Paint gun adjusting.

That Sata guy on one hand talks about putting 100 psi directly into the gun and using the gun valve to pinch it down, correct NG.
He skipped over having a regulator at the gun! That paint gun air valve should be wide open, with a good diaphragm regulator at the gun you don't need to mess with that air valve on the gun.
 
best rig is a fresh air hood with a belt . reg on the belt . short hose to your gun. now my hood uses shop air . i don't paint much so the compressor air is fine. good charcoal filter in line works good. great for changing air pressure without going back to the wall or hanging under your gun in the way.
 
I'm still trying to wrap my head around the air pressure thing. I am guilty of doing what that video stated. It has worked for me for years.. I started doing it to ditch the regulator so the gun would be more compact when painting low slung stuff doing collision. I plan on trying the way Barry recommends.

What I don't get is what is the difference between adjusting it at the wall so that the gun is atomizing nicely and adjusting it at the gun with 150 psi going to the gun regulator? PSI is PSI right? And pressure drop is pressure drop? So if I adjust at the wall and it is atomizing nicely at the gun what difference will there be in adjusting it at the gun regulator? The gun itself sees the same pressure in both situation, what is the difference?

With my digital Sata, I will adjust at the wall and the gun will have 30 psi at the gun (using 30 psi as an example) If you adjust at the wall to account for the pressure drop of the hose and have 30 psi going into the gun (no regulator at the gun) or adjust at the gun with 150 psi at the gun regulator the adjust it to 30 psi what is the difference? PSI is PSI right? What am I missing? COuld someone explain what the difference would be? It can't be more volume because pressure and volume are inverse of each other. Would like to know what the quantifiable difference is.
 
Chris I've done it both ways as you described and don't have an answer for you. I put a gauge only at the gun and regulated at the wall. Mostly I use about 85psi at the wall regulator and regulate at the gun down from there. Both worked for me. My compressor cycles from 100 to 150 so I have to stay below the 100, at the wall, to avoid fluctuation. Never was 100% clear to me either. I always keep the air in valve on the gun wide open.
 
Chris_Hamilton said:
I'm still trying to wrap my head around the air pressure thing. I am guilty of doing what that video stated. It has worked for me for years.. I started doing it to ditch the regulator so the gun would be more compact when painting low slung stuff doing collision. I plan on trying the way Barry recommends.

What I don't get is what is the difference between adjusting it at the wall so that the gun is atomizing nicely and adjusting it at the gun with 150 psi going to the gun regulator? PSI is PSI right? And pressure drop is pressure drop? So if I adjust at the wall and it is atomizing nicely at the gun what difference will there be in adjusting it at the gun regulator? The gun itself sees the same pressure in both situation, what is the difference?

With my digital Sata, I will adjust at the wall and the gun will have 30 psi at the gun (using 30 psi as an example) If you adjust at the wall to account for the pressure drop of the hose and have 30 psi going into the gun (no regulator at the gun) or adjust at the gun with 150 psi at the gun regulator the adjust it to 30 psi what is the difference? PSI is PSI right? What am I missing? COuld someone explain what the difference would be? It can't be more volume because pressure and volume are inverse of each other. Would like to know what the quantifiable difference is.
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I’ve navel gazed on this quite a bit over the years. The only thing I could come up with is that the wide open at the wall doesn’t work well when the gun has a cheater valve instead of a true regulator. Given that cheater valves are often sold as regulators it may happen frequently and might be why wall regulation without a gun regulator is recommended by some folks.

Don
 
Chris_Hamilton said:
I'm still trying to wrap my head around the air pressure thing. I am guilty of doing what that video stated. It has worked for me for years.. I started doing it to ditch the regulator so the gun would be more compact when painting low slung stuff doing collision. I plan on trying the way Barry recommends.

What I don't get is what is the difference between adjusting it at the wall so that the gun is atomizing nicely and adjusting it at the gun with 150 psi going to the gun regulator? PSI is PSI right? And pressure drop is pressure drop? So if I adjust at the wall and it is atomizing nicely at the gun what difference will there be in adjusting it at the gun regulator? The gun itself sees the same pressure in both situation, what is the difference?

With my digital Sata, I will adjust at the wall and the gun will have 30 psi at the gun (using 30 psi as an example) If you adjust at the wall to account for the pressure drop of the hose and have 30 psi going into the gun (no regulator at the gun) or adjust at the gun with 150 psi at the gun regulator the adjust it to 30 psi what is the difference? PSI is PSI right? What am I missing? COuld someone explain what the difference would be? It can't be more volume because pressure and volume are inverse of each other. Would like to know what the quantifiable difference is.
Click to expand...

I agree with the PSI being the PSI regardless of whether it was set with a regulator on the gun or the regulator on the wall. The key is to be sure the air valve on the gun is wide open and that the PSI is measured at the gun. I have a pressure gauge that I temporarily install on the gun to set the PSI using the regulator on the wall, which has over 150 PSI feeding it.

So far this method has worked great for me.
 
