# MX210 D/S MT5 8x16 lathe review



## greenail

I bought a bit of an oddball lathe and wanted to share my thoughts in case someone else is considering the machine.  This is essentially the same as the WM210 WM180, MX210, and G0678 other than the MT5 difference.

This is very close to the standard 200x400 or 8x16 but instead of the MT3 chuck it has an MT5.  The main implication for this change is that the drive gear on the spindle is 56 tooth vs 40 tooth and the pulley setup will also be more snug though it is unclear what belts are needed.  I just broke a belt and I don't really trust the manual the machine came with since the threading gear charts are all wrong.  The manual says 5M360 but that seems to be a very uncommon belt type.  The grizzly manual for this machine says it needs 5M365 and 5M375 belts.  I asked the seller on ebay and they sent me a picture of a 5M375 belt.

When I received the machine it was clearly rolling around the whole trip with a single bolt securing it.  It took a big dent in the front cover, bent the gear cover bolt, as well as a few other issues.  I should have refused shipment.  The seller has been very responsive and claims to be sending replacement parts for everything.

I was able to get the machine started and running but it was filthy with grinding dust and needed to be fully stripped down and cleaned.   It did not have cosmoline on it, rather a snotty gelatin type goop which was much easier to clean than the cosmoline.

The first problem I discovered was that the hold downs for the ways did not have any counter adjusting grub screws and looked like they were machined with a dull carp.  I ended up squaring and milling them on my mill and tapping 3 m5 grub screws so I could adjust the fit to the ways.  Without this adjustment there was at least .125" of slop rocking the cross slide.

The next problem was the carrage lock.  It was drilled and tapped cocked around 10 degrees off.  I've abandoned the factory setup and need to do a custom carriage lock later.

Many of the castings on the cross slide and compound were extreemly rough.  They required heavy deburring, some needed time on the milling machine, and they needed lapping.  I ended up installing a OXA quick change tool post and did the compound through hole mod to allow me to adjust the angle of the compound without unscrewing it 90% of the way.

The tailstock was about .25" off and locked up so it had to be fully stripped down.  It turned out there was not enough room for adjustment and it required some filing and milling to square up.  I also needed to shim it to get the height correct.  Finally the locking mechanism required adjustment to get working properly.

I believe the reason I broke the belt was that it was over tight.  I was unable to change the belt without going into the back of the lathe to unfasten the bolt on the inside of the electronics cover.  There are some blogs on ways to fix this so you can change the speed without this extra work.  This seems like a pretty intensive mod and I didn't really need the speed yet so I had put it off.  Then my belt broke.

The final mod I did was to put a bearing on the compound slide.  The compound is impossible to turn without binding.   It is very hard to adjust it without lapping due to the extremely poor milling.  Combining this with the very loos bushing fit and you will find it binds on any attempt to turn the compound with one hand.  My bearing fix is pretty much a hack and I'm going to redo it when I have some spare time.  The machine really is abysmal to use without the angle mod and something to make adjusting the compound easier.

So net net it was a lot of work but I also learned and know feel pretty confident with how the machine works and I have a better sense for what features I would appreciate on a lathe in the future.  I do not think I would make this purchase again.  As with most things you get what you pay for.


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## greenail

Another thing to note is that while the spindle bore is 38mm, the chucks that came with it are less.  It came with a 3 jaw and 4 jaw self centering chuck.  I just put the 4 jaw on for the first time and had assumed it was an independent jaw.  It is not.  I'm not sure why you'd need both a 3 jaw and 4 jaw self centering unless you needed to do lots of triangular stock!  the 4 jaw seems to repeat much better though.


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## pistonbroke

greenail said:


> Another thing to note is that while the spindle bore is 38mm, the chucks that came with it are less.  It came with a 3 jaw and 4 jaw self centering chuck.  I just put the 4 jaw on for the first time and had assumed it was an independent jaw.  It is not.  I'm not sure why you'd need both a 3 jaw and 4 jaw self centering unless you needed to do lots of triangular stock!  the 4 jaw seems to repeat much better though.


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## pistonbroke

Hi all,
And especially to Greenail above, because you're probably about 3 months ahead of me and you've just scared me to death with your account of your purchase!
I've become very interested in mini lathes since I saw what's the first 8''x16'' offerings on ebay in the u.k.(via) a German importer. Specifically  the 38mm up  the spout makes the deal  for me, but not if the piece won't go through the chuck. So on reading further from you, I notice that you're looking for a larger chuck. So does a 125mm chuck allow a 38mm shaft through?
Thanks so much in advance for any info on the subject.
 A quick further question if I may...have you started machining in earnest with your new purchase yet and if you have...any thoughts on how it handles mild and alloy steels, particularly screw cutting?

This is my first ever journey in to hobby engineering so apologies for my lack of any kind of background knowledge.
Fingers crossed things will improve.

Cheers Pb


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## greenail

pistonbroke said:


> Hi all,
> 
> I've become very interested in mini lathes since I saw what's the first 8''x16'' offerings on ebay in the u.k.(via) a German importer. Specifically  the 38mm up  the spout makes the deal  for me, but not if the piece won't go through the chuck. So on reading further from you, I notice that you're looking for a larger chuck. So does a 125mm chuck allow a 38mm shaft through?



I ended up winning a bid for a 6" (150mm) Chin Yu chuck with an MT5 taper.  The lathe is listed as having a 5MT but it does not fit what I was shipped from my ebay buy.  I have no other known 5MT tool.  

The ID of the 5" 4 jaw self centering chuck it came with is ~ 30mm, the ID of the 6" ebay chuck is ~41mm, the ID of the lathe spindle tube at the gear end was measured with calipers at 38.21mm.  I did not pop off the chuck to measure the business end.  The "5MT" chuck adapter fat part was 38.1.  Wikipedia says the fat end of the 5MT taper should be 44.399mm.  I think the ebay part is not 5mt.



pistonbroke said:


> A quick further question if I may...have you started machining in earnest with your new purchase yet and if you have...any thoughts on how it handles mild and alloy steels, particularly screw cutting?



