Re: [CAD_CAM_EDM_DRO] Re: What makes a machine CNC ready?

On Fri, 30 Jun 2006 11:58:08 -0000, you wrote:

>--- In CAD_CAM_EDM_DRO@yahoogroups.com, Steve Blackmore <steve@...>
>wrote:
>
>> 0.001 per foot is not that precise, it's grade 3. That's 25.4um per
>> foot, the screws I use are 0.052um per foot (grade 7;) and are
>the ones
>> priced here.
>>
>> As an example..
>>
>> 16x4mm is $32 per foot, $91 for the screw and $18 for the seals.
>
>Here is an example of a typical ball screw that a home shop user
>might use( many do as they are available and prices are posted):
>
>http://www.homeshopcnc.com/page3.html
>
>A 6 foot screw (5/8 - .2) with 2 nuts would be $140

And not very good tolerances either! No wonder you need two nuts with
rated backlash of .001-.004 inches, I'd rate them as "all thread
quality". :(

>In an equivalent 1/2-10, 2 start acme thread, with a single anti-
>backlash, wear compensating nut ($32), the total would be $85.
>

Is that for the Kerk screw you were telling us all about or just some
nondescript make?

Steve Blackmore
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