Re: [CAD_CAM_EDM_DRO] PLEASE HELP in cleanup of bridgeport

> > >
> > >Next step is a real good cleaning. The one hand crank on the Y axis
> > >(left-right?) doesn't feel very smooth and I am thinking of the
> > >graphite in and on the ball screws. Yes, its all over, and up under
> > >the table on the screws. What is the best way to clean these ball
> > >screws. Now I am going to guess - DONT TAKE IT APART! If my guess is
> > >true then does one just flush it out, wipeing down the exposed shaft
> > >and moving the nut from one side to the other, repeating this till
> > >its all cleaned out?
>
> I had a new ball screw that was "crunchy". I could see little bits of metal
> on the screw after running the screw back and forth. I finally figured out
> that greasing the screw with axle grease would trap the grit and make it
> stick to the screw. I spent a whole evening greasing the screw, running it
> fully through the nut, and then wiping all the debris off the screw and
> regreasing for a return trip. It finally removed all the foreign materials
> from the screw and nut, and it now runs completely free, with no crunching!

Sounds like a good idea if one wants to avoid taking the screw apart.
Incidentally, dismantaling a ball nut is not all that bad, provided
you work close to floor lever rather than at bench height. Find an
old blanket and put it on the floor. Sit in the middle of the
blanket. If you drop a ball, stand up very slowly and look around.
There are various tricks for putting the balls back in - feeding them
in through the return channel, using grease to hold them, or my
favorite which is loading them in the end of the thread with a mandrel
(rod or cylinder of root diameter) through the nut which you back out
just enough to push the balls past the return tube's takeup spur.
Then you carefully turn the screw into the nut, pushing out the
mandrel.

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
http://www.mdc.net/~stratton
NEW PHONE NUMBER: (617) 628-1062 home, 253-2606 MIT