Twist in my bed

Pevehouse said:
Hello all. I know there’s tons of info out there for this particular situation but I have kind of a unique situation I need advice for. I have an older 12x36 Enco lathe that I have been trying to level and get the twist out of. Problem is no matter what I do I can’t get it to level. It’s like the setup is too ridged. When I got the machine it was setup the way it is now. It has had a large heavy steel frame built around the actual lathe bench and I believe it’s what’s got me chasing my tail. I was thinking about taking the framing off and sitting the lathe bench on the floor, on leveling feet of coarse, so that the bed can twist the way I need it to. However that’s not going to be an easy task so I wanted to get some advice from some people that have felt with and knows a thing or two about how a bed reacts to certain stresses. Before I go through the task of lifting the lathe and resetting everything. Thanks in advance. I will add some photos of what we are dealing with.
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Pevehouse, I feel your pain. If that frame was installed without the bed being level then it is a contributing factor. When I received my PM1236 (new) through its travels and being mounted to a wood pallet, the bed was warped and it took me 3 or 4 months worth of patients to get it out because the bed needs to settle. Mine is mounted on the cabinet it came with and I have the leveling feet under that which I bought with the lathe. I wasn't making good progress until I put 150 pounds of lead in the cabinet on the corner that needed to drop. I then leveled it as best I could and backed the pressure off the corner with the lead in it ever so slightly to allow it to drop. After 2 or three weeks I put the level on it and adjusted it again in the same manner (rinse lather repeat) Once I had it level I adjusted the feet until the day I placed the level on it and it had not changed from the previous adjustment, it had reached equilibrium. I had a few tapered parts until it was level, into each life a little rain must fall; but now it cuts true.
 
Pevehouse said:
lol, I have tried that but it’s still in the back of my Mind. Not really knowing if it’s level. I have tried to level it on bedways and it does the exact same thing. I will say I am not familiar with any other methods such as the two collar test I keep hearing about. So is that how I can verify that it’s cutting straight?
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I used a machinist level, Accusize has a good one for a reasonable price on amazon. If you go to Abom79 on YouTube and go back in his archives he did a good video on (several actually) on how to properly use a machinist level and how to level a lathe.
 
verbotenwhisky said:
Pevehouse, I feel your pain. If that frame was installed without the bed being level then it is a contributing factor. When I received my PM1236 (new) through its travels and being mounted to a wood pallet, the bed was warped and it took me 3 or 4 months worth of patients to get it out because the bed needs to settle. Mine is mounted on the cabinet it came with and I have the leveling feet under that which I bought with the lathe. I wasn't making good progress until I put 150 pounds of lead in the cabinet on the corner that needed to drop. I then leveled it as best I could and backed the pressure off the corner with the lead in it ever so slightly to allow it to drop. After 2 or three weeks I put the level on it and adjusted it again in the same manner (rinse lather repeat) Once I had it level I adjusted the feet until the day I placed the level on it and it had not changed from the previous adjustment, it had reached equilibrium. I had a few tapered parts until it was level, into each life a little rain must fall; but now it cuts true.
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Sounds very familiar. Based on what I’m seeing and my gut feeling I think it’s worth at least removing the framing and sitting it on some good leveling feet on the bench itself. Just like what you are telling me. The way they framed it was a nice shot at trying to strengthen the cabinet but I don’t think it needed it. Also to make things worse they left the center part of the cabinet or bench , completely unsupported.The way it sits now, the bed needs to flex to be properly leveled and it can’t. At least that was my thinking. I could be wrong, that’s why I reached out to you guys. Thank you
 
