock.

Length wise does not matter yet.

It will not Un - twist yet but add height to low side until high side is not touching the floor and leave it alone.

It will settle down so place a sheet of paper under it and make sure it can move.

Use your foot to slide it and when it stops the lathe has touched down.

Re level and repeat.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk


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## Versacon7 (May 17, 2017)

tq60 said:


> Cabinet mounted lathes usually do not need bolting to floor.
> 
> So first action is remove all floor bolts then place washers under or adjust feet just to have cabinet not rock.
> 
> ...




That makes sense-
I'll give it a try-

Versacon


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## scwhite (May 18, 2017)

Bob Korves said:


> I see no need to bolt down hobby lathes to the floor, and multiple reasons why not.


My lathe sets on  sheet metal cabinets . All the weight is up high . It is very top heavy .
    It moves sometime just taking the 8" four jaw chuck off the spindle it will rock side to side a little .
    I will set the  anchor bolts till they just kiss off on top of the four legs . I hope this will help stop
The side to side movement .
     This is a very light weight lathe 800 or 900
Lbs at the most . I am looking for something
Bigger in the 3000 lb range .


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## Bob Korves (May 18, 2017)

scwhite said:


> My lathe sets on  sheet metal cabinets . All the weight is up high . It is very top heavy .
> It moves sometime just taking the 8" four jaw chuck off the spindle it will rock side to side a little .
> I will set the  anchor bolts till they just kiss off on top of the four legs . I hope this will help stop
> The side to side movement .
> ...


Your Clausing is in no risk of falling over unless you run into it with a car or fork lift or similar.


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## mcostello (May 18, 2017)

I have a 15" X 50" Clausing Colchester and have the same problems, it's just not small lathes.


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## Bob Korves (May 18, 2017)

Lathes do not need to be level, or straight.   They need to produce accurately cylindrical work as well as possible with the carriage along the entire bed of the lathe.  Depending on wear, accuracy of manufacture, and other issues, level and without twist may not be what works best to achieve overall accuracy for the work you do the most.  Level is not really a factor anyway (other than for where the oil runs to in the chip pan) it is just an often used starting point, hoping for something perfect from the factory or from the previous users.  We do what we need to, whatever makes it best produce cylindrical work.  Resetting the headstock, offsetting the tailstock, twisting the bed, and ultimately reconditioning the ways are just some of the ways to do that.  Whatever makes good parts.  Each lathe is a separate case.


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## 4ssss (May 18, 2017)

Your new lathe is off .003, the thickness of an average hair over a 40 INCH span.  You do know that the floor in your shop is going to move at some rate over time, it wouldn't surprise me to see it move in the time it takes you to read this.  Even the OD grinders in the shop I worked for were leveled without the help of a $1000 Starett level, and I doubt that shops that work on space shuttle parts are that precise. Don't take this the wrong way, but personally I think you're being way too picky


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## 4GSR (May 18, 2017)

Bob Korves said:


> ..............................  Each lathe is a separate case.



Bob,

You are  absolutely correct!!!!  

Each one has to be treated a different way.  

Ken


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## Silverbullet (May 18, 2017)

Out of a China lathe , what do you really expect , we all want a top notch part when we make them . But a lot of it is the machinist , not the machine.
If you get it level then what? If your tailstock or head stock is not aligned. Do you reset everything . I agree the lathe should be level but to what extent .007 in 40" . Should not  stop the lathe from turning out good parts accurately. I'd Ck the alignment over the bit of level it's off. But I'm a hobbiest now not working for NASA so my tolerances aren't that critical. The others have also stated the weather , the earth are always moving . Good one day may not be better then yesterday. It will change not  many places bolt them down , most concrete pads are tapered for water run off , my garage is sloped 2" in 20' , yet the apron is 2" in 10' . When my compressor wasn't piped outside it would run all the way to the street. How to help change just try totally loose the anchors  and let the lathe regain its shape. It will move on its own , if you try forcing it I'd bet money it will crack or bust.


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## benmychree (May 18, 2017)

