Compressor

69NoH20 · Post by **69NoH20** » Thu Jun 26, 2003 11:51 am

I'd like to start getting supplies together to repaint my car. I looked at the Sharpe web site and it looks like their spray guns need around 12 SCFM air flow. I can't find a Craftsman that has that kind of capacity. Did i read the specs correctly?

Pete65 · Post by **Pete65** » Thu Jun 26, 2003 11:57 am

you probably read them correctly...

my crafstman 4.5hp puts out 6.5SCFM @ 90PSI. I have a craftsman spray gun that says it will work with the output of my compressor but I've been told that I'm going to have to paint in sections and even then I might not have enough air.. I'm going to try it anyway. One site I was at the dude said it's not worth it using anything less than 20SCFM @ 90PSI, maybe that's if you want to paint the whole car?? I don't know, I'm pretty new to this too.. you can check out the thread that I started about my first paint job and there are some good links to different painting related questions...

http://www.shoptalkforums.com/viewtopic.php?t=49745

good luck and post any findings back here for the rest of us!

Jame · Post by **Jame** » Thu Jun 26, 2003 3:14 pm

Most guns operate at a much lower pressure than 90 psi -- like 30-50psi. Overwise the overspray would be awful. -- A compressor must "keep up" paint flow will not allow for pressure drops. A 6hp, single stage of any quality --9.5-12 cfm will suffice. A tip I discovered from a body shop is to set the regulator on the compressor at 90psi then have an inline regulator on the gun set at 30-50 psi -- Good flow to gun then can adjust pressure as needed at gun to produce results.

doc · Post by **doc** » Thu Jun 26, 2003 7:19 pm

It would be nice if we all could afford an $800 compressor that flows a steady 20cfm, but for most of us that's not in the cards. A much smaller 4 or 5hp compressor will do the job. As stated above, most HVLP guns require 30-50 psi at the gun. Get a cheap pressure guage from Harbor Freight to put inline just ahead of your gun to monitor this. You can control the pressure at the compressor. Or put pressure control and guage at the gun and set compressor at about 90psi.

The drawback to the smaller compressor is that it's going to run all the time while your painting trying to keep up and the noise stinks. Every little while you're going to have to stop to let the compressor catch up. But definitely doable. For the hobbyist who just paints a single car or a few parts once in a while, a smaller compressor is sufficient.

Now when you decide you want a DA sander to speed up the prep work, then you'll really wish you had a bigger compressor. The sander requires much more air to run than the paint gun and the compressor has to really work to stay caught up. If it's anything like mine, it'll be sand for two minutes, then wait two minutes. But I'm not doing it for a living..... I say start paintin' !!

Dwarfstar · Post by **Dwarfstar** » Thu Jun 26, 2003 8:57 pm

I saw somwhere a mod kit for 40 horse motor that turns 2 cyliners into a air compressor. I cant recall the cfm but it was fairly large ammount of air this baby would make. The kit didnt seem cheap ither but for a vw Expert with parts all around maybe just seeing one kit would let one make more Sortof like it. Just a thought.

Vintage Werks · Post by **Vintage Werks** » Fri Jun 27, 2003 6:05 am

I'm not going to say it was great but when I started my restoration shop I was using the 6.5hp 60 gal compressor from craftsman and I was able to restore and paint many cars with it including a custom paint job on a new corvette convertible but I have also used a much smaller compressor to paint a 2 tone paint job in a guys garage in SC. I would say get the biggest compressor you can afford and work with it and practice spaying to get use to presser drops before spraying your car

Cornbread · Post by **Cornbread** » Fri Jun 27, 2003 7:35 am

I have the Craftsman 6hp 40 gal compressor. I haven't used it yet to paint but I considered this before buying it. Everyone I spoke with said that the output provided by this compressor will be more than adequete for almost all HVLP guns. Plus, it was only around $300. They have a Professional series that is a little more with a bit more output if you are interested.

Cornbread · Post by **Cornbread** » Fri Jun 27, 2003 7:40 am

I checked out the Craftsman site real quick. The most expensive HVLP gun they have requires 6.0 SCFM at 40 PSI, so I think you should be alright with a 6HP compressor.

Bobnotch · Post by **Bobnotch** » Sun Jun 29, 2003 8:01 pm

Yeah, my Devillbis gun (a HVLP GTI model) operates at about 25 psi , for both color and clear. They actually recommend less than 30 psi. With my air commpressor (an old Cambell Hausfield 7 hp 80 gallon), it only cycles on toward the end of the car being painted, or maybe twice if its a bigger car or the jambs and under the hoods being painted. When I went looking for a commpressor, I looked for something I was going to buy once and use for the rest of my life, and I've already had it over 5 years now.

doc · Post by **doc** » Sun Jun 29, 2003 8:07 pm

Bob, do you remember what you paid for your compressor? Has anybody seen those compressors on ebay from some small outfit in Ohio (i think) that claims to make the world's best compressors? Any opinions? The claims are intriguing.