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

Abby,

I wish the second picture in the second series shwoed BOTH seides of
the ballnut mounitng block...

Could yo give us a pic of th eother end of the nut mounting assembly
please?

Anyways, it appears that you have TWO ballnuts; each threaded into
opposite sides of a single mounting block. If so, this is pretty
good news...

While I wait for confirmation/picture; you should be able to
determin if the headstock end bearing assembly is binding as it can
be rotated without involving the nuts... Is it okay?

Thank you in advance, Hope this helps,

Ballendo

P.S. If one is careful, re-installing balls is not as hard as you
might think. You may not have to; but don't think of it as a
horrible prospect. It can even be a bit fun; if yo have the right
mindset. As another mentioned (Harko?) you DO need to determine
whether ALL the balls are the same diameter, or of two different
ones. AND you should do ALL ballnut repair stting ON THE FLOOR, in
the MIDDLE of a LARGE WHITE sheet, with a couple blankets--or carpet-
-underneath. This way if you DO lose a ball, itr won't BOUNCE, and
it won't be hard to find. Wear non "fussy" clothes, so you don't
lose them amongst your own clothing. Been there, done that.

Let's get a pic, and see how hard this might--not--be.

--- 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
>