I had lots of early experience with some old and very large woodworking machinery and I am somewhat comfortable working on machines in general from that experience.  I have very very limited machining experience.  I have a grizzly version of the seig X2.7 mill and have used the X2 mill for comparison.  I have no other metal lathe to compare.

When I got the lathe it cut like crap.  It either was sloppy as hell or it was very difficult to move.  What I mean by crap is it would leave strings of variable height.  This could have been due to my tool setup also.  I have not yet made a toolheight gauge.

Now I'm able to operate it and get a decent surface finish with honed HSS.  the smaller diameter carbide cuts pretty well but I ended up printing my own change gears on my 3d printer to reduce the feed speed and it is hard to tell how much of an impact that had vs the other improvements I made.  It does require some polishing which I'm typically doing with 320grit and some jewlers rouge on a leather strop.

The biggest rigidity/cut quality improvements:

1. re-machine the saddle bars and add grub screws.
2. add bearing to top/compound slide.
3. lap cross slide and top slide.
4. adjust tailstock nut position

Biggest usability improvements

1. access holes for top/compound slide rotation clamp screws
2. bearing for top/compound slide
3. lapping

The surface finish from top to bottom

1. aluminum T6 3/4 round bar cut after adjustment
2. random bolt used to set tailstock  and test first cuts.
3. random rod cut after some adjustment







What's a good way to compare my results with somethng else?


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## hman

greenail said:


> This could have been due to my tool setup also.  I have not yet made a toolheight gauge.


Grab a thin steel ruler or a single feeler gauge.  Hold it lightly between the tip of the tool and the workpiece.  If it stands vertically, you're on center.  If it tips away from you at the top, the tool is set too high.  If it tips toward you, the tool is set too low.  Back off the cross slide, adjust the tool height, and try again.  This is the "old school"/traditional method of setting tool height, has worked for umptyleven years.  Maybe not as fast or convenient as a modern dedicated height setter, but requires minimal gadgetry and gives reliable results.


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## greenail

hman said:


> Grab a thin steel ruler or a single feeler gauge.  Hold it lightly between the tip of the tool and the workpiece.  If it stands vertically, you're on center.  If it tips away from you at the top, the tool is set too high.  If it tips toward you, the tool is set too low.  Back off the cross slide, adjust the tool height, and try again.  This is the "old school"/traditional method of setting tool height, has worked for umptyleven years.  Maybe not as fast or convenient as a modern dedicated height setter, but requires minimal gadgetry and gives reliable results.



Yup, good method but ppl should keep in mind the diameter of the stock used with this method has an impact on it's accuracy.


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## greenail

i've been trying to do some threading and I don't know why but I can't seem to get anything to work out but the first thread i tried for a 12mm standard od.

the manual is clearly not accurate as the headstock has a gear with 56 teeth on it.  The gear cover has a chart on it but i can't fit the combination for 0.5mm pitch on the banjo.  really disappointed in this lathe.

I also discovered the headstock was out about .1m over 50mm.  there are only 2 M8 screws holding the headstock down and it was  misaligned by quite a lot based on the bolt hole locations.   

the last thing i tried was a straight combination of 56 80 30 60 which should produce .35 turns on the leadscrew but the output was closer to 1.75  based on my threading gauge.  I can't find a calculator that works for this headstock gear size...


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## Mr. Science

out of curiosity - is this the same one? sounds a lot like mine .... Morse 5 taper and 1.5" pass through etc


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## jrjr

I just picked up one of these. Has anyone figured out what MT fits the head stock spindle?


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## greenail

it says mt5 but I tried the only mt5 thing I had and it didn't fit.  I didn't spend much time on it though and put the chuck back on.  It is strange that mine came with 3 jaw and a 4 jaw self centering chucks.


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## jrjr

Thanks, mine only came with the 5" 3 jaw. I was going to buy something mt5 but seems a waste to buy something to test fit if it might not fit.


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## jrjr

Anyone else know if mt5 actually fits?


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## greenail

I just made a block to replace the compound slide and I still can't seem to get any rigidity.  my little 7x10 lathe is much more rigid!  I'm planning on talking the spindle out to see if it in fact actually has roller bearings.  All the chatter when parting seems to be coming from the headstock at this point so I'm not sure what else to do .  Worst tool I've purchased in a while.


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## greenail

so i ended up pulling the spindle.  There was grinding dust thick in the bearing seats.  The wear patter on the roller bearings was top on one half, bottom on the other half.  This seems to indicate there was something pushing them out of square.  The rear of the boar where the back of the bearing seated had huge burrs.  Every surface stacked up on the spindle had burrs, the gear, the spacer with the magnets, the pulley and both of the nuts.  

I figured I had nothing to loose by re-assembling it after deburring everything.  I used a die grinder stone to deburr the bearing boar seats by hand.  I couldn't really do much about the inside where the seals were.  it was like 60 grit sandpaper on the inside of the headstock.  I "lapped' all the components with 320 grit on a surface plate.  I chucked some of them up in my other lathe to deburr some edges.  The seals actually were not that bad, too bad they don't help squaring anything.  I used a chunk of 1.5" aluminum to tap out the bearing races and I cleaned them up with all the other parts in the ultrasonic cleaner.  The rear bearing got dropped on the floor and about 3 oz of chips were on there when I picked it up so I ended up putting that in the cleaner also.  All i had was white lithium grease so I packed that in the rear bearing and reassembled everything.  I also noticed that the bearing races had to be tapped into the start of the bore but they spun freely by hand when fully seated in the bore.  This made me think it could have been one of the sources of chatter.  I added quite a bit of preload (figuring I had nothing to lose).   I ran it for about 10 minutes and it didn't get warm or hot.

