We had a Spindle cooling fan overtemp alarm back last spring, Maintenance replaced it and all was well until this week when it did it again, The operator opened up the end of the machine and put a floor fan blowing on the Spindle cooling fan and continued running.... It seems to be when we are making heavier cuts that this happens.

Now the alarm is the Spindle cooling fan itself not the spindle, there is a thermal switch in the Spindle cooling fan motor that is tied to a input. We have plenty of air flow to cool the spindle.... everything seems normal no other high temps.... just the little Spindle cooling fan

Myself and the maintenance manager think that something weird must be going on... There is no way we should have to replace the Spindle cooling fan again...


Has anybody else had this issue? I am thinking a power quality issue (internally to the machine) or a magnetic field from the spindle affecting the Spindle cooling fan.

Mazak said last year that they have not seen many of these Spindle cooling fan go bad...

thanks