I know these are relatively(?) inexpensive c7- c10 accuracy ballscrews. Is there any way of improving backlash issue, mounting double nuts or whatever? Do I really have to spend $1000 per screw to get close to c5 level (0.0005)?

Thanks

You can use either double nuts, or add larger balls to remove backlash. Mach3 has screw mapping to compensate for errors, but to set it up within .0005, You'd probably be better off spending the $1000 per screw. :)

Thanks Gerry. My machine will likely go beyond hobby one day and I probably should not cut corners. What about the double nut idea. How do you do that? Is it reliable and long lasting or not really? :)

Walter have you tried THK they have an online store . I have an account with them tell me the size you need and i will tell you what they cost . https://www.tos-world.com/webapp/wcs/stores/servlet/StoreCatalogDisplay?catalogId=10051&storeId=10001&langId=-1&topcategoryId=11551&msgFlg=Y

Double nuts will address backlash, they do not address accuracy.

http://www.industrialhobbies.com

Look in the tips for homemade ballnuts.

Thank you all. Links are very helpfull.

Timlkallam, online store shows rolled type. They still may have better accuracy and less backlash. Can you find out the price for BTK1405 or BTK1808 ?

(BTK1405-2.6ZZ nut + TS1405-1500L shaft)
(BTK1808-3.6ZZ nut + TS1808-1500L shaft)

I appreciate your help.

Hello Walter here are the THK prices, I can't tell what grade these shafts are ,if backlash is a problem you could use 2 ballnuts per shaft.I have never bought ballscrews from thk only linear rails.
(BTK1405-2.6ZZ nut + TS1405-1500L shaft) ball nut is $122 14mm shaft is $112
(BTK1808-3.6ZZ nut + TS1808-1500L shaft) ball nut is $157 18 mm shaft is $146

Thank you Timlkallam. That helps.

They don`t list precision ground ballscrews online, only rolled c7-c10 class. But prices are ok, less than I thought ;) And THK is well known for quality stuff...


Thanks again