Delrin is a dream on my swiss. I am making some .26"dia by 2.25" long parts and they scream. We do not run coolant at all. The residual oil left from the bar feed is the only oil we need to clean off the part. Delrin parts should be cleaning in pure alcohol because it will absorb water and swell. The only problem with holding .0005 would be that the parts do shrink and grow with the change in temperature from machining. In my experience the shrink about .002 on the diameter from hot off the machine to ambient.
Chip control will be the only problem, use super high feeds and air blasts to clear the chip. Also the cabinet air will make your eyes burn similar to chopping an onion due to the acetic acid that is off gassing from the machined parts.