Originally Posted by
planebuilder
I have been using a Porter Cable 7518 for many years on my CNC gantry table. I have rebuilt it 3 times, new bearings each time, I don't think it's worth rebuilding again, getting loose and runout is increasing.
I cut wood, plastic, and mostly 6061T6 thin sheet (.020) up to 1" plate (multi pass). Most work is with 1/4" 2F bits @21,00 rpm. I'm thinking it's time to buy a spindle. I have 220 single phase power.
I'm thinking ceramic bearings, water cooled.
What G-Penny spindle size would you recommend, 2.2 kw or 3.5 kw to be as good or better than the PC7518?