I'm going to be painting my 91 firebird, my girlfriends 87 Camaro, and hopfully soon an 84 Trans Am I'm purchasing. I was planning on using a gravity gun since they have less waste. These are going to be my first paint jobs and I'm a little unclear on some issues. Some poeple tell me that I can't use a gravity gun for primer, base coat, and top coat. And others tell me I can use it for the entire painting process. What do you guys think? And which kind of gravity gun do you recomend? Any help and tips are greatly appreciated! Thanks guys! Jamie

 

AN HVLP (High Volume Low Pressure) Gun (AKA gravity feed) will work for primer base coat mid coat and clear coat. The catch is that you need a compressor about twice the size of one you would use for an old siphon feed gun. You also need to use all 3/8" fittings and hose and filters and requlators etc. that the air passes through to keep the volume of the air up. It is the Volume of the air not the pressure that atomizes the paint in an HVLP gun. If your compressor is undersize you can get away with spraying primer and base coat but you will not have enough air to atomize the clear coat.

So the answer is it depends. Check any gun you are going to purchase and make sure you have at least 25% more cfm capability in your compressor than the gun requires. Otherwise go with the siphon feed. Yes it uses more material to do the paint job but the results will be better if your compressor is not big enough.

Ric

 

Awesome. Thanks for the info. If anyone else has any keep it coming. I don't wanna miss something and have to redo the paint...

 

You can use the gravity feed for it all. Just remember to clean it real good between the coats. Also read up on the different tip/nozzle sizes. Since the primer is thicker, you would be better of going with a larger tip.

 

I have a cheap matco gun that I use for my primer I think its a 1.7 tip not sure. Than I have a sata jet for my base and clear. My compressor is a 60 gallon 2stage than I have it ran to another 60 gallon tank.. It works real good Don't have a prob with the air anymore...

But I use to have a 5 hp single stage comprssor I was able to paint a hole car but it would run the hole time I was painting

 

I'm looking at compressors and a HVLP gun as well, but I'm STILL not too sure about CFM requirements. The compressor I have picked out is a Coleman 6HP peak with a 33 gallon tank. 7.7 CFM @40 PSI and 6.0 CFM @90 PSI. Is that good enough for a HVLP type gun?

 

Ahhh I'm not sure but i think u are going to be cutting it alittle close. Just looked at some guns the lowest one was 11.4 cfm that was a shape. So i don't think 7.7 cfm will work..

 

I LOVE the SATA HVLP guns. I have a SATA Digital RP for base and clear and a SATA primer gun. Of all that I used, they are superior in quality. They aren't cheap.

The compressor is probably not gonna do it.

 

What would be a good compressor to get that I could use on almost all guns?

 

Yeah i love my sata to. (useing it right now)I got my as a demo gun so i saved about 200 bucks..

I would say at least 15 cfm. My last compressor was like 12cfm at 90 it worked but it would never stop running.