I am really struggling with a problem and I have exhausted all ideas on how to troubleshoot the issue. I've replaced everything I can possibly think of and I don't know what to do, I am desperate...
The problem I am having is that I am getting what appears to be a reaction all over the first layer of clearcoat. As soon as I lay the first layer down I can see it react almost like its pinholes, or gassing reaction and excessive trash clumps. If I pile a second coat on, it helps, however it still looks bad. Then after about 2 hours of curing (air dry) I am getting micro pinholes all through the part consistently and dieback. I have tried several different brands of clearcoat, some are worse than others but the same problem happens no matter the brand.
I have zero issues spraying primer, basecoat or anything else. Its only the clearcoat. I have also narrowed it down to only the clearcoat process that is giving me the problem. If I get a metal can or a factory painted part and sand it, then clearcoat it I can replicate it everytime. The reaction is uniform all throughtout the part, not in sections. Black painted surface it stands out the most...
Even if I just spray 1 coat and leave it, I still get the dieback and reaction all throughout.
I've tried different methods of cleaning the parts from wax and grease remover to isopropyl alcohol/water mix. Same results.
I keep spending more and more money trying to solve the problem and I am not making any progress. And as of today I am out of ideas on what else to try...Attached are some pictures of my setup. I am painting small items.
Its a 2Hp 20 gallon oil-less compressor. I have the compressor running to 50 ft of copper vertical lines and drops with drain valves. I then bought a Sharpe 3 stage Desiccant system. I purchased a LPH400-LV with 1.4 tip thinking I was overatomoizing the clear coat however this did not solve the problem. The LPH80 is the perfect size for what I am spraying small parts...
I thought maybe it was the paint booth fan, I tried spraying with the fan running, without fan running and every possible combination in between. No difference.
The temperature is always 65-70 degrees and humidity is always low 30% range.
I've also given the clearcoat plenty of flash time, i've even tried as long as 45 minutes between coats. No improvement...




First Coat Clear
https://www.youtube.com/watch?v=aIbCwku1Ca4
Second Coat Clear
https://www.youtube.com/watch?v=IVOiU03PY48
Total dieback.
https://www.youtube.com/watch?v=-2WYew6p9n4