Air pressure setting for nail gun vs sprayer?

[Doug Swanson]

Hi,
I was wondering what pressure do you set your regulator to when you are using a finish nailer? Also what level do you typically set it to for a sprayer?...specifically a sprayer that has the cup mounted to the top of the spray gun when you are spraying shellac.

I have a horizontal 20 gallon tank....(I think it is 20 gallon...18" in diameter...3' long?)

Thanks
Doug

[Rich Engelhardt]

Nail guns - it varies by the brand.

Better guns will usually have a more efficient air motor and require less pressure.
Cheap guns will usually need more.

I run my Bostitch F28WW framing nailer at between 75 and 80 psi. My contractor buddy runs his PC 350 framing nailer at 90 to 100psi.

My el cheapo 18 ga Coleman brad nailer needs 100 psi to work.
My 18 ga Craftsman only need about 85 psi to do the same work.
My Tradesman ( an older Lowes private lable of some other higher quality name brand - couldn't tell you who though) only needs 80 to 85 psi.

16 ga PC nailer usually runs @ 90 to 105 psi.
15 ga Grex finish nailer - same - 90 to 105 psi.

23 ga PC pin nailer is all over the place, depending on the length of the pins. 99% of the time I run 3/4" pins in it @ 90 psi.

Sorry I can't shed any light on the sprayer, other than to say volume of air is more important than simply pressure.
Compressors usually give you two figures for volume. One at 90 psi and one at 40 psi.
For regular conventional spraying (not HVLP), most guns will need ~ 11 SCFM @ 90 psi to run properly.

The top mount gun you have should have some documentation that tells you how much air and at what pressure.
Somewhere on the compressor there should be a plate that gives you the delivery.

[Tom Ewell]

90-100psi for all nailers I've used as most have on board adjustable depth settings.

My paint sprayers all use an inline regulator right at the gun which is set to spec for finish type, main line into this regulator is left at 90-100

As mentioned, guns will vary as to cfm/psi required, check the manufacturers spec.

PSI setting at compressor will differ at hose end, ie. regulator at compressor set to 100psi can end up being closer to 80 psi at the tool depending on length and diameter of hose.

[Steve Keathley]

I have a Rigid brad nailer that works very well at 80 psi with a 50' hose. But I do think it varies by brand as others have said. Can't help you on the sprayer I'm afraid.

[Peter Quinn]

Nailers, depends on the gun, usually 75-90, more often 90. For the spray gun, the manufacturer should offer a recommendation, and you should step down as close to the gun as possible. For that compressor only an LVLP is really going to work, or perhaps an old school high pressure gun, but little reason to waste that much finish these days. My hvlp gun calls for 29 psi. I run tank psi at 90, step down in the spray room to 29 just ahead of the gun, run the pressure knob on the gun wide open. I had a mini regulator on the gun but that's just more weight and size I don't need on a gravity feed conversion gun. So check the suggestions from your guns manufacturer, if they don't offer one, it may be time for a better gun. Some of the new LVLP guns will work on very low scfm's and should shoot a decent finish even with a small compressor. Keep in mind a long, narrow, or otherwise restrictive hose may lower performance, ,and you don't need that if your air is already limited. I like at least a 3/8" hose to the gun if it's more an 15' to the compressor. I'm running a 3/4" copper line to my spray room and a 10' leader from that, with filters and a regulator in front of the gun, a disposable water filter on the gun.

[John Coloccia]

I run most of my stuff at 90 PSI, but I run my spray booth at 120, down to maybe 25 or so at the regulator in the booth. If you try to run your compressor at 25 PSI through 50 feet of air line, you will have very poor performance at the gun.

[Peter Quinn]

Just looked at my setup, been a while since I actually though about it, like John I'm at 125 psi from tank to spray room, or full tank pressure. Only the lines going to other tools are set to 90 psi.

[Doug Swanson]

Thanks everyone for your replies. Very helpful and educational. Currently I just have the regulator at the compressor...I'm looking at having that go into a manifold with an appropriate filter/regulator.

Thanks again
Doug