Paint solution (for me anyway)

I have been fighting with the roughness of my application of various paints and clears (even primers) and I think I have found the culprit. I was setting my air pressure (at the wall) at about 45, thinking that has to be enough. Yesterday I checked the pressure at the gun (HVLP) inlet (with the nozzle open) and wasn't getting the 40 or so lbs that I think I need there to get the 10 or so lbs at the nozzle.
I opened up the regulator at the wall and it took almost 60 lbs there to get 40 at the gun and wala, smoother coverage with my paint. If you are having orange peel problems, that seems to me to be the cheapest easiest first thing to check.
I know there are many threads on this subject, but just my experience.
Jim

 

I struggled with that for some time being self-taught. After blocking a lumpy paint job down more than one time, I hearned real quick.

 

That's good information, thanks for p***ing it along. Oh and for the record, it's " viola" not "wala"

 

had a simular situation, i used to regulate the pressure with a valve at the end of the hose. could never get perfect flow, got rid of the valve, installed one on the wall.

 

They make a regulator that goes at the gun they are pretty cheap.

 

Very true I always have a small regulator and disposal ball type air filter right where it goes into the gun

 

that's what i mentioned. with hvlp it restricts the volumn.

 

Got one on the wall and at the gun. Painted some black tonight. Startet out with relatively low pressure and raised it a few times during the job. Kept getting smoother as I went along.
j

 

Yup for every 20' of hose you get 5 lbs. of pressure drop. Then every coupling will drop the hose pressure. So you need the pressure at the gun to set things up. I guess I did learn something in our Level 1 apprenticeship program. Level 2 and 3 where even better.

The Old Tinbasher

 

Hvlp needs volume, run the largest diameter air hose you can find. Also check your fittings. Alot of the quick disconnnect fittings are a smaller diameter inside than the hose size they attach to. Low restriction fittings are available and can make a big difference.

 

Glad to know things are working out- can't wait to see the end product Jim!

 

One of the hardest things to get over for me was inlet pressure vs air cap pressure with an HVLP. For my Sata, I need to have 29 psi inlet to get 10 psi at the air cap. That's phenomenal drop. At lesser pressures, the gun "seems" to be spraying well...until I get it dialed in! The little digital air gauge on the gun is a great tool if I remember to buy batteries before I'm ready to spray.

A side note on those inline filters - change them frequently. I was spraying at my father's garage (car in my avatar). I didn't realize he was having to add oil to his compressor relatively frequently due to blow by. I was making the first coat of clear...worked the p***enger's side, went down the driver's side, back to the p***enger's side - suddenly craters all over the place. The oil saturated the inline filter and started blowing through the gun. Made a big job much bigger in an instant. Just remember the more filtration the better!!

 

I like a 2qt pressure pot with a Develbis hvlp, I have a regulator on the pot and one behind the dryer on the wall. What I like about this setup is you can spray anything on any angle while you hold the pot in the other hand.