As You mentioned, that is a wooden bench the lathe is sitting on. It flexes. I think somebody said it already but the most important thing in leveling is to get the twist out of the bed. Or to be more accurate, manipulate the twist in a way that the lathe is cutting straight. These small lathes should be mounted on a rigid base. When I had mine, it was sitting on a steel plate of 15 mm, about half an inch, thick. That made all the difference in rigidity. That plate was heavy enough so thatthere was no need to bolt it to the wooden table it was sitting on.
Hi folks. A level bed is not really necessary although it can help with setting up some jobs. There are lots of lathes made with forward slanting beds to aid access for example. What IS needed is the right amount of twist in the bed so that the lathe does indeed turn parallel, and that is best achieved by the extensively documented business of making test cuts. After that, get the tailstock accurately aligned. If still having trouble with finish quality check for unnecessary play on the carriage, cross slide, and tool post. Also crucially check your tooling. A sharp point to the tool is often the cause, it needs to have a very slight but perceptible radius. If a beginner have a read of the excellent books by the late George Thomas and you will improve your work considerably. George was the Guru's guru for model engineering and he had an easy style in getting it across. BobUK.
Mark thanks for the Vid. Really useful. QQ? At the start, you calibrated the machinist level. Is that being done from the floor upon which the lathe is standing? I only ask as I may need to do the same thing and wanted to check if its ok ? Kind Regards Stephen
Hi Stephen, Thanks for the feedback and question. I calibrated the level on a different bench, but it won't matter where it's calibrated (as long as it not too far away!). Cheers Mark
Mark, what size of fasteners did you use to attach your lathe to the bench. I will take delivery of a WM250V in two weeks and I would like to have the fasteners ready. Thank you for the levelling video which will be very useful when I set my machine up.
Hi Mark, I don't know yet. I'll run some test cuts today and let you know. I don't think levelling will make a significant impact on the finish, rather it will be more about consistent results (diameter) along the longitudinal axis. I've also been struggling to get the tail stock aligned, which should now be easier. Cheers, Mark.
@@markshomeengineering5243Yes this video was from 3 yrs ago, new to me though. Many make the error of leveling across the bare lathe bed. In theory that should work fine. However, you don't turn anything using that bare bed. It's the carriage and everything above it that's being used. A much better and more representative job is done by placing the level (front - back) on the top of the cross or top slide and then running the carriage left - right. Due to the height of the tool tip above the bed, there's a magnification factor of any twist in the bed. What happens is during longitudinal turning and with any twist in the lathe bed, that twist will slowly roll the tool tip either inwards or outwards depending on the direction of twist. It's that effect that's causing the taper variation. A lathe bed with lets say .001" / .025 mm twist across the ways will show more than that as a tapered part along it's length just due to that vertical elevation of the tool tip above the bed. And the wider your lathe bed is, the more magnification of any bed error you'll see under those cutting conditions. How you did it across the bare bed would be fine for your initial rough leveling. I would then do a secondary double check of the lathe bed squareness with the level placed on the cross, or a bit better in my opinion the top slide. With the bed finally in a known and correct square condition you then adjust the tail stock to center it's Morse Taper bore to the head stocks C/L. Again that would be your initial starting point for aligning the lathe. Any further accuracy checks and alignment adjustments need to be done only after the bed is in a known to be true condition. It also needs to be understood that leveling the bed is a static condition. It can't and won't provide a true indication of what the lathes parallel turning accuracy really is. So at that point I always do a proper parallel turning test with the largest diameter and longest bar of steel I have handy. And it's always done between centers to remove any possible effects from radial or axial inaccuracy a chuck may have. Properly done, the best chuck or collet in the world still can't replicate the accuracy and repeatability that simple between centers turning can easily do. It's why the most accurate radial grinding done today is still performed using dead centers. I also don't use the head stocks taper or dead center most lathes will come with. If your measurement equipment has enough accuracy, you can detect at least some minor amounts of inaccuracy on that dead center point. Instead I use a short piece of 1" - 1.5" / 25 - 35 mm diameter material held in any chuck or collet and turn my own 60 degree point on it. As long as it's not removed and replaced, that point is known to be completely concentric to the head stock and it's bearings. A dynamic parallel cutting test will almost always show some very minor bed twist adjusting is still required to get the lathe to turn truly parallel end to end. What that last adjustment does is help compensate for the inevitable deflections that occur within the lathe under those cutting loads. Most forum posts and YT videos only go as far as only mentioning lathe leveling and mill head tramming. It's vastly more involved than that. Doctor Georg Schlesinger literally wrote the book about machine tool alignment. There's a free online PDF of it found here. pearl-hifi.com/06_Lit_Archive/14_Books_Tech_Papers/Schlesinger_Georg/Testing_Machine_Tools.pdf Every half decent machine tool manufacturer around the world including the cnc machine tool builders base there certificates of accuracy in one way or another on his work. Some of it may be modified or added to for the multi axis equipment, but the basic test measurements for machine alignment are still done in exactly the same way.
