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Water Problem with Air Compressor

43K views 45 replies 10 participants last post by  71gtx 
#1 ·
Hello guys, I am pretty new to painting cars. I am working on a project spraying with a gravity feed gun. I have a craftsman vertical 33gallon air compressor. I purchased a craftsman water trap/filter and mounted it stratight off of the compressor before attempting spraying. I used a hose that has the hard plastic outer shell. Well, I got water bubbles heavily in the area I tested.

I then took a DA and ran it and noticed that water was coming out heavily, but no water is collecting in the water trap. i was told i need a rubber flex hose rather than the one i have, but why isn't water trapping in the first place? any tips on how to set this up to eliminate all water?

I was also told to mount the water trap higher than the compressor to help?
 
#27 ·
The reason I don't think that it is too heavy of a coat is this: The first light pass I had showed the "fish eyes" and adding more paint never improved them. As far as contamination this is what I did:

I wet sanded a previous water problem, cleaned with soap and water, cleaned heavily with metal prep, and finally went over the surface with a tack cloth.

Could too much hardener cause this? And would fish eye killer actually solve this problem. But if fish eye kiiller would solve it, what am I doing wrong in the first place?
 
#29 ·
71gtx said:
The reason I don't think that it is too heavy of a coat is this: The first light pass I had showed the "fish eyes" and adding more paint never improved them. As far as contamination this is what I did:

I wet sanded a previous water problem, cleaned with soap and water, cleaned heavily with metal prep, and finally went over the surface with a tack cloth.

Could too much hardener cause this? And would fish eye killer actually solve this problem. But if fish eye kiiller would solve it, what am I doing wrong in the first place?
Too much hardner would not cause this. If you get it in the first coat and its bad enough - better off to stop and clean it off or let it dry and wetsand and clean again before painting.

Metal Prep - is that a suface wash or an etch for bare metal (don't recall the product name...)

If its a wash did you let it evaporate or dry it off with a clean dry cloth?

Many, many people make the mistake of letting the cleaner evaporate or doing too large of an area before cleaning - what you have to do is immediately wipe off the material before it dries ~ think Karate Kid "Wax On, Wax Off"

Sometimes the rags or towels you use can leech contaminants onto the surface during the cleaning process as well.

Using soap and water is ok during some phases - but here again if any soap residue dried onto the surface that could compound problems as well.

ONLY use fisheye inhibitor as a last resort - basically you're adding silicon to the paint!

Personally I have only had to use fisheye inhibitor on a very few fiberglass cars where there was an issue.

Also -sometime when you notice light fisheyes in the first coat let it tack up really well and mist coat the next basecoat sometimes you can get it to cover.

But usually its better to stop and fix it because the fisheyes or other imperfections compound with more layers and clear.
 
#30 ·
This is quite apparently a case of surface contamination from improper prep. Did you wipe the surface with a prep solution before spraying? And if so did you follow the instructions to the letter? Did you use CLEAN wiping rags? This is probably the most common cause of paint failure but it is easily remedied by proper cleaning however there is no saving what you have already sprayed, it will have to be removed in order to remove the cause of the problem. Please don't ask how I learned about this :rolleyes:
 
#31 ·
After cleaning with soap and water, The surface was wiped down with Painters Choice Pre-Clean, with blue shop rags (you get in a box of 200 at lowes). immediately after wiping down i wiped the pre-clean off with another clean rag and did not allow it to evaporate. after this was done, a tack cloth was used on the surface. might i add that the surface i am painting is 10 feet in the air and 18 feet long, the only way to paint is to walk on the surface behind my paint stroke. I walked with clean socks, no shoes. The amount of fish eyes would make me think that it has nothing to do with the socks.
 
#33 ·
71gtx said:
After cleaning with soap and water, The surface was wiped down with Painters Choice Pre-Clean, with blue shop rags (you get in a box of 200 at lowes). immediately after wiping down i wiped the pre-clean off with another clean rag and did not allow it to evaporate. after this was done, a tack cloth was used on the surface. might i add that the surface i am painting is 10 feet in the air and 18 feet long, the only way to paint is to walk on the surface behind my paint stroke. I walked with clean socks, no shoes. The amount of fish eyes would make me think that it has nothing to do with the socks.
Sounds like you prepped it right - what is it you are painting that is 10' in the air and 18' long?
 
