Re: Balllscrew time!

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Abby Katt" <cnc@a...> wrote:

> Hi folks,
>
> I was wondering if anyone remembered the links to the pages that

showed an

> asian benchtop mill having it's leadscrews replaced by ballscrews? I

finally

> managed to get some 2nd hand... (Saved a ton of money, thanks Rab if

you're

> reading this!)
>
> Also, I was thinking of using the original bearing blocks that come

with the

> mill, but when I measured the diameter of the holes which take the
> ball-bearings, I noticed they had an odd sized value (the rest of

the mill

> is metric).. Since I can get only standard 30mm bearings, not 30.5mm

ones..

> I was wondering how closely they need to be matched up? Is it the

point for

> the ballbearings to have some room so it can compensante for the

load, or

> does it need to be a nice tight fit?
>
> Thanks again,
> I'll post pics as it gets on...
>
> ~Abby

Abby,
They need to be a push fit to a light press in fit.
Are you sure they are 30.5 as it's a weird size not even imperial.

Did actual ball races fit in these blocks or were they machined out
for thrust bearings ?

Without knowing the size of the ballscrews would it be possible to
bore the housings out to the next size OD bearing ?

John S.