The rebuild seems to have helped though I'm not sure what had the most impact.  I did a test part on steel and I was able to feed it without chatter.  I have about 0.3mm of taper over 150mm which isn't great and i'm not sure how to fix that.  the milling on the bottom of the headstock was an awfull mess.  the casting was very pourus and felt like velcro to the finger.  I stoned it down and knocked off some of the really bad high spots but it still had some teeter/twist.  It was also odd that I preloaded the bearings before i put the headstock back on the bed.  When I tightened it to the bed I ended up needing to add more preload so I'm assuming the twist was somewhat straightened and relieved some stress on the bearings.  not really sure but it wasn't exactly a scraped surface.  A file may have done a better job actually.

I think my HF7x10 lathe is actually still more rigid without the roller bearings or larger bed...  The only thing good about this lathe so far is the 1.5" spindle bore and the chucks it came with, though it still strikes me odd that it came with both a 3 and 4 jaw self centering.  I bought a 6" independent 4 jaw but it's mt5 taper back plate doesn't fit and I havn't bothered to make a new back plate for it yet.


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## Tolerent

Many questions:

First, I see the Harbor freight 7x10 mentioned a few times above. It's locally about 570 with me thinking I can use their 20% discount coupon to put it in the price range of an ebay competitor. It seems none of the mini lathes anywhere have 4 star plus reviews. Is this more because they are nearly all poorly built or because they are mostly bought by people not prepared for the ride or is it because I am looking in the sub $1k price range? 

Is the HF 7x10 better than the $70 cheaper HF 7x12 available only online?

I see a few members sharing what appear to be hands on experience with the WM210V. I really am drawn to the 1.5" or 38mm Spindle bore. Still I see a lot of comments regarding runout or alignment problems. Is this the go to budget lathe for spindle bore > 1"? 

Is the WM210V a good choice or should I be looking for a more painful acquisition with expectations of a more pleasant future?


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## greenail

Tolerent said:


> Many questions:
> 
> First, I see the Harbor freight 7x10 mentioned a few times above. It's locally about 570 with me thinking I can use their 20% discount coupon to put it in the price range of an ebay competitor. It seems none of the mini lathes anywhere have 4 star plus reviews. Is this more because they are nearly all poorly built or because they are mostly bought by people not prepared for the ride or is it because I am looking in the sub $1k price range?
> 
> Is the HF 7x10 better than the $70 cheaper HF 7x12 available only online?
> 
> I see a few members sharing what appear to be hands on experience with the WM210V. I really am drawn to the 1.5" or 38mm Spindle bore. Still I see a lot of comments regarding runout or alignment problems. Is this the go to budget lathe for spindle bore > 1"?
> 
> Is the WM210V a good choice or should I be looking for a more painful acquisition with expectations of a more pleasant future?



It really comes down to how you want to spend your time and how you value your time.  Plenty to learn with this "kit" but if you don't want to fight the machine all the time I'd pick something else.  If you value your time at say $50/hour then this is a real money pit.  I bet I have 20 hours into mine.  Something as simple as changing the speed can be a whole project since you have to take the back panel off to access the screw for the pulley...  The banjo doesn't actually work for most of the metric threading pitches I needed.  I've detailed most of the problems i've had but I'm sure I forgot a few hours of miscellaneous chores I didn't really want to deal with.

All that said the 7x10 lathe isn't exactly a cure.  Mine was an older model and I think I got lucky both on the price and the chuck which has 0.01mm runout.  I converted it to CNC and got rid of the compound.  I'm not sure i'd want to use it with the compound since it is very hard to get tuned in and reduces rigidity quite a lot.  I also replaced the motor.

i wish I had experience with precision matthews, they seem to get good reviews but I have not set one up so I can't compare.


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## bogguey

greenail said:


> I bought a bit of an oddball lathe and wanted to share my thoughts in case someone else is considering the machine.  This is essentially the same as the WM210 WM180, MX210, and G0678 other than the MT5 difference.
> 
> This is very close to the standard 200x400 or 8x16 but instead of the MT3 chuck it has an MT5.  The main implication for this change is that the drive gear on the spindle is 56 tooth vs 40 tooth and the pulley setup will also be more snug though it is unclear what belts are needed.  I just broke a belt and I don't really trust the manual the machine came with since the threading gear charts are all wrong.  The manual says 5M360 but that seems to be a very uncommon belt type.  The grizzly manual for this machine says it needs 5M365 and 5M375 belts.  I asked the seller on ebay and they sent me a picture of a 5M375 belt.
> 
> When I received the machine it was clearly rolling around the whole trip with a single bolt securing it.  It took a big dent in the front cover, bent the gear cover bolt, as well as a few other issues.  I should have refused shipment.  The seller has been very responsive and claims to be sending replacement parts for everything.
> 
> I was able to get the machine started and running but it was filthy with grinding dust and needed to be fully stripped down and cleaned.   It did not have cosmoline on it, rather a snotty gelatin type goop which was much easier to clean than the cosmoline.
> 
> The first problem I discovered was that the hold downs for the ways did not have any counter adjusting grub screws and looked like they were machined with a dull carp.  I ended up squaring and milling them on my mill and tapping 3 m5 grub screws so I could adjust the fit to the ways.  Without this adjustment there was at least .125" of slop rocking the cross slide.
> 
> The next problem was the carrage lock.  It was drilled and tapped cocked around 10 degrees off.  I've abandoned the factory setup and need to do a custom carriage lock later.
> 
> Many of the castings on the cross slide and compound were extreemly rough.  They required heavy deburring, some needed time on the milling machine, and they needed lapping.  I ended up installing a OXA quick change tool post and did the compound through hole mod to allow me to adjust the angle of the compound without unscrewing it 90% of the way.
> 
> The tailstock was about .25" off and locked up so it had to be fully stripped down.  It turned out there was not enough room for adjustment and it required some filing and milling to square up.  I also needed to shim it to get the height correct.  Finally the locking mechanism required adjustment to get working properly.
> 
> I believe the reason I broke the belt was that it was over tight.  I was unable to change the belt without going into the back of the lathe to unfasten the bolt on the inside of the electronics cover.  There are some blogs on ways to fix this so you can change the speed without this extra work.  This seems like a pretty intensive mod and I didn't really need the speed yet so I had put it off.  Then my belt broke.
> 
> The final mod I did was to put a bearing on the compound slide.  The compound is impossible to turn without binding.   It is very hard to adjust it without lapping due to the extremely poor milling.  Combining this with the very loos bushing fit and you will find it binds on any attempt to turn the compound with one hand.  My bearing fix is pretty much a hack and I'm going to redo it when I have some spare time.  The machine really is abysmal to use without the angle mod and something to make adjusting the compound easier.
> 
> So net net it was a lot of work but I also learned and know feel pretty confident with how the machine works and I have a better sense for what features I would appreciate on a lathe in the future.  I do not think I would make this purchase again.  As with most things you get what you pay for.


