You can do that as well. It's all a balancing act between distance, paint volume, air pressure, paint thickness, and air temperature.
You can do that as well. It's all a balancing act between distance, paint volume, air pressure, paint thickness, and air temperature.
Thanks guys - it's good to hear that I should be OK in this weather.
I'm using a Star mini gun with a 0.8mm tip. I try to keep the pressure around 20psi, which normally gives me quite a good spray pattern. I think in this case my lacquer's too viscous, as I have the liquid screw backed so far off it's nearly falling out of the gun, and I'm still struggling to get the lacquer on wet, even with the gun held close to the "target".
I think I'll try giving the gun a thorough clean, and then thinning my lacquer more, and see how I go.
I use 0.8mm, so that's not the issue. Either paint viscosity or a gunked-up gun. Do you clean the gun out after every day's use (as well as if you change paint colours)? I run thinners through, then remove the needle and clean that. Also the rotating front nozzle plate and dip that in thinners for a bit to get all the holes clean, and dip the end of the nozzle in thinners as well and wipe that with a cloth.
I think "Cleanliness is next to Godliness" when it comes to spray guns.
I'm quite fastidious with my cleaning. I've paid the price 2 times when taking shortcuts and won't do it again.
I have got a pretty good system down now that allows me to do a very thorough job, and only use about 300ml of thinners.
Disposal of too much old thinner is difficult in a suburban back yard, so I try and minimise as much as possible.
I believe I have the same Star .8mm gun as you Jon. What thinning ratio are you using?
For acrylic lacquer, I do a 50/50 mix and run my nozzle pressure at about 18 PSI. My fluid flow is typically 1/2 a turn in (decreased) and air flow control open full. Unfortunately it's not always a one-size-fits-all thing with the settings, but that's where I start.
Making the world a better place; one guitar at a time...
I’ve been thinning 50/50 so far, and that largely seems to have been OK. I cleaned out my gun again yesterday, but it looked pretty good - just a little lacquer around the base of the needle. I also tried thinning at 5:3, which did give better flow.
I think the real problem is my dunny tent. I think what’s happening is that the lacquer’s going on nice and wet, but I end up with a cloud of overspray that has nowhere to go, so eventually settles on the guitar leaving the powder effect.
I’m spraying at about 20psi. I struggle to maintain a steady pressure anywhere below that. Not sure if that’s my reg or my having a small compressor.
Sounds like the reg to me. The spring in it doesn't have enough range to control to a pressure below 20psi.
But you can use the airflow screw to reduce the pressure down on the gun itself, even if you can’t read what that pressure is. You have to go by the results.
Ah yes, I hadn't thought about that. I might well try that next time. Right now, I think I have enough coats of clear on, so I'm going to leave it for a while. I still manage to get all sorts of things caught up in the wet paint, but I'm hopeful that will sand out OK.
Also, you can put two regulators in series. I have a moisture trap + regulator in the middle of my airline. So with that arrangement you can set the pressure on the compressor regulator down to say 30psi, which means that the second regulator should have less work to do in controlling to a bit less than 20psi.
That's good idea Simon. I hadn't though about that approach. In part because I didn't think about the regulator placement on Jon's rig.Originally Posted by Simon Barden
I also use two reg's but I have my second one (including inline water trap) just before the gun. I run the regulator that's on the compressor wide open and rely on the second one to set my nozzle pressure.
Making the world a better place; one guitar at a time...
I have the same setup. Next time I get the gun out, I'm going to experiment with setting the reg on the compressor. I don't even know how to yet!
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