Straining a lathe bed to straighten it out to level is not going to break it; we think of cast iron as being brittle and inflexible; brittle, it can be, but inflexible it is not; I had a lathe, a 14" Lodge & Shipley toolroom model that would not cut straight, and the bed proved to be twisted, likely from not being leveled for a long period of time; you could level the head end, then attempt to level the tail end and the rear leg would be off the ground and still not level; a heavy weight was placed in the pan behind the lathe to bring it down to level, then it would cut straight.  The same effect can be had by bolting all four legs to the floor and shimming or adjusting leveling bolts until true level is had.  A carpenter's level or even a .005" per foot millwright's level is not good enough for precision leveling, the normal precision level is .0005 per foot.
That said, one does not really need a precision level to get a lathe to cut straight; level the head end with an ordinary level and level the length of the bed to approximate level, then adjust the leveling of the tail end until the lathe cuts straight, using a test bar with 2 narrow bands at either end and chucked in the spindle; cut a fine cleanup cut on each and note the difference in diameter; if small on the tail end, shim up or adjust the rear leg until it cuts the same diameter at both ends; if anything leave it alone if the cuts are SLIGHTLY larger at the head end.
A good example of flexibility was a horizontal boring mill I bought about 30 years ago; when I first set it up, it cut out of square vertically with the head leaning inwards towards the table; I leveled the bed, but left the leveling screws of the column a little loose at the far end; over the years it sagged back to its level position and will now cut square with the table.  I could have hastened the process by bolting it to the floor, but in the building I was in at the time the floor was thin and poor and I did not want to drill holes in the floor either; in its new home it just sits on leveling pads and is so heavy that movement is not a problem; I think I remember it being about 17,000 lbs.
If a lathe bed is leveled accurately and still cuts taper, my fix is to shim the headstock until the taper is removed; on a lathe with one prismatic way and one flat way, I insert a shim on the opposite sides at each end of the prismatic way until taper is removed; the proper way would be to re scrape the surfaces under the headstock, but for most purposes, the shimming is effective.
If one makes a test bar and finishes both bands to the same diameter, and dial indicator can be used to show inaccuracies in alignment, both laterally and vertically; if there is a difference in readings on top of the test bar, this can also effect cutting tapered, although not as much as the lateral difference.   I have done this on several lathes that I have owned over the years and it makes it very much easier to do precision work without resort to (all to) much filing and polishing.


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## fradish (May 18, 2017)

To further what benmychree said, even something as brittle as glass can flex quite a bit before breaking.
You can see this in large panes of glass when the pressure in a building changes, like when a door to the
outside is opened or closed.

I think the thing you have to worry about is the distance over which you are flexing the material.  If you have
a piece of cast iron and attempt to flex it 1/8" over a distance of 1", you probably will crack it.  But 1/8" over
a foot probably would not (just a guess.)   I think if you shim up one part of your lathe, if you have your shim
stock around the bolt hole so that it is supported from the stress of tightening the bolt you'll probably be ok. 
Now I'm not saying shim it 1/8", but .010" or 0.020" probably wouldn't be a problem.


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## benmychree (May 18, 2017)

fradish said:


> To further what benmychree said, even something as brittle as glass can flex quite a bit before breaking.
> You can see this in large panes of glass when the pressure in a building changes, like when a door to the
> outside is opened or closed.
> 
> ...


And I would add that the likely shimming to achieve straightness in any case would be just several thousandths, that has been my experience.


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## 4GSR (May 18, 2017)

Don't get too carried away bending/twisting a bed.  I've seen broken lathe beds in past lives. 

Edit: I've also seen big lathe beds with unbalanced loads twist, rock and roll to the point of breaking.  Yeah, cast iron does have a little elasticity to it's iron make up.  Just depends on how much "alloying" is done the the iron in the melting stage.  And when it hits that point of breaking, it will snap off with a bang!


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## scwhite (May 19, 2017)

Bob Korves said:


> Your Clausing is in no risk of falling over unless you run into it with a car or fork lift or similar.


I didn't say it was going fall over
Or even thought it would turn over .
     It is just tipsy and needs to be stable


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## Mister Ed (May 19, 2017)

4gsr said:


> And when it hits that point of breaking, it will snap off with a bang!


That would actually be interesting to see in a video.
Anyone want to volunteer??


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## 4GSR (May 19, 2017)

Mister Ed said:


> That would actually be interesting to see in a video.
> Anyone want to volunteer??


I have broken off cast iron components in testing under controlled conditions over the years, trying to get a good sound product.  The industry I work in, we take cast iron, which is not allowed as pressure containing materials per ASME rules, and make it hold pressure.  Of course in actual applications, it is planted down hole in the oilfield, where it is of no harm to anything living.  Tensile testing of cast iron is interested, you don't get that sudden .2% drop in tension and go up the scale before its breaks.  It go up the scale and boom, its over with.

EDIT: I correct myself, when cast iron breaks, it don't go boom, just goes "crunch"  It's steel that goes "boom" when it breaks in tension. Sorry.


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## Splat (May 19, 2017)

You did right by anchoring the stands to the floor. Hopefully you leveled them while anchoring to get them as level as you could. A lathe should be rigid. Anchoring it helps with that. I remember after securing my lathes to the floor what a difference it made. Also it prevents movement across the floor. After taking your precious time to carefully level your lathe that all disappears if the lathe moves across your floor and throws your level off.

