Clearcoat boiling/solvent trapping/micro bubbles?

Only wiping base with a tack rag. I even bought an Neutralizer AC static gun thinking maybe my tack rags were causing problems. That didn't work so I winded up returning it.

Normally after I basecoat, I clear after an hour. I thought that was the problem so I eliminated that by basecoating a part. I let it sit for 3 days then shot clear over it. It did the same thing they pinholes showing up everywhere.

When wiping down with isopropyl alchoal/water mix, i'm waiting about 5-10 minutes?

I've narrowed it down the the clearcoating process.

This may sound weird but the paint booth I am using has filters that have 30 lbs of carbon in them that absorb the VOC's. That wouldn't be causing some kinda reaction of some sort?
 
I'm going to get that devilbiss desiccant snake today and one of them screw orange gun paper filters. I figure that would eliminate the moisture issue combined with the rest of the setup I have.

Other then that I just dont know what to do. Invest in some more wetsand and buffing equipment ughhh
 
10 mins are to soon when water involved, but you said happened when you let set 3 days.
That would cause the low solids clears to die back.

So your choices are.
All solvents must be 70, and I said all.
Air at the wall needs to be 125 min.
No strainers in gun or cup.
Water in the hose.
Trust you not using detail rags to clean with


The filters do nothing.
 
This is just a shot in the dark but if I use the fast activator. It will dieback completely and loss gloss. The the medium and slow looks great just those pinholes.
 
Barry said:
All solvents must be 70, and I said all.
Click to expand...

@ebaypdllc
Get the temps in your room up or you are wasting your time. What Barry said is not a suggestion. You need all the products and the room temp at 70. 61-64 degrees is not good enough. Heating the clear is not a substitute for room temp at 70 and all products at room temp when you are spraying. Do what you have to, to achieve that.
I still say long term you need the water and oil coalescer's in front of the dryer. And you can't neccesarily rely on the indicator on the dryer. Seen that enough to know.
 
I like your setup, the idea of having something like this in a basement never occurred to me. At least this appears to be in a basement. If so I assume its unfinished with maybe 1 or 2 heat runs for the entire basement. I have a basement in my house that is finished with multiple heat runs and speaking only from a temperature standpoint I wouldn't dream of trying to paint in the temps that my basement is at, which are very similar to what you have. Its possible you have more than just one cause to figure out, but until you get the temps up to around 70 your going to have a hard time.

Here is a good example for something that might work well for you if indeed you are in a basement. Use it to warm the product and the room at the same time.

http://www.spiuserforum.com/index.php?threads/unconventional-paint-warmer.6824/#post-73226
 
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A motor guard m-60 in front of the desiccant is the way to go, I am guessing the air hose has some contamination inside of it. What cloths are you using to wipe down with? A guy that lives near me uses anything from hospital rags to paper towels to prep with and he always has problems. I am anxiously waiting for the cure to your problems.
 
Yea it's in a basement as a temporary setup. Going to be building a workshop detached from house to work in. I only paint small items and the booth works great. It sucks up all the overspray through the bottom. Behind the paint pockets filters are 3 heavy duty 10 lb carbon filter. At top is another pleated carbon filter and an intake filter. Amazing what carbon filtration can do. You don't smell anything and it has a nice curtain system to prevent overspray...
 
Going to try again tonight...Dam sleep schedule all messed up slept the whole day away ugh... I upped the temperature upstairs thermostat to 72. Its 24 degrees outside right now.

The booth fan is fairly strong 5500 CFM that is pulling all the air from upstairs down into the basement so its warming up the area down there if let it run... I can also add a heater down there which should get it above 75 to 80 easily.

I have a large utility sink that I installed for prepping/cleaning and wetsanding parts. I have hot water in a bucket warming up the Clearcoat and Hardener. I put them in a large sandwich bag so the water doesnt touch the cans.

Panel temperature of the part is currently at 71. The air coming out of the booth is around 73. When I close up the curtain system which is 12'x12' it gets warmer in there also quick...





 
I just did another test. I got the temperature to about 75 Degrees in my painting area. Panel temp was 75 degrees. Clearcoat and hardener was warm about 90 degrees when mixed.

As per Barry suggestion I changed the Air regulator on the DevilBiss QC3 to 120 PSI and regulated at the gun down to 20 PSI. Iwata LPH80 1.2 with 2 1/2 turns fluid and fan wide open.

On my first coat there was immediate reaction. Here is a video shot 1 minute after overspray was gone.


Here is a second video shot about 1 minute after coat #2.