#34 ·
I had two filters at the gun back to back, the kind with the silicone beads or whatever they are inside.

Im a college student who quit working for Harley Davidson and built a mobile billboard from the ground up, my last step being paint and its going awfully wrong.

I talked to a guy at the paint shop and he recommended just using fish eye killer. What are the negative effects?
 
#35 ·
Sometimes I have seen tack rags that have ended up causing fisheye problems before.

This would be due to the "glue" residue on the tack rag getting transferred to the surface.

I've sometimes CAREFULLY used something more aggressive like lacquer thinner on the trouble spot areas and then re-cleaned with the prep wash - hard to do with fresh paint!

I'd clean the area, scuff the paint and let it sit open a couple of days open to allow the solvents to escape, clean again and put a sealer on it.

Keep the first couple of coats lighter to see if you get a reaction again - make sure you allow the recommended flash time between coats.
 
#38 ·
it is for myself, and the way i built it it is pretty professional. i cannot have imperfections with the amount of time and effort i put into it, understanding that there are ways around it. im going to try some different approaches today and let you guys know what happens.
 
#39 ·
71gtx said:
it is for myself, and the way i built it it is pretty professional. i cannot have imperfections with the amount of time and effort i put into it, understanding that there are ways around it. im going to try some different approaches today and let you guys know what happens.
I understand - I always overkill on quality of my projects too!

I just wanted to point out that someone driving by your billboard at 5mph or 50mph is going to only see the advertisement and not any imperfections :thumbup:
 
#40 ·
Ok, I've tested two more panels and Ive received similar results. I even added some fish eye eliminator to it and it appears similar.

When I am spraying the surface, there are a TON of dimples in the paint when it comes out. Im wondering now, my gun is a Kobalt gravity feed from Lowes. Could this be restricting the paint flow or potentially not be the right gun for enamel based paints?
 
#41 ·
This still sounds like surface contamination :confused: but if the gun is new did you tear and down and clean it before using it? Probably not the problem since you have tried this several times. The shop rags themselves maybe? I ran into that problem sometime back with some paper towels that were clean but something in the towel itself caused the problem. Try some wiping rags made just for painters.
 
#42 ·
71gtx said:
Ok, I've tested two more panels and Ive received similar results. I even added some fish eye eliminator to it and it appears similar.

When I am spraying the surface, there are a TON of dimples in the paint when it comes out. Im wondering now, my gun is a Kobalt gravity feed from Lowes. Could this be restricting the paint flow or potentially not be the right gun for enamel based paints?
Can you get a decent picture of the paint problems?

The gravity feed gun could be a problem - I've seen some guns assembled with too much lube in the packings - it could also have an incorrect tip for spraying stains or something other than an automotive grade paint.

What gun and material did you use to primer the sign with?

Did you spray a sealer first before applying the topcoat?
 
#43 ·
What kind of material is this made of? Is it a steel panel? Was your first coat of primer sprayed onto the panel itself or was the surface already coated with some other type of coating? This is really puzzling since you have apparently taken the time to do this right.
 
#44 ·
I will get pics asap. The surface is 1/8th inch aluminum, sanded very thoroughly and primed with a self-etching sealer. The sealer seemed to go on better but it was a different consistency so its hard to say. The paint shop set me up right for aluminum. I feel like the gun may not be allowing enough paint to flow. I will try a different gun, pick up some diffferent rags, and possibly add a little bit more reducer and see what i get.
 
#45 ·
71gtx said:
I will get pics asap. The surface is 1/8th inch aluminum, sanded very thoroughly and primed with a self-etching sealer. The sealer seemed to go on better but it was a different consistency so its hard to say. The paint shop set me up right for aluminum. I feel like the gun may not be allowing enough paint to flow. I will try a different gun, pick up some diffferent rags, and possibly add a little bit more reducer and see what i get.
Did you use a wash primer or something like DP90?

PPG makes a "wash primer" for aluminum that is a very thin substrate that I would normally use on the clean aluminum and then I would use the correct color coded DP primer before applying the paint.

I just don't recall what the topcoat methods are for the wash primer and if you can apply a topcoat directly over it...which I know you can do with the DP products.
 
#46 ·
well, problem solved guys, my cousin let me use his old enamel gun, a binks 7, and everythings working good now. looks like the lowes gravity feed was made more for base coat clear coat. i appreciate all of your help, take care and best of luck to future projects. :thumbup:
 
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