Okay so maybe @Barry or others can answer my question a little easier, I'll condense what I asked above. If when using my digital Sata and adjusting from the wall I have say 30 psi showing at the gun, how is that different than adjusting the wall regulator to 150. then adjusting with a regulator at the gun to 30 psi?
Genuinely would like to understand this.
 
Well...I'm very interested in this discussion. This is my DV1 with my Iwata regulator FULLY open and adjusting the WALL regulator to get the 22 psi I like for my Devilbiss with a 35 foot hose. I have the trigger fully open.
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Mustang408 said:
Well...I'm very interested in this discussion. This is my DV1 with my Iwata regulator FULLY open and adjusting the WALL regulator to get the 22 psi I like for my Devilbiss with a 35 foot hose. I have the trigger fully open.
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That's interesting. Aside from possible deviations in the three gauges you are dropping about 10psi to the Iwata through the 35' hose, which is about normal. But there is a another 10 psi or so drop from the Iwata to the digital gauge on the top of the gun! So does that mean if you didn't have the Iwata (because you mentioned it was wide open) you would need 50psi at the wall to get the 22 on the top? What is that digital gauge tapped into on the gun?
 
metalman said:
That's interesting. Aside from possible deviations in the three gauges you are dropping about 10psi to the Iwata through the 35' hose, which is about normal. But there is a another 10 psi or so drop from the Iwata to the digital gauge on the top of the gun! So does that mean if you didn't have the Iwata (because you mentioned it was wide open) you would need 50psi at the wall to get the 22 on the top? What is that digital gauge tapped into on the gun?
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On my Pro-Lite, with a 1.4 needle, I need 50psi at the wall to get around 32 at the gun. And, 40psi with a 1.3 tip.

I called Devilbiss and they said to adjust at the wall. Granted, the "expert" sounded stoned.
 
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metalman said:
That's interesting. Aside from possible deviations in the three gauges you are dropping about 10psi to the Iwata through the 35' hose, which is about normal. But there is a another 10 psi or so drop from the Iwata to the digital gauge on the top of the gun! So does that mean if you didn't have the Iwata (because you mentioned it was wide open) you would need 50psi at the wall to get the 22 on the top? What is that digital gauge tapped into on the gun?
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Yea I have dv1s as well and its normal to have atleast a 7 -10psi drop from inlet to the gauge on the gun. I ditched the regulator at the gun on mine and just go off the guns guage while keeping in mind that pressure drop. So I usually shoot bases around 16psi on the gun guage and around 20-22 at the gun gauge on my clear gun
 
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It's Volume attained from Pressure.
Like Natural Gas Service systems.
They were originally Low psig as in Ounces or Inchs of Water Column requiring Large I.D piping in order to supply demand. The whole "if this leaks out from a busted pipe" scenario. Safe but continually had Water contamination into the System.
Now you have High psig and smaller I.D. piping with Regulators to attain the Same required demand. The whole "more efficient transmission and you better call before Digging" scenario.

If you've ever had a hose 'disconect' with 100# blowing out from a stuck coupler. It's not pretty.
I'll stay on the Low side myself thank you.
 
I am going to try the wall adjustment later today on my dv1. I don't use a regulator on those guns as it has a gage on it. I am going to run the gun itself wide open and adjust at the wall for the correct pressure I am looking for. Just to see how it sounds, if that makes sense.

I am so tired of over thinking this shit, but this one has be curious.
 
The one thing I like about the idea of adjusting at the wall is that I am currently running the regulator wide open at say 120-125psi, my compressor itself needs to be cranked up to keep a pressure above that and I don't really like doing that.

If the compressor falls below 125psi and your wall adjustment is 125psi, then no matter what regulator you have on your gun your air pressure is going to change. I had an issue with that and the gauge on my compressor was off. But it seems like every gauge is off, lol.

So I'd rather just run my compressor in the 150psi range, adjust it down at the wall to say 50-60 to get the correct gun pressure needed and then I know for sure ill never run into that issue with the fluctuating air pressure unless of course I forget to turn it on, and even that's not out of the realm of possibilities!
 
You achieve the same result.
The whole idea for hvlp was to atomize the product with Less VOC's produced by the 'process'.
Atomization, either do it with Pressure or Volume.
I understand from doing hvac and air flow dynamics.
You need "X" amount of Air flow to condition a room.
You achieve this with Cubic Feet per Minute,Volume or Feet Per Minute, Velocity.
Enough high pressure FPM thru a single 6×12 grill will work but be so noisy,blow your papers off the desk and be really irritating in your Confrence Room.
Enough low pressure CFM thru several 6x12 grills is almost unnoticed.
Same result,different approach.
With air tools you need the Psig and the Volume in order for them to function properly.
Hvlp Paint guns you just need consistent Volume. Not psig.
Why the need for larger supply from the Regulator to the Gun. You have the length of hose acting as storage and not just squirting right thru the Regulator into it. Which is then 'Regulated' by the gun internally upon exiting the tip.
So a lot of Air displacement and disruption. I prefer the less of,the better.
You either use Psig or Volume.
Hundred ways to do this and the 'best' way is what works for You to achieve Greatness. :cool:
 
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