Spindle Break In Recomendations

[RJS100]

I just upgraded the spindle motor on my benchtop mill. Original max rpm was 3200. I have run many hours at 3000 rpm. The spindle's tapered roller bearings are rated for about 6000 rpm. I plan on running around 5000. I seem to recall something about breaking in bearings when running at new speeds. Do you have any recommendations?

[suntravel]

I would do nothing.
If it is cold in the shop do a few minutes warm up with 2000 rpm
When running first time 5000rpm keep an eye on the temperature of the spindle.

Uwe

[RJS100]

Thank you. Will do.