Help with contaminant ID

C

Chuck Nukem

Promoted Users
Good evening guys. I am in the middle of this project and I seem to be having trouble with contaminants while spraying base. My set up is:
80 gallon 2 stage
refridgerated dryer
particulate filter/water trap
new hose
gun regulator
disposable ball filter
gun

I seem to be getting little fish eyes when I spray base for some reason. I wiped the card down with wax and grease remover. Epoxy went down just fine last night with the same set up. Any ideas where this might be coming from?
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I would do the following:
Remove and throw the disposable ball filter away.
Completely tear down and clean the gun.

I have seen this type of contamination before and it came from the disposable dessicant cartridge breaking down. The gun was full of bits of crap. Once completely cleaned, the problem went away.

That's my $.03

John
 
Thanks for the reply John. I tried cleaning out the gun and removing the filter without much change.

I have tried different filter and hose arrangements and it all yields similar results. Scratching my head here....

If I blow air out of the gun for an extended length (say 30 seconds) I don't show any visible condensation forming on a paper towel.

The hoses I am using are brand new from Harbor Freight. Maybe that is the issue?

The epoxy laid down fine last night...
 
What is your particulate filter and water trap set up? Brand? Age? Post a picture? Could be coming from there.
 

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picked this up yesterday

also have one of these on it

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Harbor Freight buys their top quality tools from the same factories that supply our competitors. We cut out the middleman and pass the savings to you!
www.harborfreight.com www.harborfreight.com

I have never run an oil lubricator on any of the lines I have
 
Nothing worse than these types of problems. Try eliminating common denominators one at a time. Try a different base, reducer, tack rag, mix cups, air hose, etc. One red flag for me is the epoxy going on fine, and the base fisheyeing. This tends to make me think the base or basecoat reducer is contaminated. Base usually does not fisheye easily, and if it was your air system the epoxy would fisheye easier than the base, unless the epoxy had some type of contamination land on it overnight before base. Good luck figuring it out.
 
I am spraying SPI black base with very slow reducer @ 80 deg today

So far I have tried
Cleaning gun with lacquer thinner vs acetone
Different guns
Different hoses
Different compressor at friends house
w & w/o air dryer
Cleaned out air dryer fins to make sure everything is working (air inlet line is cold)
w & w/o bulb filter
PPG Deltron base and 885 reducer had same flaw

Could my mixing sticks and paper filters be contaminating it?

No silicone used near by as far as I know
 
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Anything that touches your paint or surface could cause it, including sticks, strainers, or mix cups. Did you happen to wipe these panels with the same type of rags and same wax & grease remover? Did it have proper flash after wiping? 700, if not flashed enough, can cause a similar looking defect. Probably not causing it, but that panel looks to be sprayed extremely wet with low air pressure, which, if there is some contamination there, will accentuate it.
 
There were a few cards which got sprayed maybe 5 min after wiping with 710 solvent based. Tried another few cards after waiting 15 min. I have not tried 700 on it yet. That was the first card I sprayed and I definitely overdid the volume after I saw the dots to see if they would disappear.

texasking said:
Anything that touches your paint or surface could cause it, including sticks, strainers, or mix cups. Did you happen to wipe these panels with the same type of rags and same wax & grease remover? Did it have proper flash after wiping? 700, if not flashed enough, can cause a similar looking defect. Probably not causing it, but that panel looks to be sprayed extremely wet with low air pressure, which, if there is some contamination there, will accentuate it.
Click to expand...
 
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Sometimes stuff comes from what we are wearing ( gloves, mask, paint suits, etc ) and also the vehicle itself.
 
No need for wax and grease remover on freshly sprayed epoxy (or anything else freshly sprayed) imho. Just looking for trouble.

Are you using microfiber cloths to wipe down wax and grease remover? This has been shown to cause problems.

Don
 
I haven't tried to hit a panel yet with base coat because I keep getting these fish eyes in the test cards. I ignored that omen a few days ago and the results were...disastrous.
I painted 2-3 coats of epoxy 1:1 over every panel and sanded them down to 600 to prepare for basecoat. I wiped down all panels with wax and grease 710 using paper shop towels, then tack rag.

At this point I'm thinking about going to a local store and getting a pint of paint mixed for me and tested with my gun in the store. Then take that same paint and set up home to spray on test cards here to see if maybe my sticks or cups contaminated my paint. I'm a little worried I might have contaminated my entire gallon. Especially since I now have the same problem with a ppg base which was good the last time I sprayed it.
 
Spray something cleaned with dawn & water & do not use shop towels or prep wipes you mentioned.
Bounty is fine just not the first or last couple on roll cause of glue they use.
 
I bought an aerosol spray set up to be able to test paint without running it through my rig.
I set up two sets of 4 cards so I can compare my rig vs the aerosol
no wax and grease
700 wax applied and wiped off and sprayed immediately (to try and replicate failure)
700 wax applied and wiped off and sprayed 15 min later
700 wax applied and wiped off and sprayed 60 min later

Every single one failed the same way

I took the aerosol can to the paint store and had them try on a card and it worked perfect....

Completely confused I took the aerosol sprayer back to my house and tried on a card....same flaw.....

Now I am really confused.
 
How does the environment compare between the paint store and your spraying area at home? Temp and humidity, etc.?

I remember reading over this post, Bob Hollinshead refers to an instance were deodorant caused an issue. I wonder if it is something similar on you or your clothes.
 
If not your clothes or deodorant (which would be really unusual) it's in the environment in or near where you spray. Chances are it's close to where you spray, although it could be coming from outside your immediate area. I go back to silicone contamination because it is so common and the stuff hangs in the air and gets everywhere. Silicone spray lube. Tire dressing, something treated with silicone dressing like your wife's car for example. Is your garage air conditioned or heated? Having you been running either lately? If so can you verify they are in proper working order? Could also be contamination from something a neighbor is doing. My gut says it's something inside your garage that is causing it though. Do you have kids? Have they been in or playing around the gargage when you are not there? Worst case clean the garage extremely thouroughly wiping down everything, mopping the floors, and walls etc. If I was stumped I might even start there. Spend a Saturday cleaning and tossing anything questionable and go from there. Also you'll want to get a fresh batch of sticks and strainers, wipes etc, bag them so you know they'll stay clean and use them for your next test. Using anything you have now runs the risk of already being contaminated.
Start in the garage or paint area and work outwards. Wish I had more to help you with, but that is all I can think of at the moment.
 
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