# paintball or scuba air tank setup?



## mr sarcastic (Nov 2, 2006)

i got my hands on a paintball air tank, and i've been thinking about attempting to use it as a tank in my mk5. my plan would be to eliminate the entire compressor and conventional air tank stuff, and run my entire setup on a high pressure tank. most paintball tanks are filled to 3000psi, have an adjustable regulator with a safety release so the entire 3000 psi cant be released on your gun (air ride setup in my case). same with scuba setups, just a bigger tank. 
so, anyone have any guess's as to how long a tank like this would last before needing a refill? refilling is no more then $5 a shot, but if it needs to be done weekly that'd be a pain and not worth it. i'm not to knowledgeable about air volume/flow/psi and all the technical stuff. but just looking at the specs on most bottles, it looks possible. for example this tank can shoot 650 shots at 800psi. so if you dial down the pressure, the count would go up. also, here's a little tech info on how the regulator works if anyone is interested. how a regulator works


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## John Reid (Jun 30, 2010)

I'd love to find out if this is doable, since I don't have the room in my JSW trunk for a typical tank (subs in trunk sidewalls, amps, spare,etc.)

Being able to use such a small tank would be nice...


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## [email protected] (Jan 26, 2006)

The air doesn't last long in a scuba tank. depends how much you use it.
but I would say every 4-5 days you will need a fill.


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## theAntiRiced (May 7, 2005)

You'd need to run flow controls and small lines for sure, otherwise you'll over-inflate the bags higher than you want to be and could quickly exceed their recommended pressure.

Running without a compressor would constantly worry me on a daily driver. The chances of you being randomly stranded would be huge, and it's not like running out of fuel where you could just go to a gas station and put a gallon in a can.


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## mr sarcastic (Nov 2, 2006)

theAntiRiced said:


> You'd need to run flow controls and small lines for sure, otherwise you'll over-inflate the bags higher than you want to be and could quickly exceed their recommended pressure.
> 
> Running without a compressor would constantly worry me on a daily driver. The chances of you being randomly stranded would be huge, and it's not like running out of fuel where you could just go to a gas station and put a gallon in a can.


i'd keep a spare tank (if using the paintball one), that way you could have one running while going to fill the other one and what not. 
as for the flow control, they fill scuba tanks to 3000psi, then trust the flow controls enough that they let you breath from it. in this case, the output would go to an air bag, not your lungs, so i would trust those controls. 

kevin, your concern is mine as well. i was hoping that some sort of air flow/volume engineer would be able to chime up and give us some numbers. other then that, my only option would be to give it a shot. my setup is manual valves, one line leaving the tank. so it wouldnt be a big deal for me to tap into that line for testing purposes, keeping the conventional setup in place in case i only get one day of use out of it. to me it wouldnt be worth it if i didnt have a couple weeks use out of a tank. my wife drives the car daily.


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## mr sarcastic (Nov 2, 2006)

some good reading right here. i'm gonna do this in the next month or 2.....


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## theAntiRiced (May 7, 2005)

mr sarcastic said:


> i'd keep a spare tank (if using the paintball one), that way you could have one running while going to fill the other one and what not.
> as for the flow control, they fill scuba tanks to 3000psi, then trust the flow controls enough that they let you breath from it. in this case, the output would go to an air bag, not your lungs, so i would trust those controls.


Having a spare would be optimal.

I don't know much about scuba equipment, but a breather isn't a electronically controlled valve, so it's all different stuff.


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## mr sarcastic (Nov 2, 2006)

theAntiRiced said:


> Having a spare would be optimal.
> 
> I don't know much about scuba equipment, but a breather isn't a electronically controlled valve, so it's all different stuff.


My setup isn't an electronic valve, i have manual paddles. but my point is the same. they have flow controls and safety releases on a scuba regulators that are meant to save your life if the tank decides to release all 3000psi in your mouth. Same with paintball stuff, the gun can only handle a few hundred psi. I'd keep those safety regulators and release valves with my setup to protect the valves and bags.


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## mr sarcastic (Nov 2, 2006)

pulling the trigger on this pressure regulator.


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## bassmanjosh (Nov 6, 2004)

Aren't scuba tanks *really* heavy?


