# Shellac -- Cleaning the HVLP gun



## d38 (Sep 6, 2017)

What do the members here who HVLP spray shellac use to clean the gun, and how easy is it?

I've sprayed about a gallon of Target Coatings water-based topcoat over the last 6 months, and of course, it just disappears in water making cleanup extremely easy-no brushing of small holes required, just soak, splash, rinse. 
But I don't want to get my gun gunked up with the shellac and cause troubles spraying the water-based topcoat.

Does the shellac dissolve and clean up with DNA as well as water-based finishes do with water? If there's potential to have some shellac get stuck in the ports/nozzle, I might simply buy a second gun like this:
https://www.paintsprayersplus.com/AeroJet-RS1-HVLP-Turbine-Spray-Gun-Non-Bleed-Type-p/ajt-rs1.htm

My current project is three oak kitchen cabinets-one base and two tops. I want to oil-based stain, then Bullseye Sealcoat to help bring the grain out more, then water-based top coat.

Any feedback would be appreciated.


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## pintodeluxe (Sep 12, 2010)

Just disassemble the gun and soak it in DNA for about 10 minutes. Wipe it down and put it back together. You can reuse the denatured alcohol for several cleanings if you store it in an airtight container.

I find lacquer is the easiest finish to clean off a gun, but shellac isn't far behind.


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## LesB (Dec 21, 2008)

Shellac breaks down with house hold ammonia. That is what I use to clean my brushes when I brush shellac. Dilute it about 50+%. That is one reason you don't want to use a shellac finshs where cleaning compounds contain ammonia might be used…..ie. Window cleaning agents usually have ammonia.
That is a lot cheaper than DNA.


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## mel52 (Sep 4, 2017)

I clean everything in DNA and make sure I spray some through the gun before drying everything. I have a problem with the ammonia ( physically ),so I don't use it.


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## wapakfred (Jul 29, 2011)

It's what LessB said…use household ammonia (unless you have a problem with it). Here's why: DNA will dilute the shellac, no matter what you do you won't get all of it out…thought the remaining trace amounts may not harm anything. It's also considerably more expensive, though you could save it and re mix with shellac down the road. Ammonia, on the other hand, absolutely destroys the shellac getting you gun squeaky clean. There is a down side, ammonia can stain/discolor aluminum (at least it did on my gun). It's not harmful, but may give you an appearance you don't like. I usually mix the ammonia with warm water in a 5 gallon bucket and soak the gun in it for several minutes.


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## DustyM (May 16, 2016)

> Shellac breaks down with house hold ammonia. That is what I use to clean my brushes when I brush shellac. Dilute it about 50+%. That is one reason you don t want to use a shellac finshs where cleaning compounds contain ammonia might be used…..ie. Window cleaning agents usually have ammonia.
> That is a lot cheaper than DNA.
> 
> - LesB


This is amazing advice. I've been using DNA, and it is pretty darn pricey. Thanks for posting a more cost-effective alternative!


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## mel52 (Sep 4, 2017)

Fred Hargis, what dilution rate do you use with the 5 gallon bucket set-up. Ammonia only bothers me in stronger solutions. I may try it to see if I have any problems. I do know that a 50/50 solution affects me a little. Thanks. Mel


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## wapakfred (Jul 29, 2011)

I don't actually measure it, just pour some in…but it has to be only a cup or so I add to the water. The bucket isn't completely filled…maybe 3-3 1/2 gallons of water. If the solution is too weak it will still work, just take a little longer.


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## rwe2156 (May 7, 2014)

Huh.. I've always just ran some DNA through the gun followed by air followed by some more DNA.

Although I do think it will adequately clean the gun & never had an issue, sometimes I'm cleaning the gun our 3-4 times a day. I think I'll start using ammonia nothing else will save some money.


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## pintodeluxe (Sep 12, 2010)

The smell of ammonia alone would keep me from using it. It only takes 2-3oz. of DNA sprayed through a gun to clean it. A small reservoir of DNA can be reused to dunk the parts, so long as it's stored in a sealed container. I can clean my gun 15-20 times with a half gallon of DNA.

To me it makes most sense to use the appropriate thinner for the product you're using. Read those safety data sheets with any mixing you do… many of us woodworkers are good finishers, but few are good chemists.


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## d38 (Sep 6, 2017)

Thanks everyone. 
As long as I can handle the fumes, I'll use diluted ammonia (with my 3M respirator). Don't want any residue left behind that could affect subsequent uses of water-based top coats.


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## tdwilli1 (Jan 21, 2014)

> What do the members here who HVLP spray shellac use to clean the gun, and how easy is it?
> 
> I ve sprayed about a gallon of Target Coatings water-based topcoat over the last 6 months, and of course, it just disappears in water making cleanup extremely easy-no brushing of small holes required, just soak, splash, rinse.
> But I don t want to get my gun gunked up with the shellac and cause troubles spraying the water-based topcoat.
> ...


Since you use Target Coatings have you tried their WB Shellac? I'm going to test it out on a small project next.


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## d38 (Sep 6, 2017)

I used 50/50 water, ammonia, and as everyone mentioned, it cleaned up great. I kept my 3M mask on while doing this too. 
The Bullseye Sealcoat sprayed pretty well. I'm applying it to inexpensive unfinished cabinets that have been stained with oil-based Minwax. The veneer on the door panels is super thin, and the open grain portion seemed to just soak up the Sealcoat and left a rough surface. So I sprayed a second coat and put it on fairly heavy.
I waited a day, and sprayed General Finish Enduro Sanding Sealer (yea, I realize Sealcoat is a sealer, but I only have one quart of General Finish 450 that will give me one coat, so I used the sanding sealer as another coat).

The Sanding Sealer crazed/crackled for some reason. I called Rustoleum, and they didn't understand why. I'll call General Finish Wednesday. Its not real bad, so worst case, a good buffing with a burgundy scotchbrite pad, and spray the 450.


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## OSU55 (Dec 14, 2012)

Its possible the heavy coat of sealcoat you put on crazed. I have experienced it myself. Sand it or better yet you can do a "rough "french polish" with a pad and dna - it will move the shellac to fill in the cracking.


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