tool-man
Member
Steve's excellent library article http://content.penturners.org/articl...ressurepot.pdf was my inspiration for getting and modifying a Harbor Freight paint pot. I have a couple of tips and want to share a couple of modifications that I made:
- Notice that the "new" style pot does not have welded connections to the lid. Instead the factory used two-piece fittings on the lid. They screw together from the top and bottom side of the lid. DO NOT REMOVE THESE FITTINGS - there is no need.
- As noted in another thread, all fittings on this pot are glued together at the factory with some very tough epoxy-like stuff. Use a propane torch and carefully heat the fitting to be removed. Try to avoid heating the fitting that is directly on the lid. After 30 seconds or so of torch heating the fitting will loosen easily.
- The first picture is the top of the lid after removal of unneeded topside fittings. The second is the underside.
- The third picture shows my inlet pressure side configuration. The new parts are laid out disconnected to show each type of fitting I used. All threads are 1/4" NPT. Starting at the bottom of the picture is a coupler (which screws into the threaded lid fitting that was left in place) and then a 4 way cross - to the right is a pressure safety valve - on top a dual vacuum and pressure gauge, and to the left a cutoff valve. To the left of the cutoff valve is an air line quick connect fitting.
- My vacuum side is not in operation yet so the other hole in the lid is temporarily plugged. Notice that my gauge is a dual function vacuum/pressure gauge and is connected to the pot at all times. It will monitor either vacuum or pressure in the pot without the need to open and close any valves.
- I do not have a regulator on the pot because my compressor has its own regulator (most do). I set the regulator to whatever pressure I want in the pot and connect my air hose to the quick connect fitting and open the valve. The desired pressure is achieved pretty quickly - then I close the valve and disconnect my air line. My pot pressure drops about 10 psi overnight. It is a simple matter to reconnect the air hose, open the valve and top off the pressure in the pot.
- Picture 4 shows the final assembly. I have pressurized the pot, closed the shut off valve, and disconnected the hose. You can see it is holding at 30 psi.