hi I have the same wm210v machine and I have the same problem gear charts are all wrong have you found the right chart for this tour


greenail said:


> I bought a bit of an oddball lathe and wanted to share my thoughts in case someone else is considering the machine.  This is essentially the same as the WM210 WM180, MX210, and G0678 other than the MT5 difference.
> 
> This is very close to the standard 200x400 or 8x16 but instead of the MT3 chuck it has an MT5.  The main implication for this change is that the drive gear on the spindle is 56 tooth vs 40 tooth and the pulley setup will also be more snug though it is unclear what belts are needed.  I just broke a belt and I don't really trust the manual the machine came with since the threading gear charts are all wrong.  The manual says 5M360 but that seems to be a very uncommon belt type.  The grizzly manual for this machine says it needs 5M365 and 5M375 belts.  I asked the seller on ebay and they sent me a picture of a 5M375 belt.
> 
> When I received the machine it was clearly rolling around the whole trip with a single bolt securing it.  It took a big dent in the front cover, bent the gear cover bolt, as well as a few other issues.  I should have refused shipment.  The seller has been very responsive and claims to be sending replacement parts for everything.
> 
> I was able to get the machine started and running but it was filthy with grinding dust and needed to be fully stripped down and cleaned.   It did not have cosmoline on it, rather a snotty gelatin type goop which was much easier to clean than the cosmoline.
> 
> The first problem I discovered was that the hold downs for the ways did not have any counter adjusting grub screws and looked like they were machined with a dull carp.  I ended up squaring and milling them on my mill and tapping 3 m5 grub screws so I could adjust the fit to the ways.  Without this adjustment there was at least .125" of slop rocking the cross slide.
> 
> The next problem was the carrage lock.  It was drilled and tapped cocked around 10 degrees off.  I've abandoned the factory setup and need to do a custom carriage lock later.
> 
> Many of the castings on the cross slide and compound were extreemly rough.  They required heavy deburring, some needed time on the milling machine, and they needed lapping.  I ended up installing a OXA quick change tool post and did the compound through hole mod to allow me to adjust the angle of the compound without unscrewing it 90% of the way.
> 
> The tailstock was about .25" off and locked up so it had to be fully stripped down.  It turned out there was not enough room for adjustment and it required some filing and milling to square up.  I also needed to shim it to get the height correct.  Finally the locking mechanism required adjustment to get working properly.
> 
> I believe the reason I broke the belt was that it was over tight.  I was unable to change the belt without going into the back of the lathe to unfasten the bolt on the inside of the electronics cover.  There are some blogs on ways to fix this so you can change the speed without this extra work.  This seems like a pretty intensive mod and I didn't really need the speed yet so I had put it off.  Then my belt broke.
> 
> The final mod I did was to put a bearing on the compound slide.  The compound is impossible to turn without binding.   It is very hard to adjust it without lapping due to the extremely poor milling.  Combining this with the very loos bushing fit and you will find it binds on any attempt to turn the compound with one hand.  My bearing fix is pretty much a hack and I'm going to redo it when I have some spare time.  The machine really is abysmal to use without the angle mod and something to make adjusting the compound easier.
> 
> So net net it was a lot of work but I also learned and know feel pretty confident with how the machine works and I have a better sense for what features I would appreciate on a lathe in the future.  I do not think I would make this purchase again.  As with most things you get what you pay for.




hi I have the same wm210v machine and I have the same problem gear charts are all wrong have you found the right chart for this LATHE


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## bogguey

bogguey said:


> have you found the right chart for this lathe


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## hman

greenail said:


> i've been trying to do some threading and I don't know why but I can't seem to get anything to work out but the first thread i tried for a 12mm standard od.
> the manual is clearly not accurate as the headstock has a gear with 56 teeth on it.  The gear cover has a chart on it but i can't fit the combination for 0.5mm pitch on the banjo.  really disappointed in this lathe.
> I also discovered the headstock was out about .1m over 50mm.  there are only 2 M8 screws holding the headstock down and it was  misaligned by quite a lot based on the bolt hole locations.
> the last thing i tried was a straight combination of 56 80 30 60 which should produce .35 turns on the leadscrew but the output was closer to 1.75  based on my threading gauge.  I can't find a calculator that works for this headstock gear size...


