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The Man
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Discussion Starter · #1 ·
I have just purchased my first HVLP spray gun. It was a cheap-o one I got off Amazon because if I screw it up learning how to use it I didn't want to be out more than $40. So to start I'm only going to spray water based dye and thinned shellac (1/2-1lb.)

The big thing I'm wondering about is how to clean it properly (like what products I should use) afterwards.

Thanks for any help
Bobby
 

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The dye can be cleaned out with soap and water, I use a dish soap like Dawn but I'm guessing about any liquid detergent will work. Shellac can be easily cleaned with a few different things, like alcohol and other solvents. But the cheapest (and maybe easiest) way to clean it out of a spray gun is the soak the gun in a 5 gallon bucket filled with warm water and household ammonia. The ammonia destroys the shellac, and it's really easy to rinse it out after the ammonia has done it's job. If your gun has a regulator or pressure gauge on it remove those or don't let them soak in the solution in some fashion. It helps to have one of those little gun cleaning kits that has small brushes and such to scrub out the tiny orifices, at the very least have some pipe cleaners to do that.
 

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Old School
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I have just purchased my first HVLP spray gun. It was a cheap-o one I got off Amazon because if I screw it up learning how to use it I didn't want to be out more than $40. So to start I'm only going to spray water based dye and thinned shellac (1/2-1lb.)

The big thing I'm wondering about is how to clean it properly (like what products I should use) afterwards.

Thanks for any help
Bobby
For waterbased products, I use water. For oil base products I use either mineral spirits or naptha. For lacquer based products, I use lacquer thinner. If the gun gets gummed up, lacquer thinner (or acetone) will dissolve most any finish.

If you'll be using it for different medias, right before you use it clean it out, and run the appropriate cleaner through the gun.






.
 

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I have just purchased my first HVLP spray gun. It was a cheap-o one I got off Amazon because if I screw it up learning how to use it I didn't want to be out more than $40. So to start I'm only going to spray water based dye and thinned shellac (1/2-1lb.)

The big thing I'm wondering about is how to clean it properly (like what products I should use) afterwards.

Thanks for any help
Bobby
You get china quality with china tools... :yes:

My 'garbage' spray guns get field stripped and placed in a can of lacquer thinner after use. I run thinner through them again after reassembly and before use...

Guns not suitable for 'finish' work in my opinion...

I would NOT buy ANY spray gun that I could not also buy 'parts' for... :no:

No need buying a new gun if you just 'need' one part. (unless it came from china and you cant get parts)
 

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I normally start cleaning a gun with the solvent made for the paint that was in it last and then flush some lacquer thinner through it last. In you case that would be water for the water based stain and alcohol for the shellac. Sometimes espeicially with water based finishes some water will stay in the gun and if you use it for shellac some water will get in the finish. Flushing it with lacquer thinner doubles as a dryer as what is left will evaporate. I don't see anything wrong with cheap guns for wood finishes. I use only Harbor Freight sprayers, mostly #97855
 

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The Man
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Discussion Starter · #7 ·
Oneal I'm not using it for finishing. It is for a dye base coat to tent my finished work, a quick and easy barrier coat of shellac, etc. I am using it to practice spraying a medium. When you're learning to ride a bike you don't buy a $2,000 Specialized unless you're a fool.

Thanks to you all for the responses! I have a cleaning kit and will be getting with it shortly!
 

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Oneal I'm not using it for finishing. It is for a dye base coat to tent my finished work, a quick and easy barrier coat of shellac, etc. I am using it to practice spraying a medium. When you're learning to ride a bike you don't buy a $2,000 Specialized unless you're a fool.

Thanks to you all for the responses! I have a cleaning kit and will be getting with it shortly!


I use crap guns for that sort of stuff as well.

:smile:

Dont 'need' quaility tools for that sort of work.
 

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I have expensive guns and cheap China ones. When you get a little practice, you can get a good a finish with any gun. It's about who is pulling the trigger.


.



Nope...

You can't get the same results with 'china' tools. :no:

Post pictures of your 'flawless' finishes done with 'china' tools. :smile:


(you won't)
 

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Rick Mosher
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You can get a great finish spraying with a Preval sprayer so that isn't what your money is buying. I have used just about every type of gun at every quality level there is and here is what I have found out.

The cheaper guns almost always have some kind of crappy "O" rings that keep them from leaking and always seem to swell up making the gun useless, this usually happens during the cleaning process especially if you are soaking the gun.

Just running solvent through a gun doesn't clean it properly. Even gun cleaning machines that pump solvent through the fluid passages don't do a decent enough job. I have used them and then taken the gun apart, I always find some residue inside the fluid tip and fluid passages which will build up and potentially ruin your gun.

I own a Sata gravity gun which I got from an automotive painter friend for $100, It is an older NR95 model which still works great. The difference in this gun is that all metal parts are machined and there are NO O" rings to go bad. (A new Sata can run over $800 so they are not for everyone)

I would buy a gun from a reputable supplier (Binks, DeVilbiss, Sata, Iwata etc) and then if required get all replacement "O" rings and gaskets needed so they can be replaced.

Become familiar with the exploded diagram of your gun and dis-assemble all fluid related parts after each use and clean in required solvent, after using water, a flush with acetone is a really good idea to keep any aluminum from pitting. NEVER soak a gun completely in solvent of any kind! The air passages are not intended to have fluids inside them and can cause scaling where it can't be cleaned out resulting in chunks of grit coming out in your spray pattern.

The proper way to dis-assemble a spray gun is to first remove the fluid needle, this is very important or you can get leaks from the lapped fit with the fluid nozzle. After removing the fluid needle take off the air cap and then use the proper wrench to remove the fluid tip. (Don't be tempted to use your vice grips or pliers!) Remove any teflon or rubber packings or O rings and make sure you don't soak them in solvent. Using a proper gun cleaning kit, thoroughly clean all fluid areas of the gun and soak the fluid needle, fluid tip and air cap in clean solvent. Check inside the fluid nozzle and make sure no paint is still inside, the small bottle brush in your gun cleaning kit is excellent for this.

Re-assemble your spray gun making sure to replace the fluid tip and properly tighten it before replacing the fluid needle assembly. Now the next time you need it your gun will work perfectly just like it did when it was new.
 
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