I need an adapter to go from the standard scuba regulator LP port to a 1/4-in NPT thread. My intention is to use a scuba cylinder (with an old regulator) to drive an airbrush. I have a regulator that will reduce the pressure from the scuba IP to the 20-40 psi needed for the airbrush. Problem is all of the airbrush fittings are 1/4-inch NPT. Suggestions are appreciated.