I'm going to buy a spray gun and I'm told HVLP is the way to go. My compressor will do 8 bar (115 PSI) which is more than enough but will only do 7.3 CFM.

The guns I've seen need 8, 9, 11 and 15 CFM according to their data.

What will the effect be of using a gun that takes more air than I can feed? Does it just mean I have to wait a second or two between sprays or will the paint come out in a dribble?

[Edited on 8-2-2009 by smart51]

For occaisional use go the HVLP spray station route rather than a compressor.

Prices vary from about 25 pounds up tto several hundred -- the low cost units still give very good results provided the correct nozzle size is used.

Main brands are Wagner, Apollo and Earlex.

Earlex are the market leader they offer good technical back up and supply diffeent nozzle sizes for spraying different materials.

What pressure does the gun require? Mine uses up to 50psi but I usually run at 40psi on the regulator separator. As long as it can maintain the pressure you will be alright to wait while the tank fills back up. I think the figures given for cfm are more of a guide to compressor size than absolute requirements for the gun. Mine is a gravity feed HVLP as I now prefer these, you don't need as much paint in the cup.

The compressor was bought for me as a gift when I left my last job. I really ought to use it.

The Sealey 741 needs 3 bar / 43 PSI and uses 16 CFM (I guess that's with max, with the gun spraying continuously).

The Sealey 751 is more expensive but needs 15-28 PSI and 2.8 - 7.9 CFM.


Is the compressor rating the max air flow you can take and it still maintain max pressure, or will it deliver 16 CFM if demanded but the pressure will drop.

If I can use the gun for a couple of minutes until the tank pressure drops to 3 bar then wait a minute or two before I can continue, then that won't be so bad.

[Edited on 8-2-2009 by smart51]

http://cgi.ebay.co.uk/Earlex-Spray-Station-1900-HVLP-Paint-Fence-Sprayer-BNIB_W0QQitemZ2902941422

If the gun requires a high cfm you will find that you run out of pressure quickly I have to run two samll compressors on 8-9 cfm the other 7cfm the gun can outrun the compressor not good if your halfway through a panel