Preload 8000 RPM spindle Arrow 500

[Ninus]

Hello everybody, unfortunately I have to replace main spindle bearings on this machine (built in 1998 ), afther to adjust the preload start spindle run out at 500 rpm and in five minutes some click noise appears and afther several checks I understand that the top bearing have been damaged. Of course I follow the drawings included on the machine to asembly but it seems that I do something wrong
Does somebody have any instructions over how to aply the preload, in this case I adjust checking fo spindle movement in axial direction 0,005 or less
Well thanks to all
Hope good news.

Ninus

[scudzuki]

The preload on the grease lubed bearings in my 6000 RPM Arrow 500 spindle is set by the inner and outer spacers and should not require adjustment provided the bearings are oriented correctly. Is it possible you damaged the bearing driving it into the bearing bore?

Joe

[DSIF]

There are so many factors that go into rebuilding a spindle properly. The most common cause of failure is too much grease. Most of the one's I have done take no more than 2.5cc's. Speaking of grease,did you use Kluber NBU15? If not,that was your biggest mistake. As for pre-load,I use an indicator and adjust to ~.0005" play when cold on the bench.
Also everything MUST be CLEAN!!!(Including your hands).
Dan

[Ninus]

Thanks to both for your answers, especially to Dan, you are rigth, my hands have to be clean, I think there was be the problem.
Tomorrow I have to go to replace again, I'll tel you something.
Thanks to both again

Ninus