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I'm curious if I can finish wood with an automotive paint gun. I have plenty of dry compressed air and a couple of spray guns. I just wonder if there is a difference between the finishes that would cause problems.

Thank you
 

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where's my table saw?
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Old School
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I'm curious if I can finish wood with an automotive paint gun. I have plenty of dry compressed air and a couple of spray guns. I just wonder if there is a difference between the finishes that would cause problems.

Thank you
No problems. Many of my guns were bought through automotive supply, but don't tell anyone.





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I'm curious if I can finish wood with an automotive paint gun. I have plenty of dry compressed air and a couple of spray guns. I just wonder if there is a difference between the finishes that would cause problems.

Thank you
It depends on the finish. The more the paint is like automotive finishes the better it will work. Some finishes made for wood are much thicker and need a sprayer with a larger orifice. Latex is one finish that doesn't do well with a cup gun. You end up having to thin it so much to get it to spray it's more like colored water and takes too many coats to get the job done.
 

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Around here Binks guns are considered the best in the automotive paint business. They are expensive. They are also excellent furniture spray guns.

George
 

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Uncle Fester
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cabinetman said:
+1. :yes: You got that right. I have a few #7's that are my favorites. .
I'm curious about auto spray guns. Are you using a spray room or booth?
I was having issues with the amount of overspray I was getting . Thoughts?
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Old School
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I'm curious about auto spray guns. Are you using a spray room or booth?
I was having issues with the amount of overspray I was getting . Thoughts?
Thanks
More of a room than a booth. An unoccupied alley for four in wall mount exhaust fans, and a draw drape. Fifteen feet by twenty five feet, not called a spray room, but rather a 'clean room'...in case an inspector stopped in. Behind the drape.
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Uncle Fester
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cabinetman said:
More of a room than a booth. An unoccupied alley for four in wall mount exhaust fans, and a draw drape. Fifteen feet by twenty five feet, not called a spray room, but rather a 'clean room'...in case an inspector stopped in. Behind the drape. . .
Thanks
You have a set up to control overspray
A fine set up at that
 

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I'm curious about auto spray guns. Are you using a spray room or booth?
I was having issues with the amount of overspray I was getting . Thoughts?
Thanks
You're going to have overspray no matter what gun or system you're using. The extent to it depends on what spray equipment is used, where you do it, and what you do to control it. For the hobbyist, it's either in the garage, some room in the house, basement, or outside.

If you spray outside, you have issues with temperatures, wind, rain, bugs, hunidity, and where overspray actually goes. If done inside, just having windows open for ventilation may help, but for the most part there will be an accumulation of overspray.

It also matters what media you use. An oil base spray will linger in the air for a long time, land on everything, and you have a sticky mess. If it's lacquer, it will dry pretty fast, but still gets on things. Waterbase polyurethane dries almost as fast as lacquer, has much less odor, and not as toxic.

Ventilation, or for better terms exhausting overspray has to have a fan or fans exhausting air to the outside, and a filtered air inlet that allows as much air in as what's being exhausted. Done proportionally, the spray area stays clear of overspray. An efficient two cartridge respirator should be used.





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I'm curious if I can finish wood with an automotive paint gun.
You can, and can get acceptable results if the guns are kept very clean - cross contamination is a big issue, particularly when switching between pigmented and clear finishes.

You might be better off with a compressor-driven HVLP gun. Some are available for reasonable prices, such as some of the HF guns. They will waste much less material and have little to no overspray. We use an HVLP trim gun to finish rails and styles before assembly, so we don't have to mask the tenons to keep them clean.
 

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Discussion Starter #13
woodturner9 said:
You might be better off with a compressor-driven HVLP gun. Some are available for reasonable prices, such as some of the HF guns. They will waste much less material and have little to no overspray. We use an HVLP trim gun to finish rails and styles before assembly, so we don't have to mask the tenons to keep them clean.
This sounds like a good option. Thank you all once again.
 

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There has been quite an improvement in guns in the past years.

I use a medium priced Devilbiss Finishline gun, HVLP with disposable gravity cups. With nozzles from 1.3 up to 2.2 it is multi purpose, from furniture, auto, to latex. It puts the finish exactly where you want it from 1/2" wide to 8" wide depending how you adjust, with almost zero overspray. With the disposable cups, clean-up is faster than cleaning a paint brush. I spray fast drying finishes in my shop, WB or Solvent, two exhaust fans, a mask and open windows. The little bit of overspray turns to dust about 3' away from the gun tip, it can be vacuumed away when cleaning up. Full open it needs 13CFM, but with furniture settings it is probably closer to around 4cfm.

The only disadvantage is I have to clean my shop and de-dust before each spraying session. With good weather I spray outside.
 

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cabinetman said:
HVLP guns have a higher CFM demand than siphon guns. Your compressor may not be adequate. For a small area, you will still get an accumulation of overspray with an HVLP setup, albeit less than a conventional spray system. What do you have available for a spray area, and compressor? .
I don't remember the CFM output, but it's a 5 hp/80 gallon rollaire, so I'm sure I have enough volume. My barn is 25 X 40, but I don't yet have an area for finishing. I want to set up a track and curtain, like you might see in a hospital.
 

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I don't remember the CFM output, but it's a 5 hp/80 gallon rollaire, so I'm sure I have enough volume. My barn is 25 X 40, but I don't yet have an area for finishing. I want to set up a track and curtain, like you might see in a hospital.
That's what I did...see post #9.





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This sounds like a good option. Thank you all once again.
FWIW, I've used the HF 47016 with good results, cost is under $20.

When comparing air volume required for different spray guns, pay attention to the pressure as well as the volume. HVLP spray gun specifications are typically cited at lower pressure - for example, for the 47016, the spec is 6 cfm @ 40 psi. Compressors and other tools are normally spec'ed at 90 psi. As a result, it may seem like the HVLP gun requires more air, but it really doesn't - the spec is about 2.6 cfm @ 90 psi. In other words, the air requirement is so low it will work with nearly any air compressor.

Even if you want to use a conventional spray gun, which typically requires more air volume (e.g. 6 cfm @ 90 psi), you don't necessarily have to have a huge compressor. The normal 20 gallon 6.3 cfm at 90 psi shop compressors will work, but you may have to pause periodically to let the tank recharge. Spray until you notice a pressure drop, let the tank recharge, then spray some more. Depending on the size of compressor and tank, it may be a little tedious, but it will work.
 

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We have a Campbell hausfield and we spray in a large room mostly stain lacquer and lacquer based paint. But we have little ventilation and no masks. The down side of a crappy boss. But the gun works great it is gravity feed
 
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