Hello,

in my quest to get going on my lathe conversion i've been having a bit of a look at various ballnut sellers and have been left with some questions.

i'm looking to get as low a lash as is possible without going to bonkers on price :)

How many nuts should be used?

i see that some people use 2 non preloaded nuts with springs to preload between them,

then theirs the preloaded nuts(ones that are labled that way are much pricier)

and the double ball buts(2 seperate nuts packaged together and preloaded).

i have noticed that all the china sourced ball screws and nuts are a bit vague on their backlash specs, what sort of backlash should one expect due just to using a c7 roled ballnut of chineas origin?

Are the pre loaded nuts actualy naturaly backlash free in use?

The double nuts in a single package, beter value than 2 singles and making some sort of preload mount?

Ball returns, plastic tubes, external metal tubes or end circulation? Whats the deal, any difference or just cosmetic/down to space requirements?

Hope i'm not asking too many basic questions but i had a look at zap automation and they carry loads of different types of ball nut with little info for the noob on what makes them different(also many have very similar prices so that makes it even more confussing :)

Stuart

p.s. I found a referance to an faq on this site about stepper choice but i havn't been able to find it using the search box.