Re: How hard to rotate should preloaded ballnuts be, anyway?

The ballnuts should turn freely without any gritty feel.
If you can, submerse the whole ballscrew/ballnut assembly in
a solvent and run the ball nut back and forth to flush
any foriegn particles out. It could be hardened grease
combined with metal particles causing the problem.
This method is recomended by Bridgeport in their BOSS CNC
manual to flush the ballscrews.

Scott



--- In CAD_CAM_EDM_DRO@yahoogroups.com, Abby Katt
<cncgroupnospam2@...> wrote:

>
> Howdy Folks,
>
> I'm recomissioning a neolithic ORAC CNC lathe with modern CNC-controls
> (Mach3/new electronics etc) but in cleaning it up have run into a
> mechanical conundrum. The ballscrew along the long-axis is really stiff
> and gritty to turn, I've been cleaning it up with WD40, but so far

to no

> avail. I'm beginning to come to one of those deadly-fatal conclusions
> where I give up and let all the little balls out...
>
> My question is - how hard is to to rotate by hand preloaded ballscrews?
> (I assume this thing is preloaded, it has a massive ballnut) It has

some

> screws on the tubes through which the balls recirculate. Is it easy to
> open this and remove/clear/reinstall the balls, or is this just
> spherical-based-madness?
>
> The mounting block is also under tension, and also quite hard to turn..
> how tight should this really be?
>
> Oh, I have some pics of it here too:
> http://www.silverkatt.co.uk/Lathe/Default.aspx?Page=2
>
> BTW> This machine has been in storage for 10+ years...
>
> Regards,
> Abby
>