Spray Gun Recommendation

[Larry M.]

I need to purchase a paint spray gun for use with a 30 gallon, 5.5 HP air compressor.

The gun would be used for spraying interior parts (dash panels, steering column, console pieces, etc), and occasionally some latex-based paints on furniture pieces.

My prior gun had been the 'old-style', which drew the paints up from a jar below the spray mechanism.

Any suggestions are appreciated.

Thanks,
Larry

[Michael G.]

Re: Spray Gun Recommendation

I believe your needing two types of spray guns to do what your needing Larry. Latex paints will have a much thicker viscosity than what you would be spraying on the interior. Of course you could get a larger tip for the latex as the interior paints will need a smaller tip. Myself, would want a gun specific for the job however that would be your call. Many good brands available however to do interior pieces no need to get a top dollar spray gun. I've spent less than $50.00 for a HVLP gun and gotten great results....basically a no-name branded gun.

[Steve G.]

Re: Spray Gun Recommendation

Just as a qualifier, I'm a self taught amateur that's been doing my own painting for about 15 years. I'm happy to share what I've learned, but hopefully a pro will jump in to correct/add to.

The compressor spec you want to be most concerned with is volume, how many cfm your compressor makes. Guns are rated by the volume of air they use. If your gun is using more cfm than your compressor is making the size of the tank will determine how long you can paint before your gun pressure drops out of proper range.

You have what's known as a suction feed gun. Most guns sold today have the cup on top. That's known as a gravity feed. The advantage is that you can use every drop of paint. At $500/gal, that can be important to some people.

As to the actual gun itself, if yours is an older suction gun it is probably what is known as a conventional design. These used higher air pressure and lower volume of air. Their disadvantage is that they are terribly inefficient. They put a lot of paint in the air compared to what goes on the project. Their advantage was fine atomization which meant easier to achieve a smooth finish. In most areas you can still buy conventional guns.

Most of today's guns are HVLP, High Volume, Low Pressure. These guns put a lot less paint into the air and more on the project. But they require a greater volume of air. You can get them in a gravity feed or a suction feed like your old gun.

There is also a category called compliant. In order to be called HVLP the gun can not have more than 10 psi at the air cap (not at the gun gauge. You can not measure air cap pressure, it's a design thing). Compliant guns do not meet that requirement, but are close. The combine some of the benefits of the old conventional gun with some of the HVLP benefits and put out an overspray volume that meets the emissions requirements of most jurisdictions.

When it comes to choosing a brand one thing to keep in mind is the cost of the different tips. For most automotive finish work a gun tip of 1.2, 1.3 or 1.4 is appropriate. But a thick paint like a high build primer wants a tip size around 2.0 or larger. I'd imagine your latex finish is even thicker than the high build primers. Most guns come with 2 or 3 of the fine tips, You will have to buy the large tip for your primer and latex. On an expensive gun those tips can be incredibly expensive.

My first gun was a Porter Cable. It was an inexpensive HVLP, gravity feed gun that sprayed well. When I bought my extra tip parts they were quite reasonable.

As my skills improved I bought a better gun, a Devilbiss GT something ( I can't remember the specific model). It is a gravity feed compliant gun. I was disappointed at first. I had learned to spray quite nicely with my cheap old gun. I had to relearn with the newer compliant gun and the end products wasn't any different. It's not about the gun, it's about the operator was what I learned subsequently. Parts for my Devilbiss are very expensive. But you have more options in terms of things like disposable cup liners, tip sizes etc.

I bought a super cheap Astra finishing gun. Piece of crap that leaked all over and couldn't maintain a pattern.

Long story condensed, the Porter Cable (Black and Decker owns them) was a respectable gun for a reasonable price. I still use mine for primer and other jobs where I need a big tip. I'd highly recommend it if they are still available. I bought mine, as I said, about 15 years ago, but as of a couple years ago I could still buy parts for it.

Steve

[Larry M.]

Re: Spray Gun Recommendation

Mike and Steve,

Thanks for your thoughts.

The cfm rating for my compressor is 8.6 scfm @ 40 psi, and 6.4 scfm @ 90psi. From what you know, are those ratings sufficient for powering HVLP sprayers? The compressor did power my old conventional style, suction-feed gun.

Steve, you mention that HVLP guns are available in gravity- or suction-feed. Is there a benefit of one style over the other. And thank you for the detailed info you provided.

Larry

[Robert D.]

