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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Twist in my bed
- Thread starter Pevehouse
- Start date
- Joined
- Aug 19, 2023
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- 501
You note you have a "twist" in the bed, yet there are still a couple unanswered questions...
How much is the twist?
Is the twist closer to the headstock, in the middle of the bedway or closer to the tailstock?
Is the twist towards the front of the lathe or away towards the rear of the bedway?
How are you measuring the level and is what you are using to measure the twist a proven accurate tool (level)
How much is the twist?
Is the twist closer to the headstock, in the middle of the bedway or closer to the tailstock?
Is the twist towards the front of the lathe or away towards the rear of the bedway?
How are you measuring the level and is what you are using to measure the twist a proven accurate tool (level)
I think I would try removing the twist at the lathe rather than the stand. It's going to be bolted down to the stand, so you can pull those and adjust. When I got my lathe, I made some leveling jacks that I put between the bench and the lathe. They work great to make it easy to adjust and remove that sort of issue. Here's a pic of what they look like.
Use the level on the bench so round stock doesn't roll off too easy. Then adjust twist on the bed directly. Measure twist with the 2 collar test, not a level.
Use the level on the bench so round stock doesn't roll off too easy. Then adjust twist on the bed directly. Measure twist with the 2 collar test, not a level.
- Joined
- Feb 1, 2015
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A common problem when leveling a lathe on a stand is that the stand will twist as well. Applying a correction will affect both and not have a great an effect on the bead level as calculated. How a correction is apportioned depends on the relative rigidity of the stand and the lathe.
In an ideal situation. a bench lathe will be mounted on a very rigid bench that is securely seated on the floor, My G0602 lathe is mounted on a steel bench constructed from #", 4", and 7" channel. When I was initially trying to change the twist, there was enough twist introduced to the bench that it would lift one foot off the floor. I added another foot at the tailstock and used to two outer tailstock feet as stabilizers so that I now had a three point mount. Three points determine a plane so that any effort in leveling the bench is not causing a twist and any further corrections are accomplished between the lathe and the bench.
I still get some twisting of the bench when adding or removing shims but at least now it's consistent and stable. As @ttabbal stated, leveling is the first step. The final step is accomplished with either the two collar test or the RDM method. My preference is the RDM method followed by verification using the two collar method.
In an ideal situation. a bench lathe will be mounted on a very rigid bench that is securely seated on the floor, My G0602 lathe is mounted on a steel bench constructed from #", 4", and 7" channel. When I was initially trying to change the twist, there was enough twist introduced to the bench that it would lift one foot off the floor. I added another foot at the tailstock and used to two outer tailstock feet as stabilizers so that I now had a three point mount. Three points determine a plane so that any effort in leveling the bench is not causing a twist and any further corrections are accomplished between the lathe and the bench.
I still get some twisting of the bench when adding or removing shims but at least now it's consistent and stable. As @ttabbal stated, leveling is the first step. The final step is accomplished with either the two collar test or the RDM method. My preference is the RDM method followed by verification using the two collar method.
Thanks to everyone that has responded. I am measuring with a starrett 15” master level, sitting on the cross slide, traversing the carriage back and forth. I just cannot seem to get the thing to level both at the headstock and the tail stock . I will level one end, then move to the other and level it and it in turn throws the other end back off
- Joined
- Aug 19, 2023
- Messages
- 501
Daft question, Have you tried actually measuring on the bed itself, rather than on the cross slide?
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?