Re: Re: What makes a machine CNC ready?

> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "lcdpublishing"
> <lcdpublishing@...> wrote:
> >
> > That's a pretty bold statement.....
>
> >
> > Why would that ball screw fail in 5 years? I have never seen any
> > references published that state the life span of a ball screw is 5
> > years, 10 years, or 20 minutes.
>
> Ball screws have a rated service life. I expressed it as cup half
> empty, instead of cup half full. ;-)
>
> Some Thompson ball screws have a 2.1 million inch rated service life
>
> I estimated this as 3 hr/wk at 50 ipm = 9000 inches per week
>
> 5 years at 50 wks per year and 9000 inches per week = 2.25 million
> inches.
>
> Several other US manufacturers rate their ball screw service life at
> 1,000,000 inches. If you read the literature published by the
> manufacturers, you can see the detail of how they predict service
> life.
>
> Fred Smith -

So what's Kerks service life ?

Then work out service life verus cost to get an equal comparison.

John S.