What caused my paint gun to do this?

[linx310]

I was painting my M1009 this weekend. On Saturday I put down the base coat of Gillespie green and my Harbor Freight HVLP gun was working just fine.

When I was finished I took it apart and cleaned it up. Today I went out and painted the camo on.

About 1/3 of the way through putting down the black it started puking large splotches of paint out.

I was using a ratio of 4 to 1 like the instructions for the paint said to.

I was to close to running out of day light so i stopped painting which sucks because I was hoping to be through with the truck portion of the paint job.

I cleaned the gun and didn't see any thing wrong.

Do you think maybe it became clogged?

 

[67_C-30]

They usually do that when the air vent on the top of the cup gets clogged. I usually keep a small piece of wire (single strand, like a bread tie with the plastic pulled off) stuck in mine, and I'll work it up and down and around several times while painting to make sure it doesn't get clogged. It usually happens from when the gun is tilted to paint the roof or hood, and by as time goes by it dries in the vent and clogs it.

 

[67_C-30]

The truck is looking good though!

 

[rlwm211]

You may have a screen down in the bottom of the port where the paint cup screws in and that can get clogged and when you clean the gun the thinner removes the paint that has accumulated on that screen.

I have a Campbell Hausfield HVLP and I found I could not shoot heavy based paint without removing the screen. This is not a big deal when you are shooing flat or semi flat paint. It is when you are shooting gloss and get a glob, or some piece of junk because the screen did not catch it. That is when you should have that screen installed.

Just me experience in shooting heavy based enamels with that type of gun and it may or may not be applicable.

Best of luck
RL

 

[linx310]

I never thought to check the vent hole on the paint cup. I am betting that is what was wrong.

I ordered some disposable paint cups last night since these things are a pain to clean.

 

[zout]

It is worth the cost to purchase the brush cleaning set for paint guns.

You evidentually have a pot gun - tear it totally apart - brush everything to clean metal and re-assemble -I ususally stick a slight bit of air tool oil on my parts - then before I spray I clear out any debris.

Same for HVLP guns - get the allen wrench set out and totally tear it down to clean it. I have both sets of guns so the brush set is really handy and can handle the cleanign agents.

 

[mistaken1]

Looking good.

 

[flyxpl]

your vent usually will cause a stoppage of paint because of the vacum buildup .

 

[rlwm211]

When the vent plugs, you start with a great pattern and then it fizzles out. Starves for paint. Splattering is when solids and unmixed paint get to the nozzle.
It is possible that the vent being plugged can relive itself suddenly and then you get a lot of pain all at once....well, it could be...I am not sure it is not something else though.

Just my two cents.

RL

 

[RANDYDIRT]

I get the same problem when using a cheap hvlp gun while spraying primer. I think you need a larger tip for some high solid paints. On the other hand I have a Binks pot gun with a 66 nozzle, and I can spray about anything with it.

Dirt