Usage Advice
1). First off, the regulator and gauge on the pressure cup is only for regulating the paint pressure, not the gun air atomising pressure.
2). The gun atomising air pressure is regulated initially at the compressor or if you have it, a separate air filter regulator. so if you set this at say 15 psi or 1 bar, this will bypass the pressure cup regulator and you will have roughly 15 psi (1 bar) atomising pressure at the gun.
3). When setting up a pressure gun, a good rule of thumb for setting the pot pressure is to turn off the gun atomising air at the gun itself (screw located at the air inlet on the gun). So should be now that even though you have air going to the pressure cup from the compressor it will bypass the pressure cup and run up to the gun. But as you have turned the air off at the gun, when you pull the trigger no air will come out of the front of the gun.
4). With paint in the pressure cup and the lid screwed on firmly, increase the pot air pressure incrementally. Holding the gun as you would when spraying (perpendicular to the wall), so that when you pull the gun trigger you get a stream of paint horizontal for about 5 to 6 inches, which then starts to drop away . If after doing this, and you do not have enough paint coming out of the gun when you spray, then you can increase the pressure cup a bit more. But should you still not have an enough paint you will then need to go up a fluid nozzle/needle size or two. The 5 to 6 inch rule is such that if you have the cup pressure to high, then the velocity of the paint as it comes out of the front of the gun is too fast for the gun to satisfactory atomise the paint.
5). Fluid nozzle selection. Generally the thicker the paint, then like airless you need a bigger nozzle. Nozzle sizes range from 1.1 mm (solvent based paints and lacquers) to 2.2mm (non thinned water based primers). 1.8 mm fluid nozzle and above needs the bigger air cap/nozzle. 1.1 to 1.5 mm fluid nozzles use the same air cap.
6). If using a variety of different primer and top coat paints then it is best to have a selection of the fluid nozzle and air nozzle combinations. Just like with airless or AAA you have different size tips for different paints.
7). With the Iwata (and all spray guns) always keep the air pressure as low as possible. Start with low pressure then increase until you get a good finish. The more air pressure the lower the transfer efficiency (wastes more paint).
8). Horses for courses. Compressed air Conventional, LVLP or Compliant guns have a greater range of paints that they can atomise over HVLP turbine systems. It is because they can go above the legal HVLP air pressure limit of 10 psi (0.7 bar) at the gun air nozzle. But because they can, it means the transfer efficiency will go down as the air pressure goes up. So as point 5, keep it as low as possible.
Sprayman UK 2L Pressure Cup + 1.4 M Air and Paint Hose Set – SPUK034.
Need to chat call Sprayman UK on 01543 496 289.