Spraying Finish with a Small Compressor

A finisher wants to spray small amounts of moulding and face-frame stock, but has only a small compressor. Solution? A mini gun. November 25, 2008

Euro cabs are my main area of work. I will be doing a kitchen using pre-made/finished doors from Walzcraft and pre-finished ply. Due to Walz's high prices on face frame stock and crown, we have decided to finish ourselves with Sherwin Williams cat lacquer. I'll probably be doing 20 or so pieces of 8'x2" face frame stock. With a small 1.7hp 17 gallon compressor 3.8cfm @ 90 , 5.6 @ 40, can I expect good results if adequate patience is taken in letting the compressor recharge and cool occasionally? The gun is a Finex FX300 which likes about 11cfm at its operation PSI. What can I do to increase my odds of good results?

Forum Responses
(Finishing Forum)
From contributor R:
You have absolutely no chance of spraying with your current gun if it requires 11 CFM and you have a 1.7 horsepower compressor. To get 11 CFM delivery, you need at least a 5 horsepower compressor and a 25 or 60 gallon tank. My advise, look for a cheapie gravity feed gun with low CFM requirements.

From contributor J:
You should be able to spray, but only for short bursts, maybe 1 minute or two before the compressor can't keep up and pressure falls off. This may or may not prove acceptable depending on how much you need to spray at one time, the thickness of your paint, and how little air pressure you can get away with using. Try a bit of retarder in your finish to help it flow out and resist orange peel. That way you can drop the air pressure a bit lower than normal to try to maximize your spray time. Of course, before you start the job, run some test pieces.

From contributor D:
Use a MiniGun. The ASTRO 4020 will definitely work for this application and only uses 4 cfm. It has a four to six inch fan and for molding is the nuts. The only problem you will have is keeping the relatively small cup of this gun filled.

From the original questioner:
Thanks for the info. I'm kind of digging the mini gun. I could see the constant filling of the cup being a pain, but I won't be using this all day every day. The short spraying sessions with the full sized Finex would probably work, but would probably stress the compressor.

Would the 4-6" fan of a mini gun work for a 96"x24" 1/4" ply skin? There is only one of these next to a fridge, and the rest of the ends are raised panel finished ends. I may have to just use the Finex for this, but it's one more setup and cleaning.

From contributor D:
The MiniGun will not work for that large of an area. You'll need the full size for that.

From the original questioner:
Okay, I ordered the Astro 4020 with plastic cup and 1.2mm tip along with a Sharpe diaphragm regulator. Thanks for the advice.