Quote:
Originally Posted by Lynn Eades
Tony, Can you give us a run down on setting up a gun.
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Sure, Lyn. There's no trick, it's just a matter of finding the right setting for each combination of gun and paint type. Acrylic paint will require entirely different settings to enamel, different again to 2-pack, etc. If, like me, you paint outside, temperature, wind, direct sunlight or shade, and paint type all combine in dictating the end results. Might be easier to explain if I use illustrations and possibly demonstrate what the various adjustments do. On Sunday I will find a suitable bit of metal to paint on, and I'm sure I have some usable paint that I won't use for anything, which I can put into the gun for the purpose. Bear with me until then. I recommend you find a nice big panel to practice spraying on, and experiment with changing gun settings and air flow rate, using the type of paint you intend to use for the 'real' job.
There are some things I will take as a given. Always follow manufacturers instructions, with regards to thinning ratio, and hardener additive, if applicable. Always clean the spray gun and pot immediately after you finish spraying. A dirty or partially blocked gun or nozzle will never give a good result. Usually any blockage can be cleared, but this may involve immersion of the gun for a period of time. I do the first clean of the gun with a small quantity of the thinner or reducer which is applicable to the paint which had gone through the gun, then another, more thorough, clean with thinners which I know as either "G.P thinner (general purpose) or "Gun Wash". As the name suggests, the latter is only good for cleanup of equipment, not for thinning paint. I recommend buying a multi scale measuring stick AND graduated (marked, not received a qualification!) mixing cup. Most cups come in a range of sizes, to suit any quantity of paint desired, and should be clear so you can watch the level of material from the outside. They usually have several different ratios marked on the sides. Mine I think have six ratios 1:1, 1:2, 1:3,........ you get the idea. The measurements usually include the ratio or hardener, if it is required. I cannot overstate the importance of mixing ratios. I know it is a pretty basic consideration, but you would be surprised how often i hear someone say they mix by 'sight' or close enough. Every part must be exact, at least until you know what you can achieve by altering the ratios. I won't go into that for now. Best left for later.
I'll have a little play on Sunday, and post some info with photos. As i said before, there is no great mysteries, just some principles which must be observed, no matter what type of paint you are using. Those principles, once fully considered, will get a good result every single time.
I recommend everyone wanting to refine their skills prior to the real paint job, to get their hands on a nice large vehicle panel. A decent size bonnet / hood would be perfect to practice on. Stand it on it's side, and spray your practice when the panel is vertical. There is no challenge in spraying a panel when it is laying horizontal. Paint won't run off it like it will when it is standing vertically. You will want to ensure you can avoid paint runs, so make your practice reflect the conditions you will be subjected to with the real thing. Once you can successfully spray without dry spots or runs in the paint, repeat the test again with straight thinners, no paint. If you can apply thinners evenly and it doesn't run, then you have achieved your goal. Any spray job after that should be a walk in the park, and you will be ready for the task at hand. It will make more sense when I demonstrate, trust me.
Excuse any spelling mistakes in the above. I don't have my glasses on!