I'm wanting to change the color of my truck from Pebble Beige to Holly Green and, because I'm a DIY kind of guy, I want to do the paint work. Back when I was building kitchen cabinets for a living I sprayed the finishes using a traditional paint gun and compressor, so I'm not exactly a noob. BUT, I have never painted a car. So, here goes:

I want to go ahead and invest in a compressor that will allow me to paint my truck. All my old paint guns are long gone. What should I buy? I want to use the compressor for other air tools including nail guns. Does that rule out HVLP guns?

As a point of departure, I found this gun:

And this compressor (@ $500) promising an air delivery of 13.4 scfm at 40 psi : Kobalt 60-Gallon Air Compressor - Kobalt Tools

Any advise would be greatly appreciated. I'm looking to buy in the next couple of weeks.

Also, I live in the humid Southeast.

 

$500 for a 60-gallon compressor? That's really good. I'm gonna have to look into that.

Other items to consider: air/water separator or a dryer, auto-oiler, hoses, fittings (decide now because not all are the same), and a DA sander. I'd add a touch-up/jamb gun to the arsenal.

 

Thanks for the tips.

The compressor is at Lowes. Do you think I need that much compressor? It does seem like a pretty good deal.

C68

 

For HVLP, yes... they are air hogs due to the "High Volume" part of the equation.


Check to see if it can adequately power a 1/2-inch impact wrench at 90 psi like 200 ft. lbs. or an air chisel .. those are the real tests in my opinion. Sometimes ya need that much to loosen a dampener bolt or tighten a pitman arm nut. I darn near blew a brain gasket on the latter!


I have a water separator which uses toilet paper rolls.

 

Devilbiss is a good gun, I have a couple sets of guns but the Devilbiss is what I use and it does a good job. Hio Silver is right on as far as the add ons go, I would also add Disposable In Line Air Filter to go at the gun. Check out these guns from Eastwood it is a three gun set, same guns your looking at but also has the touchup gun. Devilbiss 3-Gun Kit - Air Spray Gun - HVLP StartingLine Gun - Eastwood

 

Save as much money as you can and get as big an air compressor as you can afford to buy.

It's far better to have a bigger air compressor than you need than to have one that's to small to do what you're trying to do with it.

I have a Husky, continous duty, two-stage, 7.5 hp motor with an 80 gal tank that will maintain 23 SCFM @ 90 PSI. It will go from an empty tank (0 PSI) to 175 PSI in about 4 minutes. I bought it at Home Depot.

The most demanding tool I have is a bead blast cabinet (48" wide cabinet from TP Tools). A bead blast cabinet is like a wide open air line leak on a compressor. I never have to stop and wait for my compressor to catch back up. I can blast continously until the part is cleaned.

--don't use the same air line on a paint sprayer that you use for your air tools.


This is the company I bought my bead blast cabinet through. Here is a very useful illustration from them on how to plumb your air lines from the compressor, to keep moisture out of your lines.

https://www.tptools.com/tech-metal-piping.dlp

 

I painted my truck with a $30 harbor freight gun. Practice practice practice. The new guns are easy to get the hang of. I have a relatively small compressor that I use for everything. The cups on these guns are pretty small so it can catch up when you refill.

 

Looking at air dryers online and there seems to be a pretty wide price range out there. This one seems to be reasonably priced ($220 - $180 on sale) and gets good reviews: DVB QC3 Air Filter and Dryer - Desiccant Air Dryer - Air Compressor Filters - Eastwood

How much do I need to spend?

 

I have a Cambel Hausfeld (spelling) I probably paid $20 for 10 years ago. I always use a fresh in line filter at the gun and have never had any fish eyes while I'm painting. I have never separated air lines and my compressor runs pretty much the whole time I am painting but it keeps up. I am not a painter by trade but have done 6 or so full paint jobs with my rig and have never had any paint issues from my set up. I would invest the money in materials instead. ( just my opinion)

 

You don't have to spend that much. I run a filter/dryer at the compressor then one where I come off my shop piping when a disposable inline moisture filter between the gun regulator and the gun. The main thing use 1/2" filters in the line, and don't use quick coupling on lines when painting, it doesn't matter how much air your compressor will put out if you restrict the lines going to the gun. I have two 60 gal compressors in my shop one came from Lowes the other is home made. The Lowes compressor has a Desiccant Dryer on it, the home made compressor has cheaper Harbor Freight filters and that is the one I use for painting. 1/2 in. Standard Air Filter

 

Fish Eye is mainly caused by a spot of oil, grease or wax on the surface or in the line. As ultraranger said earlier "don't use the same air line on a paint sprayer that you use for your air tools."

 

Okay, that's good news. This all seems very 'do-able.'