Hi Mark, Its good to follow your setting up as I too got my 250v around the same time, so any references to the model have been useful for understanding and improvements across RUclips. I notice you have a carriage stop and this is something I want to make, I am quite a novice and have upgraded from a mini lathe which had a shop bought stop. Any help on this would be grateful there are so many vids out there but for other older or U.S. lathes. Russell
Hi Russel, my stop was knocked together in about 20 minutes and given it's quality (or lack of) it's not something I really want to shout about :-) It's basiclly a couple of lumps of bms, one has a crude "v" milled into it, with a couple of holes drilled through to align to the other lump, which is drilled/tapped accordingly. This allows the whole lot to be moved along the bed and clamped accordingly. I've then drilled and tapped aother hole for a bolt, with a locknut, to act as a stop on the carriage. It really is that simple.
@@markshomeengineering5243 Hi Mark Thanks for replying, I have literally just finished making one!, Took me most of the afternoon but it seemed to work. I've gone as far as adding DRO and made it really difficult to access the carriage lock so replaced the allen bolt for a standard bolt that sits proud and I can just get an open spanner on it. I liked your new block you made, a little too precise for my current machining skills, although i'm on my 3rd Stuart models steam project, so far so good. Majority was made on my smaller mini lathe! So a new 7.5 inch fly wheel was done on the Warco I do like the feel of it and it capability for my hobby to 'scale up'.
As You mentioned, that is a wooden bench the lathe is sitting on. It flexes.
I think somebody said it already but the most important thing in leveling is to get the twist out of the bed. Or to be more accurate, manipulate the twist in a way that the lathe is cutting straight.
These small lathes should be mounted on a rigid base. When I had mine, it was sitting on a steel plate of 15 mm, about half an inch, thick. That made all the difference in rigidity. That plate was heavy enough so thatthere was no need to bolt it to the wooden table it was sitting on.
Hi folks. A level bed is not really necessary although it can help with setting up some jobs. There are lots of lathes made with forward slanting beds to aid access for example. What IS needed is the right amount of twist in the bed so that the lathe does indeed turn parallel, and that is best achieved by the extensively documented business of making test cuts. After that, get the tailstock accurately aligned. If still having trouble with finish quality check for unnecessary play on the carriage, cross slide, and tool post. Also crucially check your tooling. A sharp point to the tool is often the cause, it needs to have a very slight but perceptible radius. If a beginner have a read of the excellent books by the late George Thomas and you will improve your work considerably. George was the Guru's guru for model engineering and he had an easy style in getting it across. BobUK.
Mark thanks for the Vid. Really useful. QQ? At the start, you calibrated the machinist level. Is that being done from the floor upon which the lathe is standing? I only ask as I may need to do the same thing and wanted to check if its ok ? Kind Regards Stephen
Hi Stephen,
Thanks for the feedback and question.
I calibrated the level on a different bench, but it won't matter where it's calibrated (as long as it not too far away!).
Cheers Mark
Mark, what size of fasteners did you use to attach your lathe to the bench. I will take delivery of a WM250V in two weeks and I would like to have the fasteners ready. Thank you for the levelling video which will be very useful when I set my machine up.
Hi Philip,
I used 10mm studding, cut to length as required.
Good luck with your machine when it arrives.
Mark
@@markshomeengineering5243 thanks Mark.
Good info and glad you’re doing a voice over but if the music was to go it might help. Also any revenue from RUclips might get to you!
Thanks for the feedback Karl - you're not the only one to comment on the music :-)
As for the revenue, that's of no interest to me.
Cheers
Mark
Great, clear and informative videos, am looking at one of these lathes myself. Did your levelling improve your finishing cuts?
Hi Mark,
I don't know yet. I'll run some test cuts today and let you know.
I don't think levelling will make a significant impact on the finish, rather it will be more about consistent results (diameter) along the longitudinal axis. I've also been struggling to get the tail stock aligned, which should now be easier.
Cheers, Mark.
