spindle start-up

[poster]

I have a Rh33 w/ a 8000rpm spindle.
The start-up procedure for the spindle is as follows

Run the spindle at 50% of the maximum RPM for 10 minutes.
Measure temperature at various locations on the front of the spindle cartridge.
Be careful as the spindle is running! If at any time during the spindle run-in procedure the temperature reaches 140 degrees Fahrenheit or 60 degrees Celsius, stop the spindle and allow it to cool to room temperature. Resume the procedure at the point of the procedure it was halted.

what exactly does this do? aren't the bearings sealed? also if it heats up after 9 min. i can just resume it for one more minute after it cools off, and it will be o.k.?

I don't really understand exactly whats going on here?

[sportybob]

The spindle warm up procedure is so that the spindle has time to warm up before running at max RPM. Think of jumping in your Corvett and backing out the driveway and running 1st gear to redline. You most likley would not do it, you would let the motor warm up befor "nailing the hammer down".

Checking the spindle tep is part of the "1st run in procedure " recommended by the spindle Manufacturer. If you read further down the run in procedure it recommends that the warm up be done when ever the spindle has set idlefor more then 1 hour, In one hour it has had time to cool off.
If you check most machine tool manufacturers recommend and some demand that spindle warm ups be done. It helps protect an expensive piece of hardardware.
you can write a small text program to do this for you after homeing the machine ie:
O9999 (spindle warm up)
S4000 M3 (sets 4000 rpm in CW)
G4P600 (sets a count down timer for 600 seconds- 10 minutes)
S0 (sets zero RPM)
M30 (ends program)

While you are at it maybe add some X, Y and Z axis moves to warm them up as well.
N1 G1 F100 (Sets line 1 with 100ipm)
X0 Y0 Z0 (Sends all axis to 0)
X-70 Y -30 Z -20 (sends all axis to travel limits at the same time)
gotoN1 (loops back to line one)

start warm up, go make coffee and come back to a spindle/ machine that is "ready" to run.

IMO- The above is good practice for any machine.

Sportybob