Just wanted to share a cool product that I use to make sure no moisture or oil goes thru my laser cutter. I use a FishEye filter. Have been using them for painting for a few years now and have one installed on my Boss laser engraver. Always have clean dry air. Check them out on the web or at Coast Airbrush which is where I bought mine. I run filter it before regulating it down for the laser cutter. I run very low air pressure about (10-20psi) Just enough to keep the lens clean.
https://www.fisheyefilter.com/
https://www.coastairbrush.com/