hvlp spray gun cleanup - am I excessive in cleaning?

[Jesse Tutterrow]

I am new to hvlp spray finishing. In fact this is my second project using my Earlex 5000 spray equipment.

I have noticed in both projects (spraying lacquer and now spraying oil based paint) that I am using over a half gallon of cleaner (lacquer thiner, mineral spirits). So, here is what I am doing, please tell me if I need to change something.

1. Drain as much finish as possible from the cup. About 30 seconds of holding it upside down.
2. Fill the cup about half full of solvent and swish it around. I put a plastic lid on the top and hold it tight and swish to cover the top half of the cup. I drain this out and throw it away.
3. Fill the cup about half full of solvent and put the gun on and spray it out of the gun till the cup is empty. I drain and throw this away.
4. Dissassemble the gun and put the parts (needle, nozzel, spring, adjustment knob, spray fan assembly into a container and add solvent till everything is submerged. I will save this solvent and use it in step 2 the next time.
5. While #4 is soaking I use clean solvent to wipe down the outside of the cup, gun and hose. I dispose of rags.
6. Take #4 and remove each part, swish it in solvent and blow it down with air from the hvlp unit.
7. Reassemble the gun
8. put about a half cup of solvent in the gun and spray it dry.
9 Dissamble the gun and inspect each part to see if I can see any finish material. If so I go back to step 4.
10. After everything is clean, I set each part aside to dry.

Today, I sprayed about 2/3 quart of oil based paint and used over a 1/2 gallon of mineral spirits. By time I finish this project I will have used about 2 quarts of paint and over 2 gallons of mineral spirits. It just seems like I am using too much solvent, but I can't figure out what to do differently.

Any Suggestions?

[Larry Fox]

I personally think you are using too much solvent. I would make the following modifications:

Step
1) When done, I would wipe the cup out with a solvent-soaked paper towel or rag to get most of it out.
2) I would just put about 1/2" of solvent in the cup and do the shake and toss. Recall - most of the finish got wiped out in step 1
3) Just put about 1" in the cup and do this. I typically hold my hand tightly over the nozzle and spray the solvent through for a sec then blow the rest through
4) No need to submerge. Get yourself a cleaning kit and clean the parts as you take them out. Uses < 1/4 cup of solvent for the entire gun.
5) Use the solvent which is leftover from 4 to do this.
6) unnecessary
7) ditto
8) you only need about 1/2" of solvent for this
9) Unnecessary
10) Unnecessary - the gun will dry fine

I give it a good cleaning between sessions and every once in a while I break it down completely for a thorough cleaning. My gun has sprayed many gallons of finish and still looks and sprays as good as the day it was new (better in fact). I have a PP-based system so I have to deal with the lines and the pot but I followed the above when I used a syphon gun.

Hope it helps.

[John TenEyck]

If you spray waterbased products your solvent costs are zero. There are so many good waterbased products these days, there's not much reason to keep using solvent based ones.

[Chris Fournier]

Yes you are wasting a lot of solvent. Swish requires a couple ounces, and I save the swish for the next swish depending on the materials used or I add it to the material sprayed which requires thinning often times. I run clean solvent through the gun with the air screw shut off! You get a tidy stream of solvent which you can collect and use again. A cleaning kit is important but I rarely ned to really overhaul the gun. I cut my solvent use in half when I asked myself the same question that you have in this thread. Good luck.

[Sam Hamory]

I agree with John, water based products are so abundant I haven't used solvent base for twenty years, professionally. But otherwise Larry has a more efficient cleaning system that usually works fine. I have the 5000 also and I don't baby it. I use it to make money, the outside of my gun doesn't have to be clean, the inside does.

[Curt Harms]

If you spray waterbased products your solvent costs are zero. There are so many good waterbased products these days, there's not much reason to keep using solvent based ones.

Winner. And I know from experience that acrylic enamel thinned with a splash of water will spray just fine. I don't know how it's going to hold up- it's only been a couple seasons- but so far it looks like the day it was put up.

[John TenEyck]

Winner. And I know from experience that acrylic enamel thinned with a splash of water will spray just fine. I don't know how it's going to hold up- it's only been a couple seasons- but so far it looks like the day it was put up.

Same here. I've sprayed waterbased poly and acrylic enamel through guns not designed for waterbased products and, so far, three years later they look and work just fine. I just make sure to clean them out with soapy water when I'm done and then spray an ounce or so of alcohol through them to remove any residual water. I think I regreased the needle bushing once, just because, but it looked fine. But even if they only last a few years, I paid so little for them that it won't hurt too bad to replace them. I've gotten my money back many times over already.

[Jesse Tutterrow]

Thanks for your imput. I have made changes to how I clean my gun.