POR15 spray problem

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rusmannx

rusmannx

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I'm posting these for a friend of mine.
We spent a chunk of time yesterday stripping the hood on his 40. Afterwards he prepped the metal using PORs Maring Clean and then PORs Metal Ready following the instructions to the letter.

Once prepped we had a friend of ours who used to be a painter come and spray the hood. What we got were less than amazing results. Again, the spraying was done exactly as per the POR instructions.

You can see these little circles all over the surface. It is like some little spec of something pushed the POR away from it creating a tiny crator. These circles are from pin-head size up to maybe 1/4" in diameter.

Our air supply runs throughout the garage in copper tubing and through a filter/regulator that is also supposed to extract any moisture from the line.

Any ideas?
por1.webp
por2.webp
 
You can almost see the cloth marks from wipeing,Ill bet you used an old rag that had been washed in Tide or something simular .Most paints do not like the phospheras.A final wipeing with a Final Wipe solution should have solved that .You will have to sand it smooth and put a thick primer coat down now.Sand it and then top coat it with a clear base.A couple drops of Smoothy will help on the final coat
 
the cloth we used to wipe down were new and have never been washed. they were not bought specifically for paint prep, though they were lint free. i guess we'll have to get some legit cloth for when we do the rest.
i think those are sand marks however.
thank you for your input :)
 
You will find out if the chemical reaction is still there when you primer it.A finnal wipe should take care of it though. Ive also screwed up when i used an air hose that I was useing on an unfiltered system and plugged it into the filter thinking all was good,It wasn,t and I had fish eyes like yours all because of the hose.
 
contamination

It does look like contam of some sort google on paint and fisheyes

normally for painting I would use an in line dessicant at the connection to the gun also the filter at the compressor is not enough cause you get cooling and condensation in the line

the other thing is I have found even when I seem to think I've done everything right it is good to let everything sit for a good long while and make sure that all the solvents have vented off or water evaporated

On the other hand I am not sure I would bother with POR on the TUB and hood surfaces---Better off using it underneath

A good epoxy primer followed by a high build primer and paint should be more than enough and save the POR for underneath IMHO
 
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Looks like silicone or oil/grease contamination to me
Did you wipe it down with something like an anti-silicone wash and a strong lacquer thinner before the POR prep?
 
He used POR brand cleaners and prep stuff before the paint when down. The filter i have is at the regulator which is where the hose connects. there is no filter at the gun.... but not a bad idea.

we'll try to sand it down or something then start with a highbuild primer i guess. probably have to sand the primer too. damnit. we were going for quick and easy (not high quality), but this is unacceptable.

71FJ40 said:
Looks like silicone or oil/grease contamination to me
Did you wipe it down with something like an anti-silicone wash and a strong lacquer thinner before the POR prep?
Click to expand...
 
Poser said:
Are you using a last chance filter right at the air inlet for the spray gun?
Click to expand...


Looks like water in the mix.............to me.:meh:
 
Those pictures look strange. I manage an aircraft maintenance facility that also has a paint shop. We predominantly paint regional airline type aircraft. I'll have the guys look at the pictures in the morning and get their take on it. Keep in mind that POR has no UV protection by itself. You will need to use their clear or top coat it with something. If not, it will start to chalk in about 6 months or so.
 
the POR is getting primed and painted soon.

Damnit, i just thought of this. That copper leg is pretty new. i'm wondering if flux is in the system and got past the filter....
 
I see water and fisheye. The circles woth dots look like dust/dirt. I'm gusssing static discharge was crazy too? Wet down the floor an hour before hand and the charge should drop.
 
i didn't wet the floor. how can you tell there was static?
 
I used to own a paint company. Those fisheyes look like what you get when the static discharge pushes oil paint away from debris (and it's usually worse in low humidity/ high heat). The dots look like water in oil though.

Is por 15 oil based? If it is I'd dry that hose out before you try again.
 
POR has the following:
Diphenylmethane Diisocyanate
Naptha Petroleum
Carbon Black
Aluminum

we do have low humidity here. what do you mean by dry the hose out and how?
 
what kind of stupid world is this where expensive or fancy paints have to have perfect spraying conditions and cheap rattle-can garbage can be sprayed over dirty metal and last forever?

we kryloned my buddies 40 years ago and its help up just fine. sure it doesn't look great, but neither does this so far (and at 20 times the price).
i smell a conspiracy.
 
rusmannx said:
what kind of stupid world is this where expensive or fancy paints have to have perfect spraying conditions and cheap rattle-can garbage can be sprayed over dirty metal and last forever?

we kryloned my buddies 40 years ago and its help up just fine. sure it doesn't look great, but neither does this so far (and at 20 times the price).
i smell a conspiracy.
Click to expand...
Should have just gone to MAACO!;):bang::lol:
 
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