Let me try to help.  You haven't posted any pictures of your lathe, and I know nothing else about it.  Apologies if this is already known to you.  But I'm going to get pretty basic and somewhat generic, just for the sake of completeness.
1.  I assume you have gears both in the headstock and in a QCGB (quick change gear box) just ahead of the leadscrew.  The thread pitch will be a combination of both gear sets, plus the lead of the leadscrew. 
2.  Headstock gears - If a series of gears is meshing with each other (ie, in a common plane), then intermediate gears don't affect the final ratio. The ratio is determined by the tooth counts of the first and last gears only.  If a pair of gears is on a common shaft  (ie, cluster), with previous gears driving one of them and subsequent gears being driven by the other, this tooth ratio must be multiplied in.
3. Commonly used sets of cluster gears for metric threads are shown in the table below.  Only the 127/120 gives "exact" metric threads on an inch lathe, or "exact" inch threads on a metric lathe.   The last column gives the thread pitch error of the alternate sets.  You mentioned having a 56 tooth gear.  It should be "clustered" with a 44 tooth.  Assuming you have an inch lathe - your leadscrew has threads evenly divisible by inches, you'll want the headstock gear (and intermediate gear if used) to drive the 56 tooth gear.  Subsequent gears should be driven by the 44 tooth gear.







4.  If you have a QCGB, you'll want to open it up and do tooth counts of all the gears.  This will give you a set of possible ratios.  Note that the last gear in the headstock is on a shaft common with the gear(s) in the QCGB, so this constitutes a cluster.  If no QCGB, you're driving the leadscrew directly from the last headstock gear, so no additional ratio needs to be factored in.
5.  Once you've calculated the turns ratio between the spindle and the leadscrew, you multiply by the pitch (inches per turn) of the leadscrew to get the inches of carriage movement per spindle turn ... the thread pitch you will cut.

Here are two gear calculators that might be of help:








						Change Gears for Threading
					

This calculator determines the correct change gears for any thread pitch. Works for all mini lathes and HiTorque Bench Lathes.




					littlemachineshop.com
				





			Site Unavailable | WestHost
		


And here's the diagram I made for metric threading on my 12x24 lathe.  Note the pictorial in the upper left, showing how the gears are arranged.  The "A" gear is on a shaft driven by the spindle through some internal gearing, so it's part of a cluster, and thus becomes part of the final ratio.  The "SET" column indicates the settings of the two levers of my QCGB.






If you could, please go ahead and post some photos of your headstock gearing setup, etc.  Given specific info, I (we) can offer more specific advice.


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## bogguey

hman said:


> Let me try to help.  You haven't posted any pictures of your lathe, and I know nothing else about it.  Apologies if this is already known to you.  But I'm going to get pretty basic and somewhat generic, just for the sake of completeness.
> 1.  I assume you have gears both in the headstock and in a QCGB (quick change gear box) just ahead of the leadscrew.  The thread pitch will be a combination of both gear sets, plus the lead of the leadscrew.
> 2.  Headstock gears - If a series of gears is meshing with each other (ie, in a common plane), then intermediate gears don't affect the final ratio. The ratio is determined by the tooth counts of the first and last gears only.  If a pair of gears is on a common shaft  (ie, cluster), with previous gears driving one of them and subsequent gears being driven by the other, this tooth ratio must be multiplied in.
> 3. Commonly used sets of cluster gears for metric threads are shown in the table below.  Only the 127/120 gives "exact" metric threads on an inch lathe, or "exact" inch threads on a metric lathe.   The last column gives the thread pitch error of the alternate sets.  You mentioned having a 56 tooth gear.  It should be "clustered" with a 44 tooth.  Assuming you have an inch lathe - your leadscrew has threads evenly divisible by inches, you'll want the headstock gear (and intermediate gear if used) to drive the 56 tooth gear.  Subsequent gears should be driven by the 44 tooth gear.
> 
> View attachment 341687
> 
> 
> 4.  If you have a QCGB, you'll want to open it up and do tooth counts of all the gears.  This will give you a set of possible ratios.  Note that the last gear in the headstock is on a shaft common with the gear(s) in the QCGB, so this constitutes a cluster.  If no QCGB, you're driving the leadscrew directly from the last headstock gear, so no additional ratio needs to be factored in.
> 5.  Once you've calculated the turns ratio between the spindle and the leadscrew, you multiply by the pitch (inches per turn) of the leadscrew to get the inches of carriage movement per spindle turn ... the thread pitch you will cut.
> 
> Here are two gear calculators that might be of help:
> 
> 
> 
> 
> 
> 
> 
> 
> Change Gears for Threading
> 
> 
> This calculator determines the correct change gears for any thread pitch. Works for all mini lathes and HiTorque Bench Lathes.
> 
> 
> 
> 
> littlemachineshop.com
> 
> 
> 
> 
> 
> 
> Site Unavailable | WestHost
> 
> 
> 
> And here's the diagram I made for metric threading on my 12x24 lathe.  Note the pictorial in the upper left, showing how the gears are arranged.  The "A" gear is on a shaft driven by the spindle through some internal gearing, so it's part of a cluster, and thus becomes part of the final ratio.  The "SET" column indicates the settings of the two levers of my QCGB.
> 
> View attachment 341688
> 
> 
> If you could, please go ahead and post some photos of your headstock gearing setup, etc.  Given specific info, I (we) can offer more specific advice.


I don't really understand your explanation, it is very complicated. here is a picture of the chart of my chinese lathe, i tried 10 different thread combinations and none i got the right result


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## hman

That's a strange looking chart!  I can only guess what the "H" means - probably something like "immaterial," because whatever  other gear there is mounted on the common shaft is not used.  I'll also assume that the vertical dashes on the chart indicate meshed gears.  

Let's check something first ... is the gear on the spindle 56 teeth?  If so, you can probably use the following setup.  If not, I don't know what to tell you.

As best I can interpret the chart, for 0.5mm thread, you mount a 50 tooth gear and "anything else" on the upper post.  Per the vertical hash mark on the chart, mesh the 50 tooth "A" gear with the 56 tooth spindle gear above.  Place 80 tooth and 30 tooth gears on the second shaft.  Mesh the 80 tooth "C" with the 50 tooth "A" gear above.  The bottom shaft (which I guess drives the leadscrew directly) should have an 84 tooth and "anything else" on it.  Mesh the 84 tooth "F" gear with the 30 tooth "D" gear above.