My plan, after I'm set up with the equipment, is to practice on surfaces like the underside of the hood or maybe a tool box painted to match the truck. Once I feel confident I'll move on to painting the more important stuff.

I'm pretty picky about finishes and I was able to get nice, even finishes with sprayed enamel paint on wood. It'll be interesting to see how spraying auto paint on metal compares.

 

The main thing is learn your gun and its setup. Here is a pretty good write up that does a pretty good job explaning how to set the gun.




Paint Gun Adjusting




This may sound trivial to an experienced painter but the fact is very few painters know how to adjust their paint gun. This one item separates a sprayer from a painter more than anything else. The fact is a painter that knows how to fine tune his paint gun will turn a lot more hours and have a lot less problems because he is controlling the paint and is not letting the paint control him. This is why 80-90% of the painters today hate to spray High Solids clears. They vision runs or orange peel and if you don’t adjust the gun properly this is what you will get make no doubt about it.

What tip should I use?
My personal feeling is for basecoat a 1.3 or 1.4 and for clear 1.4. The exception on the 1.4 for spraying clear would be certain HVLP guns where a 1.5 is made for spraying clear. And of course a true painter is only going to use gravity feed gun. Leave the old siphon feed guns for the enamel sprayers that they are made for, as these guns have no place in today’s body shops that are using Urethanes and Polyurethane’s.

What happens with an improperly adjusted paint gun?
If you’re applying basecoat chances are you’re applying it way too heavy and your blends are showing, your metallic are not lying down or standing out like they should so your color marches are a problem and the base is drying slower between coats than it should.

The number one clue the basecoat is going on too heavy is if you’re having a dieback problem with the clear after setting overnight (trapped solvents). If you’re applying clear the clear is controlling you instead of you controlling the clear. With a High Solids clear you try to spray it wet enough that the orange peel will flow out but hope that it doesn’t flow so much that it runs on you. The next day you tend to have a clear that looks cloudy or milky because of the trapped solvents and it requires a lot of wet sanding.

The benefits of adjusting the paint gun properly will be faster application of paint and you will know what the final job will look like when you spray it and not have to guess.

How do I properly adjust my gun?
Place a piece of masking paper on the wall, then set the fan how you like it. Adjust the air pressure to the rate that you plan to spray with. Screw in the fluid adjustment all the way. Hold the gun from the paper the distance that you would normally spray (usually 6-8 inches) and give the trigger a quick squeeze and release. If anything comes out of the gun it should be very little and dry.

Turn the fluid out one full turn and repeat this procedure half a turn at a time until you are getting an even pattern and the paint is even in build. If it is metallic the metallic should spray even as well.

At this point go to a rocker or bottom of a fender on the car and make a 12-inch pass. You will most likely have to back the fluid out one-half to one full turn to spray at the speed you want then fine tune your air pressure.

Now the gun is very close in adjustment, you should be able to lay the clear orange peel free with out running it, and metallic should spray even and wet with out much effort. Keep in mind this is not your last adjustment; every base color will spray a little different and may require a half a turn in or out for the new color. If you're going from a high solids clear for an all-over to a spot repair clear you will need to make a minor adjustment again.

A simple formula to remember is orange peel is fluid adjustment and run control is an air pressure adjustment. If you’re getting a few runs try upping the air pressure 5-10 pounds more.

One final note, spend the money for a good set of paint guns! This is your career and the paint gun makes or breaks you as far as labor hours turned. NASCAR drivers don’t buy their race engines at a parts store to save money, so why would a painter want a $200 gun? Spent the $400-600 for a good base gun and again for a good clear gun the payback will be faster than you think. You will always get what you pay for with a paint gun!

 

Thanks, I had forgotten a lot of that and never knew the rest. Good advice. I would definitely rather spend a little more on good tools than fight with cheap ones and get poor results.

I don't know what a good paint job costs, but I figure I should be able to get decent results and come out with tools that I can always use later for less than I would pay a shop to do it.

 

I'm going to echo buy the biggest compressor you can afford. Especially if you plan to do any sand blasting or run a DA.

As a Texan I can appreciate the humidity issue. I solved the problem with a Ford A/C condenser from a junk yard. My compressor tank stays cools and moisture free, which is great for sandblasting and painting. You can read about my compressor setup in my Camaro write up at:
1972 Camaro Project Start to Finish Post - NastyZ28.com

I used three different paint guns. HF for the primer, Devilbiss Finishline 4 for the base coat and a Devilbiss Plus for the clear coat. However, in the past I have had good results shooting single stage paint with a sub $20.00 HF gun. Honestly I think it is more about the prep work.

When you are doing prep work, just keep this thought in mind, the paint does not hide any imperfections, it just adds color.