Pevehouse said:
Sounds very familiar. Based on what I’m seeing and my gut feeling I think it’s worth at least removing the framing and sitting it on some good leveling feet on the bench itself. Just like what you are telling me. The way they framed it was a nice shot at trying to strengthen the cabinet but I don’t think it needed it. Also to make things worse they left the center part of the cabinet or bench , completely unsupported.The way it sits now, the bed needs to flex to be properly leveled and it can’t. At least that was my thinking. I could be wrong, that’s why I reached out to you guys. Thank you
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This is my setup, the yellow feet are the levelers and the piece between the cabinet ends is a sheet metal and the brake peddle, other than that the ends can flex independently.
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verbotenwhisky said:
This is my setup, the yellow feet are the levelers and the piece between the cabinet ends is a sheet metal and the brake peddle, other than that the ends can flex independently.
View attachment 478195
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That almost exactly how mine is setup. Minus the brake. Sheet metal in the center. I would like to keep the lathe attached to the bench partly due to the fact that I sealed the bed to the chip tray just in case I wanted to add flood coolant some day. A shim stuck in theee would defeat the purpose of sealing it up. So I would like to do it the way it was designed to be done. Exactly like yours is setup. Very nice setup by the way
 
verbotenwhisky said:
This is my setup, the yellow feet are the levelers and the piece between the cabinet ends is a sheet metal and the brake peddle, other than that the ends can flex independently.
View attachment 478195
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This is my setup. I don’t have a place there in the center close to the headstock end to mount 4 pads so I may have to settle for some jacks there but I would be good with that as long as the machine was comfortable if you know what I mean
 

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I'd do a two collar test and see how far out it is. The level doesn't mean much IMHO, see how much of a taper it cuts and go from there.

John
 
Pevehouse said:
This is my setup. I don’t have a place there in the center close to the headstock end to mount 4 pads so I may have to settle for some jacks there but I would be good with that as long as the machine was comfortable if you know what I mean
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That doesn't look bad at all, that is a nice machine. I like the way your machine sets up high over the chip tray.

Just my observations:

Is the frame with the feet on it connecting across beneath the lathe? I had envisioned a structural steel skid/pallet under it. If not you might be better off to add another angle below the opposite side of the head stock cabinet for 2 more levelers to add some support on that end. Having the lathe supported from the extreme ends of the cabinet may be your issue because you are trying to twist the entire lathe. The more I stare at it I think also (if possible) you could move the feet on the tail Stock end in to center it on that cabinet might be an improvement as well.

When we design supports for equipment at work we layout the point that the sub-structure below the equipment is below the mounting points of the equipment so we do not add any moments of stress to either, we purposely set it up to transfer the load as directly as possible to the foundation.

If you look at mine the tail stock end levelers are below the lathes tail stock foot and the middle levelers are below the point where the head stock and bed join, when I adjust those 4 I am acting on the bed and I work the outer set below the head stock in unison with the other 2 under at the head stock.
 
verbotenwhisky said:
That doesn't look bad at all, that is a nice machine. I like the way your machine sets up high over the chip tray.

Just my observations:

Is the frame with the feet on it connecting across beneath the lathe? I had envisioned a structural steel skid/pallet under it. If not you might be better off to add another angle below the opposite side of the head stock cabinet for 2 more levelers to add some support on that end. Having the lathe supported from the extreme ends of the cabinet may be your issue because you are trying to twist the entire lathe. The more I stare at it I think also (if possible) you could move the feet on the tail Stock end in to center it on that cabinet might be an improvement as well.

When we design supports for equipment at work we layout the point that the sub-structure below the equipment is below the mounting points of the equipment so we do not add any moments of stress to either, we purposely set it up to transfer the load as directly as possible to the foundation.

If you look at mine the tail stock end levelers are below the lathes tail stock foot and the middle levelers are below the point where the head stock and bed join, when I adjust those 4 I am acting on the bed and I work the outer set below the head stock in unison with the other 2 under at the head stock.
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That makes perfect sense. As it sits right now I would almost expect the middle of the lathe to be bowed or sagging in the middle. There’s no support underneath. Just the rail that runs along the back of the machine. I have a way to lift the machine, so i can do whatever needs to be done. I just was kind of wanting some advise on how to go about it. I just figured maybe removing the frame all together and sitting the bench on levelers may be the way to go about it. If it is indeed acting on the extreme ends of the machine, like it appears to be. That could explain a lot. If for just my peace of mind, it would make me feel better about the set up knowing it was a little better braced up from underneath. I will do some digging on the two collar test as well. I feel the best order is to better support it in hopes that that would help with the leveling issue I’m having. Then move on to the testing and correcting of tail stock and headstock alignment. That should cover all the bases
 
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