This combination should give you a ratio of 56/80 X 30/84, or 0.250 leadscrew turns per spindle turn.  If your leadscrew has a (metric) pitch of 2mm per turn, you should get a metric thread of 0.5mm.  (56 teeth per spindle turn) X (30 teeth/80 teeth) X (1 leadscrewturn/84 teeth) X (2mm/leadscrew turn) = 0.5mm per spindle turn.

That's the best I can offer.  If this does indeed get you 0.5mm threads, you now hve a "template" to follow for other threads.  Again, if I've misunderstood the symbols on the threading chart, I don't know what else to say.  Good luck!


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## greenail

I added an electronic leadscrew (half implemented) and you can see some of the surface finish it was able to produce in some mystery metal and aluminum.  I re-machined a 6" backplate and saw a really good surface finish for the first time around 2" from the center.  The backplate was bolted directly to the spindle flange so it was as rigid as you can get with this lathe.  It was quite a joy to see the nice blue chips and  such an amazing surface finish.  I don't think i'm brave enough to run the thing at a high enough RPM for the smaller diameters and carbide to make a really good finish.  The spindle wall is just so thin I wonder what would happen if it was running 2k rpm and it failed!

An additional complaint.  While the thing is actually running pretty well with the tweaks to the bearing preload, removal of the cross slide, and lots of attention to shimming the saddle, it has  very severe increase in thickness of the bottom surface under the front way.  This makes it crazy tight and almost unmovable when the tool is moved up close to the spindle flange.  This may have added the rigidity needed to product the great surface finish I got on the backplate but it is too tight to be practical.  With the chuck on this isn't so bad and I haven't bothered to try to scrape it in.

I bought new timkin bearings for it but I have not put them on yet.  I'll let folks know if that is an improvemnt when I get around to installing them.


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## Hard_ware

The lathe will cut metric threads no problem with correct gears.
Imperial threads as well except you cannot disengage the lead-screw you need to backout and run in reverse back to starting point to start your next pass.
When cutting 1mm threads (25.4TPI) you can engage and disengage the lead screw whenever you want.

A C E are the left side gears, BDF are the right side gears.

The spindle gear 56 tooth is not shown in the chart but is needed in the calculation.  So to calculate you start on the left side top 56spindle not shown divided by last gear on that side(any gear in the middle is just an idler only fills the gap).  Times the first gear on the right side  divided by the last gear on the right side. This is the ratio of chuck revolution to lead screw revolution.
Lead screw is 2mm so you multiply the ratio with the 2mm lead screw and the amount of travel you get *per chuck revolution*.  If you travel 1mm per chuck revolution well you are cutting 1mm threads. If you travel 1.5mm per REV you are cutting 1.5mm threads.  IF you travel .9071mm per REV  you are cutting 28.00 TPI .  Pretty simple.
Now for the calculations for the gears needed to cut threads not very simple,  a gear calculator is really needed. But with the basic math above you can check if the gears will work.  To cut imperial with a metric lead screw you are best served with a 127tooth gear but other gear sets can get you very close. Best program I have found is change gears.js  you add your lathe dimensions and gears you have and it will calculate the setup.

Add a lathe  MV-210   wheel on headstock *56* tooth, Pitch of lead-screw *2.000* mm, smallest size fo 1st wheel *50,*  Min difference* 10*, modul *1.0*,   *150mm* , *140mm*.  *Now enter your gears* you have and click *ok*.

Now you can calculate what gear combo's will cut what threads.  3D printed gears work fine I have not broken a single tooth yet.
A 127 tooth gear will add accuracy to gears needed to cut Imperial threads as well as very fine cutting .002 cut per rev (approx 461 TPI) .  Printing combo gears makes changing gears faster as you only need to slide them on the shaft no keyed insert needed as the gears are printed together.

Here is an example  going from metric 1mm pitch to 24TPI  only need to change middle set and adjust middle and top gear shafts for proper distance. Use a folded piece of paper to space gears so they turn freely. Slide folded paper strip in between gears and press gears together while you tighten the shaft they are mounted on.  This will give them a little space to turn freely, makes a big difference.

1mm
top post 84  xx  mid post   28 20  spindle shaft xx 80. .....56/28 (84 idler doesn't matter  only 1st and last gear in the same row matter) x 20/80=.5 ratio chuck to lead screw  x lead screw pitch 2mm = 1mm travel per chuck rev. .....84 gear is a fill the gap gear (idler) does not count you can substitute it with a smaller gear if needed. xx is a spacer.


24TPI
top 84 xx     mid 41 31 spindle shaft xx 80 .  .....56/41 x 31/80 =.52926829 ratio  x  2mm lead screw = 1.05853659 lead screw travel per 1 chuck rev in mm   ......now to convert this to inches    25.4 / 1.05853659 travel per rev  in mm = 23.995 TPI 
Hope you can follow.
Graphic display of gears in the change gear program will be mirror image  so left gears go on right side and vice versa.
You can see this as only one side attaches to the spindle gear.


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## kingjamez

I just bought one of these that didn’t come with a chuck at all.

Anyone have an extra that they have replaced with a better one?

Any suggestions on a quality aftermarket chuck that has a sufficient through bore but doesn’t break the bank?
-Jim


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## Hard_ware

kingjamez said:


> I just bought one of these that didn’t come with a chuck at all.
> 
> Anyone have an extra that they have replaced with a better one?
> 
> Any suggestions on a quality aftermarket chuck that has a sufficient through bore but doesn’t break the bank?
> -Jim


The k12-160 is cheap 4 jaw but you will have to make an adapter plate or cut the register on the lathe spindle  to 65mm and drill and tap 4 bolt holes. Front mounted bolts thru chuck so not a big deal.  6” 4 jaw with 1.625 pass thru.  About $86 eBay shipped.


