Air tank longevity (how long can i spray for at "x" pressure with "y" tank)

[shakes]

Air tank longevity (how long can i spray for at "x" pressure with "y" tank)

Hey all,

Slightly strange question which I think I know the answer to but am hoping someone can confirm for me. If I have two compressors, both with 8 gallon air tanks, but one compressor can put out 60psi and one can put out 180psi will the 180psi spray for three times as long as the 60psi compressor at 20 psi? Or something along those lines?

Also can anyone explain to me how I could make my own external air tank for airbrushing and fill it with my current compressor? I'm wondering if I can just buy a big tank and fill it myself. If I did this and got say a 12 gallon tank could anyone give me an idea how much continuous spraying I could achieve at 20psi if I could only get the tank up to a pressure of 60psi?

Cheers, Shakes.

 

[Einion]

Slightly strange question which I think I know the answer to but am hoping someone can confirm for me. If I have two compressors, both with 8 gallon air tanks, but one compressor can put out 60psi and one can put out 180psi will the 180psi spray for three times as long as the 60psi compressor at 20 psi? Or something along those lines?

My guess would be they'd both spray for around the same amount of time. Pressure is pressure - independent of other features - with tanks of equal volume when you're spraying at a given PSI they should hold the same volume of compressed air (approximately). But I'm not sure if different compressors hold air at different settings and the valve is then responsible for the accurate pressure of the supplied air.

Also can anyone explain to me how I could make my own external air tank for airbrushing and fill it with my current compressor? I'm wondering if I can just buy a big tank and fill it myself.

This is doable, but not necessarily straightforward. You'll probably get the practical answer to this in due course but in the meantime if you do a search of the forum using some combination of keywords that'll bring up relevant prior threads, pretty sure most or all of what you need to know has already been outlined once or twice.

If I did this and got say a 12 gallon tank could anyone give me an idea how much continuous spraying I could achieve at 20psi if I could only get the tank up to a pressure of 60psi?

No single answer to this as pressure is one thing but the throughput of the gun is what's relevant here. Think about the difference in spray volume between a big spraygun and a fine-tipped airbrush hooked up to a compressor set at 20PSI, there's definitely more air coming through the spraygun.

Einion

 

[airhead]

Been way too long since thermodynamics and differential equations. But yes, with two tanks of the same volume but of different pressures, you'll shoot longer out of the tank with more pressure - all other things being equal - assuming your pressure regulator is decent.

Adding a tank to a compressor is somewhat dangerous. I've seen the aftermath of an air tank exploding. Similar to a mine.
But, home centers sell an independant air tank - generally with an inflation valve (tire valve) on one side to air it up and a hose and guage. You'lll still need a regulator and a moisture trap.

http://www.homedepot.com/buy/speedway-5-gal-portable-air-tank-7296.html

Why go to all that trouble when you can purchace a compressor with all that (tank, auto shut off, regulator, moisture trap, hose, quick connnects, maybe even a stapler or nailer) for about the same money you can trick out a tank?

 

[shakes]

Thanks for the prompt answers guys, very helpful! The reason I was asking about a tank is because I havent been able to find a compressor with a tank that I deemed quiet enough for a reasonable price. I was considering a paasche d3000 but I don't feel it to be powerful enough.

Lucky for me that just changed! I'm on vancouver island and up until recently I've never been able to find a quiet compressor from any of the local retailers. Home depot now has the "6310 1.0hp 6.3 gal ultra quiet oil-free steel tank air compressor" from california air tools for $200 bucks. Shoots up to 120psi, 2.35CFM @ 90. Seems like everything I would need and most importantly is registered at about 60 decibels which I feel is an acceptable noise level!

Do you have any thoughts on this compressor at all?

Cheers, Shakes

 

[airhead]

There ya go.
Another happy airbrusher using a standard air compressor.
The regulator/water trap looks kinda cheesy. I prefer separate units. But other than that, it should get the job done.

 

[KruleBear]

As far as storage tanks, just make sure they are pressure vessels ( they will have some type of code stamp) and a pressure relief valve (similar to a water heater tank) and you should not have much to worry about.

For a fixed volume vessel pressure change is proportional to mass (and temperature) of air in the vessel. I.e. When you drop the pressure through your air brush you will have more mass that relates to longer brush time.

 

[QuietiManes]

The GMC/CAT compressors have rave reviews all over the place. The 6310 should serve you well, I wish they sold the larger tanks in aluminum, check out the 4610A if you'd prefer aluminum at the cost of less storage.