Whether to Spray Paint with an Air-Assisted Airless Gun
Cleaning an AAA after spraying oil-based paint through it can be a chore. September 29, 2014
Question
Is anyone using a Kremlin pump (blue one) to shoot oil base primer? I would like to not have to thin - I tried on my last job but the biggest tip I have is a 9 and it was a chore. Can I use a larger tip or just use thinner? Some pieces will have to be sprayed vertical so I’m trying to keep the hang by not thinning.
Forum Responses
(Finishing Forum)
From contributor H:
It can spray it but I would take a lot of time cleaning the unit after you use it with an oil base product. You can go to a 12 tip and if you are concerning about runs, get a wider tip like a 12-14 which will spread the coating over a wider area. I would think that a spray pressure of about 700-900 psi or 70ps on the right regulator would work just fine.
From contributor J:
Don't do it, unless you have dedicated lines for alkyd/oil house paints. Cleaning the hose lines would need at least two to three gallons of spirits, plus time and effort. If you have a simple Graco or Titan airless sprayer that is the best solution.
From the original questioner:
Now I am confused a bit. We have used oil based through here before but just don't have the right tip I believe. I flushed with regular paint thinner, followed that with lacquer thinner, maybe a quart each time and have sprayed 10-15 gallons of clearcoat since then with no issues.
From Contributor J:
A 10:1 pump should be fine as mentioned. The 12 tip is what you need. I agree when flushed out properly as it appears that you are you should be able to jump from oil to solvent. I like to pull the screen at the gun base also.
From contributor U:
I made the mistake once of spraying oil based poly in my AAA pump. I cleaned with spirits followed by acetone. Thought I was never going to get all of the oil out of the lines no matter how much acetone I ran through it. It fisheyed everything afterwards. I wound up replacing the fluid line and still had a fisheye or two now and then for weeks. If you have a designated pump or cup gun/gravity gun I would recommend going that route.