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## jdm23

hman said:


> That's a strange looking chart!  I can only guess what the "H" means - probably something like "immaterial," because whatever  other gear there is mounted on the common shaft is not used.


It's really nothing of importance but having read on various forums people wondering about what H means, here's my take, it doesn't stand for a word in any language, it just graphically reminds of the spacer - two vertical faces with a through hole.

Also wanted to share this gear calculator which covered perfectly a 40T spindle while no other did
http://kachurovskiy.com/gears/


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## hman

jdm23 said:


> It's really nothing but having read on various forums people wondering about what H means, here's my take, it doesn't stand for a word in any language, it just graphically reminds of a the spacer - two vertical faces with a through hole.


Durn!  I think you've nailed it.  Never even thught of that possibility.  Many thanks!


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## Hard_ware

jdm23 said:


> It's really nothing of importance but having read on various forums people wondering about what H means, here's my take, it doesn't stand for a word in any language, it just graphically reminds of the spacer - two vertical faces with a through hole.
> 
> Also wanted to share this gear calculator which covered perfectly a 40T spindle while no other did
> http://kachurovskiy.com/gears/


Adding a 127 gear makes cutting Imperial possible with .001 accuracy.
You can change the spindle gear to whatever your lathe uses.
38mm big bore versions use 56 tooth spindle.


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## jdm23

Hard_ware said:


> You can change the spindle gear to whatever your lathe uses.



I did a comparison of the two applications mentioned, but ran into a problem with ChangeWheels.
I entered my lathe data to the best I could understand some parameters






For 1mm pitch It gives the following:






Evidently, of all the possible alternatives, the program *only gives the one with the biggest available gear as first,* but that won't work well with my lathe, as the quadrant cover wouldn't fit, one would have to work without it and the safety switch pushed. *I really recommend against that.*
Of course If I remove from config all gears above 60T I get an usable setup, but that is not a good solution as will not work with all pitches.
So, to be really applicable to any lathe the program would need to list all the alternatives, and/or support additional gear size parameters.

On the other hand, Kachurovskiy's online calculator is simpler, does not consider any physical constraint, and shows all the possible alternatives for a given pitch and the nearest approximate ones





as well all the possibly supported pitches, and a simple graphical representation. I like it for two more reasons, first being browser based it can be used on a mobile device when one is to the lathe, and then since it's open source it has room for any kind of improvement.

Anyway, the original reason I went looking into calculators is that I will need to cut a non-standard pitch for an antique clock restoration.






Calipers was at 6mm in the pic above, and my assumption is that is a 1/4 of French Ligne, or 0.56mm.
I haven't defined yet the pitch diameter or profile. Both applications give a consistent solution for this pitch, and with that I hope to be able to cut my very 1st thread successfully.


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## Hard_ware

jdm23 said:


> I did a comparison of the two applications mentioned, but ran into a problem with ChangeWheels.
> I entered my lathe data to the best I could understand some parameters
> 
> View attachment 353113
> 
> 
> For 1mm pitch It gives the following:
> 
> View attachment 353114
> 
> 
> Evidently, of all the possible alternatives, the program *only gives the one with the biggest available gear as first,* but that won't work well with my lathe, as the quadrant cover wouldn't fit, one would have to work without it and the safety switch pushed. *I really recommend against that.*
> Of course If I remove from config all gears above 60T I get an usable setup, but that is not a good solution as will not work with all pitches.
> So, to be really applicable to any lathe the program would need to list all the alternatives, and/or support additional gear size parameters.
> 
> On the other hand, Kachurovskiy's online calculator is simpler, does not consider any physical constraint, and shows all the possible alternatives for a given pitch and the nearest approximate ones
> View attachment 353120
> 
> 
> as well all the possibly supported pitches, and a simple graphical representation. I like it for two more reasons, first being browser based it can be used on a mobile device when one is to the lathe, and then since it's open source it has room for any kind of improvement.
> 
> Anyway, the original reason I went looking into calculators is that I will need to cut a non-standard pitch for an antique clock restoration.
> 
> View attachment 353121
> 
> 
> Calipers was at 6mm in the pic above, and my assumption is that is a 1/4 of French Ligne, or 0.56mm.
> I haven't defined yet the pitch diameter or profile. Both applications give a consistent solution for this pitch, and with that I hope to be able to cut my very 1st thread successfully.


I think you can change the module to 1.0 or try different ones from 1.0-1.8 .
 The other program works great as long as you follow the gear pattern properly.

Post finished thread when you cut it.


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## jdm23

Hard_ware said:


> I think you can change the module to 1.0 or try different ones from 1.0-1.8


My lathe has module 1.5 gears, that is confirmed of a gear with a given number having exactly the expected diameter. 




Hard_ware said:


> But the other program works great as long as you follow the hear pattern properly.



It works but as I have explained when the only proposed combination makes impossible to replace the cover that is an unacceptable risk to me.


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## Hard_ware

jdm23 said:


> My lathe has module 1.5 gears, that is confirmed of a gear with a given number having exactly the expected diameter.
> 
> 
> 
> 
> It works but as I have explained when the only proposed combination makes impossible to replace the cover that is an unacceptable risk to me.



 On any gear chart a gear in the middle of a single row( not the first or last) the number of teeth does not matter it's just used as a spacer or idler gear.
So the large gear meshing with the spindle gear you are talking about is just used as an idler, you can put any gear you want that fits in its place so your cover will close for safety.

I do like the other program because it lists a 5 gear chain (3 pairs) which expands the ratios available greatly.


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## greenail

I can't be 100% sure but shortening the distance to the spindle flange seems to be the best mod i've made for this lathe.  In the video I parted some steel and it was better but not great.  I just sharpened up my parting tool a bit and it is parting steel like a dream!!!!


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## kingjamez

Very interesting result. Great work and thanks for sharing.

