# Is it possible to make precision ball screws with a manual lathe?



## rajhliux (Jul 17, 2020)

I'm in the market to purchase a quality precision lathe which will be used for threading custom water pipe fittings.

Wondering if it is also possible to make precision ball screws from the lathe which will be then used for a custom build of a CNC mill.

Any thoughts?

Thanks!


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## JimDawson (Jul 17, 2020)

Possible?  Yes, but maybe not practical.


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## JRaut (Jul 17, 2020)

Nope.

The most precise ball screws are ground to extremely, extremely tight tolerances out of very hard materials.

Even run-of-the-mill ball screws are rolled to tolerances much tighter than the leadscrew on most/all manual lathes, particularly those in the $3000 (which I gather from your other posts is the range you're looking at).

If you want a precision ball screw, you've got to pay the piper.


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## Mini Cooper S (Jul 17, 2020)

Short answer is no. Common manual lathes are just not built to the extreme tolerances needed to make a ball screw.

Richard


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## rajhliux (Jul 17, 2020)

JRaut said:


> Nope.
> 
> The most precise ball screws are ground to extremely, extremely tight tolerances out of very hard materials.
> 
> ...



So how precision ball screws are made, properly? Using a super expensive manual lathe or some other type of machinery?

Thanks!


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## JimDawson (Jul 17, 2020)

A super expensive ball screw grinding machine or a super expensive thread rolling machine.


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## Charles Spencer (Aug 22, 2020)

"The ball screw was invented independently by H.M. Stevenson and D. Glenn who were issued in 1898 patents 601,451 and 610,044 respectively.

Early precise screwshafts were produced by starting with a low precision screwshaft, and then lapping the shaft with several spring-loaded nut laps.  By rearranging and inverting the nut laps, the lengthwise errors of the nuts and shaft were averaged.  Then, the very repeatable shaft's pitch is measured against a distance standard.  A similar process is sometimes used today to produce reference standard screw shafts, or master manufacturing screw shafts."








						Ball screw - Wikipedia
					






					en.wikipedia.org


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## jmkasunich (Aug 22, 2020)

Everybody seems to be focused on the precision but even more important is that ballscrews need to be VERY hard.  Ground screws are hardened first then ground, not cut on a lathe.  Rolled screws are rolled to shape on a dedicated machine (very heavy duty, far heavier than almost any lathe), then case hardened and polished.  Neither one can be made on a regular or CNC lathe.  A good explanation of the processes involved at the link below
https://blog.misumiusa.com/rolled-vs-ground-ball-screws-advantages-disadvantages/


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## dirty tools (Aug 22, 2020)

YES
it will take lots of time and very precise work 
you can make them by hand if you’re have time


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## Richard King 2 (Aug 23, 2020)

I just Googled "cheap ball screws" and there is several places who sell them.  Probably made in China.  By the time you tried to make one, buy material, tooling and fail you could have bought a cheap one.


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## Eddyde (Aug 23, 2020)

Note: the OP was a troll and has been banned.


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