What does the top control knob do? This is a Binks M1-g spray gun. The bottom knob controls fluid but the top knob doesn't seem to make a difference on anything. I
Binks Trophy Series Spray Gun, HVLP, 1.0 mm Nozzle, 33H Air Cap | Spray Equipment & Service Center
HVLP Spray Guns - Binks
ECE Canada Limited.
Binks 10 Litre Zinc Plated Pressure Pot Package 2 from SprayDirect.co.uk