It's clear to me from mine, and the above video that another seeming *requirement* is to upgrade the motor to something with a lot more torque. It won't be cheap, but will vastly improve the entire machine.


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## greenail

kingjamez said:


> Very interesting result. Great work and thanks for sharing.
> 
> It's clear to me from mine, and the above video that another seeming *requirement* is to upgrade the motor to something with a lot more torque. It won't be cheap, but will vastly improve the entire machine.



lack of torque at low rpm is a definite problem.  I may slap a sewing servo motor on it to see how it runs.


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## jdm23

greenail said:


> lack of torque at low rpm is a definite problem.  I may slap a sewing servo motor on it to see how it runs.


I was investigating DC brushless motors, triphase, VFC inverters and the shebang then realized that the space above the motor can take a countershaft there, in fact there are models which have that. I would be OK with another 2:1 reduction, for sure I don't need 3000 rpm and not even 1500 on my 250mm lathe.


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## ScottGunSmith

Hard_ware said:


> The lathe will cut metric threads no problem with correct gears.
> Imperial threads as well except you cannot disengage the lead-screw you need to backout and run in reverse back to starting point to start your next pass.
> When cutting 1mm threads (25.4TPI) you can engage and disengage the lead screw whenever you want.
> 
> A C E are the left side gears, BDF are the right side gears.
> 
> The spindle gear 56 tooth is not shown in the chart but is needed in the calculation.  So to calculate you start on the left side top 56spindle not shown divided by last gear on that side(any gear in the middle is just an idler only fills the gap).  Times the first gear on the right side  divided by the last gear on the right side. This is the ratio of chuck revolution to lead screw revolution.
> Lead screw is 2mm so you multiply the ratio with the 2mm lead screw and the amount of travel you get *per chuck revolution*.  If you travel 1mm per chuck revolution well you are cutting 1mm threads. If you travel 1.5mm per REV you are cutting 1.5mm threads.  IF you travel .9071mm per REV  you are cutting 28.00 TPI .  Pretty simple.
> Now for the calculations for the gears needed to cut threads not very simple,  a gear calculator is really needed. But with the basic math above you can check if the gears will work.  To cut imperial with a metric lead screw you are best served with a 127tooth gear but other gear sets can get you very close. Best program I have found is change gears.js  you add your lathe dimensions and gears you have and it will calculate the setup.
> 
> Add a lathe  MV-210   wheel on headstock *56* tooth, Pitch of lead-screw *2.000* mm, smallest size fo 1st wheel *50,*  Min difference* 10*, modul *1.0*,   *150mm* , *140mm*.  *Now enter your gears* you have and click *ok*.
> 
> Now you can calculate what gear combo's will cut what threads.  3D printed gears work fine I have not broken a single tooth yet.
> A 127 tooth gear will add accuracy to gears needed to cut Imperial threads as well as very fine cutting .002 cut per rev (approx 461 TPI) .  Printing combo gears makes changing gears faster as you only need to slide them on the shaft no keyed insert needed as the gears are printed together.
> 
> Here is an example  going from metric 1mm pitch to 24TPI  only need to change middle set and adjust middle and top gear shafts for proper distance. Use a folded piece of paper to space gears so they turn freely. Slide folded paper strip in between gears and press gears together while you tighten the shaft they are mounted on.  This will give them a little space to turn freely, makes a big difference.
> 
> 1mm
> 84  xx    .....56/28 x 20/80=.5 ratio chuck to lead screw  x lead screw pitch 2mm = 1mm travel per chuck rev    good
> 28  20   ......84 gear is a fill the gap gear does not count
> xx  80
> 
> 24TPI
> 84 xx       ......56/41 x 31/80 =.52926829 ratio  x  2mm lead screw = 1.05853659 travel per rev in mm
> 41  31      ......now to convert this to inches    25.4 / 1.05853659 travel per rev  in mm = 23.995 TPI good
> xx  80
> 
> Hope you can follow.
> Graphic display of gears in the change gear program will be mirror image  so left gears go on right side and vice versa.
> You can see this as only one side attaches to the spindle gear.


@Hard_ware I sincerely appreciate this. I have been scouring the internet for a few days now. Still not sure if I have it figured out but this app and your input has really helped. I owe you a beer.


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## jdm23

jdm23 said:


> I was investigating DC brushless motors, triphase, VFC inverters and the shebang then realized that the space above the motor can take a countershaft there, in fact there are models which have that. I would be OK with another 2:1 reduction, for sure I don't need 3000 rpm and not even 1500 on my 250mm lathe.



There, speed reducer done:








						More torque from 250mm lathe, my way.
					

I find the lack of torque at low speed to be too much of a problem, it prevents or makes very difficult to do some work that would be straightforward on a 'real' lathe, even a small one. So I went to do something about it. This is a quick summary of how I did it, there is no BOM, drawings or...




					www.hobby-machinist.com
				







ScottGunSmith said:


> @Hard_ware I sincerely appreciate this. I have been scouring the internet for a few days now. Still not sure if I have it figured out but this app and your input has really helped. I owe you a beer.


I have also developed an online/offline calculator, with native metric and imperial support








						New Lathe Change Wheels Calculator
					

Time ago I needed to cut a non standard thread on my Chinese 250mm lathe, finding the solution was not difficult, but I remained a bit unsatisfied with the available calculators, both online or Windows executables, so I started working on an existing one and made a bunch of improvements to it...




					www.hobby-machinist.com


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## Hard_ware

ScottGunSmith said:


> @Hard_ware I sincerely appreciate this. I have been scouring the internet for a few days now. Still not sure if I have it figured out but this app and your input has really helped. I owe you a beer.




Here are some gear combos.
The I is for idler gears you can substitute whatever fits best if needed.
The 56 is the spindle gear.

20TPI =20.01212
40-30
66-84
52-xx


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