This tells me that its some kinda moisture problem or contamination?
 
I feel for you and your head is spinning but just asking have you tried spraying a old gallon can or other metal maybe just clean with water base cleaner and shoot see what happens ?
 
This part cured with the micro pinholes also and the ugly finish that showed up on the first coat.

I've narrowed it down to the clearcoat process only. I eliminated the temperature issue. Its not humidity or wetting the floor.

Only thing that makes sense is the airline. I thought my airline setup was done correctly with the 50' of copper lines and drops to the QC3 filter.

I'm going to buy a different filtration system and add a snake before my spray gun. I'm out of options on what else to try.

Devilbiss CT Plus Stage 5

https://www.amazon.com/dp/B0013FLFKA/ref=dp_cerb_3

Deviliss DAD-PRO

https://www.autorefinishdevilbiss.c...ion/dad-pro-desiccant-drying-system.aspx.aspx
 
Here s my issue, go through this daily, be it gun adjustment, or why am I using 15% more clear than I was with other brand.

I was not going to answer again as I felt I was not getting the full story and was wasting my time.

NOW you post this:
"40 PSI. The gun I used setup was Iwata LPH80 1.2. 2 1/2 turns fluid, wide open fan."

First, the 1.2 is not going to work, and 2nd 40 is to much air for a 1.2, so the option is this.
A 1.4 like we state over and over
And set air at 26 to 28 with the trigger pulled.
This could very well be the water problem as over atomizing the clear.
 
Hey Barry...I've tried everything. The gun i'm using is Iwata LPH80 which says 6-14 PSI. I tried spraying at 14 PSI but it leaves too much orange peel. 20 is the sweet spot...I did experiment and try 28 PSI because I saw some people on Youtube with that adjustment but there is no difference.

I tried spraying with a different gun with 1.4 tip, no difference.

I think you misread what I wrote. The QC3 is the desiccant that has a pressure gauge. I had it set at 40 PSI "at the wall", which then I regulate my gun with a regulator to 20 PSI for clear. This time around I changed the pressure to 120 at "the wall". But regulated down to 20 PSI at the gun.

Its almost as if putting the QC3 at 120 PSI made my problems worse. I'm wondering if vapor is blasting through it or whatever the contamination is.
 
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I think I might have the answer. I just bought a Tsunami Membrane Drying system it will be here in few days. In the product demo he said that "the lower the pressure you regulate, the better performance you will get for dryness of your air".

I regulated from 40PSI to 120PSI on that Desiccant I currently have and that's when major issues showed up right away on first coat.

I'm wondering if I can set my Air Compressor regulator to 20PSI. Then to the desiccant regulator at 20PSI then 20PSI at spray gun to do a test so see if I see an improvement. If there is big improvement then that confirms water vapor.

Regulated that low should create almost no water according to this video.

 
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are you sure this is air bubbles and not just dirt and dust nibs getting in the paint? i would say moisture or contamination from your air supply or its just dirt landing in the wet clear. i have an lph 80 in a 1.0 tip and 2 minijets in 1.2 and 1.4. i have shot countless gallons of universal clear through them over the past 20 years and never had a problem with tip size causing an issue. hell i have sprayed it through an airbrush more times than i can count and that tip is .03. i have sprayed it in 50 deg weather to 100 deg. 50%-100% humidity and never a problem other than dust nibs in the clear. like i said though i have never shot the production clear. 95% i am spraying the universal. in general though, the clear isnt really as finicky as what it appears by reading your issues. considering your other clear is dying back then i would say you have a moisture issue. you dont even have to have physical droplets of water. your air supply could just have a super high humidy to it. the cat sucks that up when you spray the clear changing the curing properties. more moisture cause curing to speed way up.
 
They look like nibs but under magnification they look like pieces of fishing line or clear worms which I believe is isocyanate clumping.

This last job I did with the video I never had an issue like that before with contamination like that all over the part. The only variable that changed was I heated the area and I upped the pressure on the Desiccant regulator from 40PSI to 120PSI.

I'm wondering if that extra PSI is blasting the water vapor through my airline that got to spray gun. Which I believe would verify its moisture problem.

I got my fingers crossed...
 
Try cheap new hose from your new filters to gun & clean gun thoroughly before going further.
If old hose & gun got contaminated, all your new filters mean squat.
Ard tell me you are only using spi reducer to clean gun & reduce.
Last time i got pinholes was from puddling uvc on flat taillights & using up old fast activator.
I also had your problem way back when i used cheap local reducer, not spi. Learned that.
 
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