So after anchoring and leveling the plinths it's time to sit the lathe on them, but don't bolt it down. Wait a few days to let the cast iron relax. I gave mine a week and then bolted it down to the stands. Put your machinist's level on the cross slide perpendicular to the ways and run the carriage to the headstock and note your level's bubble position. Now run the carriage down to the tailstock end and again note the bubble. Shim between lathe and plinth as needed to get the bubble in the same spot at both ends of the ways. How level the lathe is parallel to the ways doesn't mean much. I have my lathes sitting higher at the tailstock end for coolant purposes. Get your lathe ways level and then do the 2-collars test. Shim again as needed to get the 2 collars as close in diameter as possible.  After a week check level again. I check mine once a month.


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## MattM (May 21, 2017)

Last I heard ships at sea have machine shops and those machine shops have lathes and those ships are seldom if ever level.

Tell me why I should be concerned about my lathes being "level".

That being said my lathes and mill are level to the best  that I and Starret can make them.


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## benmychree (May 21, 2017)

Machinery at sea need not be "level", but do need to be in alignment, that is, not twisted or otherwise distorted.


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## kvt (May 21, 2017)

There are different types of level.  Level relative to level is one and then  Level to the floor,  is another one.   as I think I have seen on here somewhere before,   It does not have to be level in the traditional sense,   But has to be level in a relative since,     Think of it this way,   If the floor slopes at a 2 degree angle,   front to back and a 3 degree angle left to right,   Then if you wanted it flat on the floor,   your ways would actually be on a 2 degree from headstock to tail stock.   and 3 degrees front to back.    you would adjust your level to show level when set on this,  then verify your head stock is level to that,   then move down toward the tail stock and verify it is the same.   It can be a pain to level this way on a sloped pad/floor, but some people do that rather than having to build up or jack up one end that much.  or at least that is what I see and have seen.  No formal training on any of this.  just reading such.   this site has helped a lot.


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## benmychree (May 21, 2017)

Yes, true; in fact, Warner & Swasey, manufacturer of turret lathes made just such an adjustable level with the vial fastened at one end and adjustable by knurled screw at the other end.


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## wrmiller (May 21, 2017)

Folks have been mangling the English language (or any language for that matter) since language was invented. 

It might be more accurate to use the word 'truing' when describing lathe adjustments. The bed doesn't have to be level per se, but the headstock end of the bed needs to be on the same plane as the tailstock, front to back, to remove twist. Left to right is a don't care.

You could mount your lathe to the side of your house if you wanted to, as long as the bed is twist free. But if you do, I want pics!


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## benmychree (May 21, 2017)

wrmiller said:


> Folks have been mangling the English language (or any language for that matter) since language was invented.
> 
> It might be more accurate to use the word 'truing' when describing lathe adjustments. The bed doesn't have to be level per se, but the headstock end of the bed needs to be on the same plane as the tailstock, front to back, to remove twist. Left to right is a don't care.
> 
> You could mount your lathe to the side of your house if you wanted to, as long as the bed is twist free. But if you do, I want pics!


The exception to the statement that level does not matter so long as both ends of the lathe are in the same plane is with lathes that have three or more sets of legs, common on longer machines; in order to "level" them as a practical matter one must have them level in both directions to ensure that the ways are not high or low in their length, in the case of a very long machine, like an ocean wave, although, machines in this class can be "leveled" by a laser,  I saw a large lathe, 16 ft. swing and over 100 ft. between centers that was leveled by conventional means and failed to deliver work of sufficient precision; after laser leveling it preformed satisfactorily.


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## wrmiller (May 21, 2017)

As a simple hobby machinist, I have no experience with lathes that large. Exception duly noted.


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## 4GSR (May 21, 2017)

benmychree said:


> The exception to the statement that level does not matter so long as both ends of the lathe are in the same plane is with lathes that have three or more sets of legs, common on longer machines; in order to "level" them as a practical matter one must have them level in both directions to ensure that the ways are not high or low in their length, in the case of a very long machine, like an ocean wave, although, machines in this class can be "leveled" by a laser,  I saw a large lathe, 16 ft. swing and over 100 ft. between centers that was leveled by conventional means and failed to deliver work of sufficient precision; after laser leveling it preformed satisfactorily.


I have a transit my dad used to use for leveling long lathe beds.  He used to level deep hole trepanning machines, which some of them had bed lengths of over 120 foot in length.  Most were in the 40 to 60 feet in length.  A transit can get a bed level level within a couple of thousandths in ten feet under the right conditions.  As mentioned, lasers are more common to use.  You still have a margin of error with either method used as well as how stable of an foundation you have for the machine.


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## benmychree (May 21, 2017)

4gsr said:


> I have a transit my dad used to use for leveling long lathe beds.  He used to level deep hole trepanning machines, which some of them had bed lengths of over 120 foot in length.  Most were in the 40 to 60 feet in length.  A transit can get a bed level level within a couple of thousandths in ten feet under the right conditions.  As mentioned, lasers are more common to use.  You still have a margin of error with either method used as well as how stable of an foundation you have for the machine.