Re: Spray Gun Recommendation

Most spray guns that i have used are rated at 12 to 14 cfm But if you are spraying small parts with short spray times with a low pressure gun then what you have may be adequate. if you intend to spray whole cars or larger panels then the gun will overwhelm the compressor and your atomization will end up being spatter. As for guns, harbor frieght has some inexpensive guns that have gotten great reviews. I also have a starr brand gun that i bought 15 years ago that sprays just as good as any sharpe devilliiss or sata gun which are 5-10 times more expensive. just keep it clean and lubricated and it should last forever. As stated earlier i dont believe your going to get a gun which will spray both laquers/enamels as well as latex paints the latex paints will require a much larger nozzle size and propably more pressure. i would recommend gravity feed and i also use 3m disposable cups which makes cleanup much easier.
Good luck
Bob

[Steve G.]

Re: Spray Gun Recommendation

Mike and Steve,

Thanks for your thoughts.

The cfm rating for my compressor is 8.6 scfm @ 40 psi, and 6.4 scfm @ 90psi. From what you know, are those ratings sufficient for powering HVLP sprayers? The compressor did power my old conventional style, suction-feed gun.

Steve, you mention that HVLP guns are available in gravity- or suction-feed. Is there a benefit of one style over the other. And thank you for the detailed info you provided.

Larry

The only downside I've come across with a gravity feed gun is getting into some places with the cup on top. I have limited experience with suction feed, but I'm sure you'd come across situations where you wished the cup wasn't on the bottom. Clean up is definitely easier with a gravity feed, and as Bob said, the disposable liners are a great option that will also allow the gun to be turned right upside down if you need to. No venting required. the liner collapses.

Steve

[Larry M.]

Re: Spray Gun Recommendation

Bob and Steve,

Thank you for your additional information.

I will not be spraying any cars or large panels, so the gravity feed HVLP seems appropriate for my usage. Easier clean-up with a disposable liner is also a plus.

I do have a question on this phrase: 'Clean up is definitely easier with a gravity feed, and as Bob said, the disposable liners are a great option that will also allow the gun to be turned right upside down if you need to. No venting required. the liner collapses.'

Am I reading it correctly that the gravity feed gun will operate upside-down? Not that I expect that I'll need to do that; I'm just looking to see if I understand the operation correctly.

Larry

[Mike E.]

Re: Spray Gun Recommendation

Larry,
Couple of years ago I picked up this set of HF cheapo guns.

http://www.harborfreight.com/2-pc-professional-automotive-hvlp-air-spray-gun-kit-61472.html

I'll probably be lambasted for recommending cheap Chinese tools, but I've painted a bunch of small parts and my frame with them. They lay down epoxy primers and single stage urethanes fine. Are they the build quality of a SATA or Iwata? not even close. The bigger one comes with a 1.4 & 1.8 tip for heavier paint, I'll admit I've never shot anything like latex with them.

Would they also hold up for day to day usage probably not, I also would not paint a entire car with either one of these guns, but for the hobbyist they should work fine, without breaking the bank.

As far as disposable liners go, I think they would be more trouble then what it's worth. Painting anything with a gun can get messy if your not careful.

With any gun I would also recommend these accessories attached to the gun at the air supply inlet. And some type of drier upstream too wouldn't hurt.

http://www.harborfreight.com/digital-air-flow-regulator-68245.html

http://www.harborfreight.com/Inline-Desiccant-DryerFilter-68215.html

Mike

[Robert D.]

Re: Spray Gun Recommendation

Larry,
The spray gun with disposable 3m liners are removed and thrown away when done. there is an adapter that is placed on the gun in place of the metal cup. the disposable cups are very soft and fit inside a harder plastic cup. the softer disposable cups also have a built in filter wich is a plus.when the paint is mixed you fill up the disposable part put the cover on it and close the harder plastic cup around the softer part. its a simple thing alot easier than im explaining it. as you spray paint the inner cup collapses so you dont need a vent as in a metal cup so yes you can spray upside down which is awesome! i do it all the time. also these cups come in several different sizes i think the ones i use the most are one pint or half pint sizes perfect for what you want to use it for. these things rock i bought a box of them with the cups about 5 years ago and still have 1/4 of them left. used them for about 3 restorations so far
hope this helps
Bob

[Steve G.]

Re: Spray Gun Recommendation

Bob,

Did you buy your cup liner system online? I've never used them, but think I want to start.

Steve

[Robert D.]

Re: Spray Gun Recommendation

Steve
i bought them at my local auto paint supply store. you can get them online there called the 3m pps system you need the adapter for your spray gun and the cups which come in a box of 2 which are a one time investment. then you buy the disposable liners and caps with the filter built in which come in different sizes to match the cup you have. a box of liners is a little pricey but i bought a box that lasted me years