Hope you’ll do a vid on that too!
@@markshomeengineering5243Yes this video was from 3 yrs ago, new to me though. Many make the error of leveling across the bare lathe bed. In theory that should work fine. However, you don't turn anything using that bare bed. It's the carriage and everything above it that's being used. A much better and more representative job is done by placing the level (front - back) on the top of the cross or top slide and then running the carriage left - right. Due to the height of the tool tip above the bed, there's a magnification factor of any twist in the bed. What happens is during longitudinal turning and with any twist in the lathe bed, that twist will slowly roll the tool tip either inwards or outwards depending on the direction of twist. It's that effect that's causing the taper variation. A lathe bed with lets say .001" / .025 mm twist across the ways will show more than that as a tapered part along it's length just due to that vertical elevation of the tool tip above the bed. And the wider your lathe bed is, the more magnification of any bed error you'll see under those cutting conditions.
How you did it across the bare bed would be fine for your initial rough leveling. I would then do a secondary double check of the lathe bed squareness with the level placed on the cross, or a bit better in my opinion the top slide. With the bed finally in a known and correct square condition you then adjust the tail stock to center it's Morse Taper bore to the head stocks C/L. Again that would be your initial starting point for aligning the lathe. Any further accuracy checks and alignment adjustments need to be done only after the bed is in a known to be true condition.
It also needs to be understood that leveling the bed is a static condition. It can't and won't provide a true indication of what the lathes parallel turning accuracy really is. So at that point I always do a proper parallel turning test with the largest diameter and longest bar of steel I have handy. And it's always done between centers to remove any possible effects from radial or axial inaccuracy a chuck may have. Properly done, the best chuck or collet in the world still can't replicate the accuracy and repeatability that simple between centers turning can easily do. It's why the most accurate radial grinding done today is still performed using dead centers. I also don't use the head stocks taper or dead center most lathes will come with. If your measurement equipment has enough accuracy, you can detect at least some minor amounts of inaccuracy on that dead center point. Instead I use a short piece of 1" - 1.5" / 25 - 35 mm diameter material held in any chuck or collet and turn my own 60 degree point on it. As long as it's not removed and replaced, that point is known to be completely concentric to the head stock and it's bearings. A dynamic parallel cutting test will almost always show some very minor bed twist adjusting is still required to get the lathe to turn truly parallel end to end. What that last adjustment does is help compensate for the inevitable deflections that occur within the lathe under those cutting loads.
Most forum posts and YT videos only go as far as only mentioning lathe leveling and mill head tramming. It's vastly more involved than that. Doctor Georg Schlesinger literally wrote the book about machine tool alignment. There's a free online PDF of it found here. pearl-hifi.com/06_Lit_Archive/14_Books_Tech_Papers/Schlesinger_Georg/Testing_Machine_Tools.pdf Every half decent machine tool manufacturer around the world including the cnc machine tool builders base there certificates of accuracy in one way or another on his work. Some of it may be modified or added to for the multi axis equipment, but the basic test measurements for machine alignment are still done in exactly the same way.
Hi Mark,
Its good to follow your setting up as I too got my 250v around the same time, so any references to the model have been useful for understanding and improvements across RUclips.
I notice you have a carriage stop and this is something I want to make, I am quite a novice and have upgraded from a mini lathe which had a shop bought stop. Any help on this would be grateful there are so many vids out there but for other older or U.S. lathes.
Russell
Hi Russel, my stop was knocked together in about 20 minutes and given it's quality (or lack of) it's not something I really want to shout about :-)
It's basiclly a couple of lumps of bms, one has a crude "v" milled into it, with a couple of holes drilled through to align to the other lump, which is drilled/tapped accordingly. This allows the whole lot to be moved along the bed and clamped accordingly.
I've then drilled and tapped aother hole for a bolt, with a locknut, to act as a stop on the carriage. It really is that simple.
@@markshomeengineering5243
Hi Mark Thanks for replying, I have literally just finished making one!, Took me most of the afternoon but it seemed to work. I've gone as far as adding DRO and made it really difficult to access the carriage lock so replaced the allen bolt for a standard bolt that sits proud and I can just get an open spanner on it.
I liked your new block you made, a little too precise for my current machining skills, although i'm on my 3rd Stuart models steam project, so far so good. Majority was made on my smaller mini lathe! So a new 7.5 inch fly wheel was done on the Warco
I do like the feel of it and it capability for my hobby to 'scale up'.
@@russellwhittle5162 Awesome! and well done :-)