I have the new IS510 in place and it looks good, the test file cut well. I'm trying to get an idea for how much air usage the spindle should pulling, my 40 gallon 2 stage 3hp air compressor is kicking on about every 6 minutes (I calculated about 2 CFM constant air usage from the spindle based on the pressure drop from start/stop). Air constantly blows out the bottom of the spindle, not from the taper, and yes I checked when the spindle fan was off. Is this for the bearing to keep them pressurized so that nothing gets into them and should it be using this much air or is something else happening? It draws the same amount of air whether a tool is in the taper or not (I clocked the compressor and verified the start/ stop pressures).