# Modifying a small Chinese lathe



## Energie (Jul 30, 2011)

Some time ago I bought a small Chinese lathe and made some modifications.


*Quantum D210x400*







*Stock electric :shakehead*






*New AC converter Siemens Sinamics (speed control)*






*Stock Chinese chuck 100 mm, new Bison steel chuck 125 mm*






*Checking the spindle temperature*
cleaned, relubed and adjusted the bearings



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*Cross-slide, too much play*






Shorter screw-head


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## Energie (Jul 30, 2011)

*Threaded bolt was too short for a Multifix A toolpost*













*New version*













*Upper slide without bearings*


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## Energie (Jul 30, 2011)

*Some more pics:*

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## gadget_lover (Jul 30, 2011)

That's a lot of nice work there. It's tough to find enough room for adding things to the smaller lathes, and looks like you did a great job of it.

Thanks for sharing.

Daniel


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## Al Combs (Jul 30, 2011)

+1 To that being a very nice job of modding. I particularly like the adaptation of the calipers as DRO's. I'm sure that will give many of the 7x14 guys some much needed inspiration. Thanks for taking the time to share.


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## Anglepoise (Jul 30, 2011)

Very nice job. Don't see many Multifix tool posts over this side of the pond. Thrust washers on the crosslide make a huge improvement


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## wquiles (Jul 30, 2011)

Outstanding upgrades - nicely done!


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## darkzero (Jul 30, 2011)

I've always been a fan of your work! Now I can really see why! 

I also like how you refinished the saddle with the bare finish! Looks much better than painted.


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## ICUDoc (Jul 31, 2011)

Great thread and photos: thanks a lot.
I am inspired to look at bearings for my lathes slides...
Thanks a lot!
EDIT: on looking at the photos I am struck by how deliciously clean your machining is: Beautiful!
Once you got all the bearings sorted, did the machine cut more accurately and well??
And do you find it needs more mass/weight/ballast to prevent vibration?
I guess what I want to know is: does the outlay of time, effort and money you have put into the machine make it MUCH better? Still cheaper than buying a Wabeco or similar?
And thanks again!


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## precisionworks (Jul 31, 2011)

Very nice machine work  

Those modifications are always worthwhile as long as you plan to keep the machine for sometime. When that machine is traded for a larger one, the same mods plus a few more will be needed. It is safe to figure 40 hours of effort on every Chinese machine tool you buy. 

My 1986 south bend 10k had about 10 hours of use what I bought it. During the 9 or 10 years that it made parts, I remember adjusting the headstock bearings, replacing 1 belt, &reaming the tail stock taper. Probably 5 hours time spent during all those years. 

The Wabeco Machines should be similar in their design construction fit and finish. They should be almost perfect right out of the box. The decision to buy that machine versus a chinese machine depends both on your budget and the value of your time. Calculate what you earn at work X 40 and you will have the cost of correcting a Chinese machine. 

My 14x40 heavy ate up $4000 of billable time to make it into a usable machine that was accurate and pleasant to work with. Since I did not have $4000 in my bank account, the machine was modified whenever I could catch a few hours between jobs. For $20,000 a similar size machine to be purchased that would be plug and play.

You'll spend a good amount of money either where you go.



> Still cheaper than buying a Wabeco or similar?


If you have the money in the bank for a Wabeco, Haas, or one of the Eastern European machines, they may well cost less than an "inexpensive" Chinese machine - after your labor is figured in. 

My dream machine is a medium size Haas tool room lathe, the TL3-W. With a 3.5" spindle bore and 18" swing over the cross slide, the capacity is just right for the size jobs I do. Not too heavy at 3000 kg, and the 30hp spindle would make quick work of any material. Only 56,995 reasons why there isn't one in my shop  It's similar to the Wabeco in build quality & would need nothing other than power to make chips. In the end, it all boils down to what you want, what you need, what you can afford, and how much time can be invested to make it right.


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## Energie (Jul 31, 2011)

*@All:* thanks for the kind words!

*@darkzero:* sharp eyes 





ICUDoc said:


> Once you got all the bearings sorted, did the machine cut more accurately and well??


 
Yes, there is a noticeable difference. The surfaces (especially stainless steel) are much better now.




ICUDoc said:


> And do you find it needs more mass/weight/ballast to prevent vibration?


 
No, the mass (110 kg (...of the machine)) is ok.
I use a small watchmakers lathe (8 kg), which delivers excellent results.







But the vibration was indeed a problem (at higher speeds).
The reason was the backplate of the new 125 mm chuck.




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I had to balcance the green hole.




ICUDoc said:


> I guess what I want to know is: does the outlay of time, effort and money you have put into the machine make it MUCH better? Still cheaper than buying a Wabeco or similar?


 
Yes it is much better now. Not cheaper than a Wabeco but exact what I need.

The Wabecos are very nice machines, but the disadvantage is their DC-drive and the (belt) gears, which are not easy to change.




precisionworks said:


> ...You'll spend a good amount of money either where you go...


 





Kind regards

Herbert


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## ICUDoc (Aug 1, 2011)

Barry / Herbert
Thanks very much for your comments.
After a difficult year I have tidied up the workroom and I'm contemplating whether to spend time on the lathe to bring it up to scratch (a pleasurable task in itself) or to buy a really high-quality unit and just make stuff. 
This thread has been a pleasure!
Barry- the (work income x 40 hours) is an interesting equation!! Makes me quite unsure which way to go....


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## precisionworks (Aug 1, 2011)

> the (work income x 40 hours) is an interesting equation!! Makes me quite unsure which way to go....


The best machinist I've ever known (who was also my boss & mentor for a year at the mine repair shop) always said "Buy the best machine you can afford & then some "

There is a lot to be said for plug-n-play, and the Wabeco machines are just that. But you'll learn the inner workings of a lathe if you buy and rebuild a Chinese machine. Depends on what you want to do.

One of the sites I post on encourages all new lathe owners to learn to grind HSS tools. I did learn that in the late 1960's, but never much used the skill as inserts were already common at that time. IMO, learning to grind HSS tools takes hours & days of effort that could better be put into learning about feeds, speeds, depths of cut, etc. Threading too. (I still grind a HSS tool on rare occasion, usually a form tool, so it's something worth learning when needed.)

One thing I so dislike about Chinese machine tools, mine included, is that most are buttugly. Because my lathe is larger than average, it is also more ugly than average. Not a rounded or sculpted corner or feature anywhere. I sorely missed my beautiful South Bend for weeks, as it had a classic 1950's look. 






The "new" machine quickly grew on me, especially when peeling off .200" depth of cut, something the SB could never do. It seems that a person gets accustomed to almost anything after a while. European machines are better built & better looking that most anything available today ... with the exception of Japanese machine tools, which are generally awesome.


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