Official Luthiers Forum!
http://www.luthiersforum.com/forum/

Questions on PSI/CFM and sprayers
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=29997		 Page 1 of 1
Author:  sprouseod [ Sat Nov 20, 2010 8:38 am ]
Post subject:  Questions on PSI/CFM and sprayers
I have a $120 HF compressor 2HP rated at 5 SCFM @ 90psi and 6 SCFM @ 40 PSI. I have a Walcom HVLP Slim rated which recommends 28psi/2bar on the sprayer and in the manual specifies 6.6 CFM. My question is, as the PSI comes down does the CFM go up? I don't quite understand the relationship. Bottom line does this compressor have enough juice to properly spray waterborne finishes with this gun?

thanks
Richard
Author:  woody b [ Sat Nov 20, 2010 9:07 am ]
Post subject:  Re: Questions on PSI/CFM and sprayers
Quote:
My question is, as the PSI comes down does the CFM go up?


Yes, but it doesn't really matter. Guitars are small and it doesn't take long to put a coat of finish on them. Your compressor will be more than big enough as long as you're not spraying something big like a car, or more than a couple guitars at 1 time.
Author:  Rolfe [ Sat Nov 20, 2010 9:24 am ]
Post subject:  Re: Questions on PSI/CFM and sprayers
I think the answer to your question is: no, as the pressure, psi, goes down the volume, cfi, does not go up. But that doesn't matter in your case. Your compressor is marginal, but it will do the job with that gun, which is a very good gun for guitars. If you ever feel flush, the new Walcom EGO gravity feed gun is even better. An important thing in your case is to be sure you have some good filtration between the compressor and the gun.
Author:  Fred Tellier [ Sat Nov 20, 2010 10:04 am ]
Post subject:  Re: Questions on PSI/CFM and sprayers
The ability to supply a constant CFM does go up with a drop in the required PSI. HVLP guns require a pressure at the gun from 20 to 40 PSI so until the pressure drops below the set point of the regulator the compressor can supply enough air volume. As stated above we do not spray for long periods without releasing the trigger so the compressor is able to keep up the pressure in the tank. Your compressor is plenty large enough. I use a regulator at the gun and add an inline moisture trap filter at the gun to keep the air clean and dry.

Fred
Author:  sprouseod [ Sat Nov 20, 2010 11:57 am ]
Post subject:  Re: Questions on PSI/CFM and sprayers
Rolfe wrote:
An important thing in your case is to be sure you have some good filtration between the compressor and the gun.


Anything in particular you recommend? How do you know if you have water in your system?

thanks
Richard
Author:  woody b [ Sat Nov 20, 2010 12:39 pm ]
Post subject:  Re: Questions on PSI/CFM and sprayers
I've got a water trap at my compressor, and another inside my finishing room. These are just simple water filters I got off the Mac tool truck. I believe Lowes has something similar. I also use one of these small disposible filters at my gun.
http://www.tcpglobal.com/spraygundepot/itemdetail.aspx?itemno=SHA+8100
Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/