The lathe that I mentioned was set for deep trepanning; had a bunch of big steady rests and high pressure coolant system and  had two carriages that the operator rode on with control panels; all its functions had been converted to CNC so the operator could control everything from either carriage; it had a power tailstock mover and powered tailstock quill; It was used on one job, that of machining giant "pins" that were seismic features of the new Bay Bridge in San Francisco Bay.


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## 4GSR (May 21, 2017)

I've seen pictures of a couple of the one's you are talking about.  They are monsters and hugh!  I one's we dealt with back then were set up to drill a maximum of- 4-3/4 hole size.  Most were set up to drill about 3" ID x 32 foot deep from both directions at the same time.  Any chance of sharing any pictures of them?


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## benmychree (May 21, 2017)

4gsr said:


> I've seen pictures of a couple of the one's you are talking about.  They are monsters and hugh!  I one's we dealt with back then were set up to drill a maximum of- 4-3/4 hole size.  Most were set up to drill about 3" ID x 32 foot deep from both directions at the same time.  Any chance of sharing any pictures of them?



I do not think that I have any pictures of the lathe; I was at the location in Napa, Ca. buying some machinery at the old Kaiser Steel plant where the contractor was leasing space to do the Bay Bridge job, which was hollow tube with about 4" wall thickness rolled up and sub arc welded, with sections of about 2" wall thickness in places, I was told that the thin sections were for seismic deformation; the completed length was about 60 ft, with stainless steel overlay in sections that was machined to a fine finish.  the site has been literally leveled and all the machinery either scrapped or sold.  The site looks forward to residential  and commercial development.
The big lathe was, I think used for production of marine tail shafting; I have seen a picture of a shop with a bunch of these lathes of various sizes, a shop doing one thing; trepanning.   Also I remember that in the middle of the bed there was a channel with two big square threaded screws that counter rotated to convey the chips out to the tail end of the machine to be loaded into scrap skips.  On these lathes, the bed must be more than twice the length of the work being trepanned.  The bed was made in sections and bolted together so as to be able to be produced in virtually any length and to be transported.  The ways were flat, and at least 12" wide; It may have been a Niles lathe, but I do not remember for sure; I think I was told that it dated from the early 1950s; odd I think, as there should have been a surplus of them from WW-2 production.


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## 4GSR (May 21, 2017)

There was indeed a surplus of these machines left over from WWII.  All of the one's My dad and I dealt with came from one of the several arsenals as well from the government cave up in Kansas.  I recall something about a Very large Niles boring lathe out on the west coast back around 1978 at my first job.  The man I worked for back then bought a "sub-bed" that ran parallel to the main machine.  The ways on that machine were about 4 foot across.  The bed on the main  machine were something like 8 foot across!  The swing was something like 12 foot!  Never saw pictures of it.  Could be the same machine your talking about?


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## benmychree (May 21, 2017)

4gsr said:


> There was indeed a surplus of these machines left over from WWII.  All of the one's My dad and I dealt with came from one of the several arsenals as well from the government cave up in Kansas.  I recall something about a Very large Niles boring lathe out on the west coast back around 1978 at my first job.  The man I worked for back then bought a "sub-bed" that ran parallel to the main machine.  The ways on that machine were about 4 foot across.  The bed on the main  machine were something like 8 foot across!  The swing was something like 12 foot!  Never saw pictures of it.  Could be the same machine your talking about?


I guess we will never know where it came from and where it went; a contractor bought it, retrofitted it in anticipation for the job, then bailed on the job and the contractor in Napa bought it and completed the job; he also bought a huge plate bending roll to roll the sections and succeeded in breaking several times, as I remember, the roller bearings seemed to be the weak point!  They finally completed the job and dissolved the business.


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## Bill Wardlow (May 25, 2017)

If this is a real mistake, I hope someone will tell me so: I have worried about bed flex and twist for as long as I've run a lathe. Maybe I've become obsessed! Here's the way I have held down the Jet 9X20 I recently purchased (used). I bolted the headstock end down solidly to the stand, on those weird riser blocks. Then I found a long bolt whose thread would get a good purchase in the stand and leave the bolthead about 2-3 inches  above the tail mount hole in the bed casting. Then I inserted a strong spring, a secondary automobile engine valve spring under the bolthead, with a washer of course. I isolated the bolt from the bed casting with a bit of rubber grommet. Then I tightened the bolt down enough to keep the tailstock end from walking around and vibrating (it didn't anyway under light load). Now I go to bed at night not worrying that my poor baby is warping as I sleep. Am I brilliant or a dummy?

Bill W


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## Bill Gruby (May 25, 2017)

Bill W. :

  I have had my Jet 9x20 for many years now. Bolted it down the way you did because the stand is sheet steel. I have never had to realign anything in all those years. You did good.

 "Billy G


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