Company in Claremont California use to make oil bath air filters that work very well with these steam air compressors. Santa Fe used them on their engines as well as a lot of other companies. A couple of years ago the city of Claremont forced them out because they wanted the property for high rise residential and shopping. This is what you see happening everywhere in the USA. Vortox relocated to Australia where they set up and still make the oilbath air filters. They are really great filters for this extreme survice we see. You can find them at www.Vortox.com