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## v-dubIV (Jul 6, 2003)

HHmmm don't have time to click the links right now since i have to leave for work, but this is very interesting, it's cool to see someone thinking outside the box

I've been wanting to do air on my car since it's a daily, and lets face it, you don't always get to travel the nicest roads so i just can't bring myself to slam it static. I've been thinking of doing a set up with 2, 2.5 gallon tanks so that i can set everything up and still keep my spare accessable, my thinking was a compressor for each tank and one tank would control the front and the other the rear, but if something like a paintball gun tank could work that's much smaller

anyway enough of my rambling continue.......


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## mr sarcastic (Nov 2, 2006)

bassmanjosh said:


> Aren't scuba tanks *really* heavy?


Yup, that's why i'm going with the paintball tanks. They're super light.


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## _Dirty_ (Sep 30, 2009)

bassmanjosh said:


> Aren't scuba tanks *really* heavy?


Yes, I picked my buddies tank up from the local scuba shop there other day for him, weighed ~30lbs plus you run the risk of the port popping out and then boom you have a missile.


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## mr sarcastic (Nov 2, 2006)

they design these things (scuba and paintball tanks) safe enough to be carried on your body in "high activity" situations. if a dude can play paintball, rolling around and doing whatever it is that they do, and the port doesnt pop off, i'm sure it'll be fine in the back of my car. 
i too had a hard time grasping the thought of having a 3000 psi tank in the car, but think about it.... people have had them strapped to their backs for years. they're designed to last and have safety systems to prevent them from being a missile.


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## v-dubIV (Jul 6, 2003)

now that i think about it a friend of mine had a tank in the back of his mini truck that looked like a welding gas tank i believe he said was nitrogen filled. the only thing is if you hook up a compressor-less system you can't "play" with it as much since you run the risk of draining you tank and being stuck layed out somewhere


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## mr sarcastic (Nov 2, 2006)

this is true, i think for my situation it'll be fine though. 90% of the adjustment my wife does to the bags are adding 20lbs to the fronts when navigating through the parking garage in the morning. she doesnt always lay it out when parked, then air it up when she leaves. they get the most adjustment when i drive it cause i feel the need to lay frame everytime i park.....


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## firebert (Feb 25, 2008)

lot's of mini truck & low rider guys run nitrogen scuba tanks. Just regulate it down to 150-200PSI when it enters your regular air tank and you're good to go. Add a schader valve or small compressor for emergencies.:thumbup:


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## mr sarcastic (Nov 2, 2006)

i'll definitely have a schader valve in the setup. my tank and compressor setup is completely removable right now, everything is bolted down to a removable bracket. quick disconnect on the air line going to the paddles, same with the power and ground going to the compressor. so i'll leave the connections there in case i need to throw it back in.


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## MechEngg (Jan 13, 2009)

Easy way to figure it out...

PV=RT

Assuming R and T are the same (similar conditions, same fluid) then PV=PV 

I will assume setup 1 is an 80 gallon scuba tank at 3500psi and setup 2 is a 5 gallon tank at 200 psi.

80x3500 = 280,000
5x200 = 1000

Assuming that a 5 gallon tank will get you 1 lift exactly (thats about right depending on your situation) then the scuba tank will be worth essentially ~280 fills with your compressor. Zero fill time is a very nice benefit and if you put that over time of 10 full lifts per day, $5 a fill for the scuba tank, $200 for the compressor, it would take over 3 years to pay off having a compressor. 

So in essence it would be cheaper by quite a bit to run scuba tanks if you want to run your air system for a year or two, but if you plan to have this in the long run i would recommend compressors. 

I haven't taken into consideration costs for time and fuel to actually go to the shop to get the tank filled but each to their own because some people may work at a shop and get stuff for free. I also assumed you had your own tank that you would be using.


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## mr sarcastic (Nov 2, 2006)

is that how they measure the volume of a scuba tank, in gallons?


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## MechEngg (Jan 13, 2009)

mr sarcastic said:


> is that how they measure the volume of a scuba tank, in gallons?


I stand corrected, i used the normalized size rating for a scuba tank. 

The largest tank available is just under 5 gallons of volume, so this would lower the scuba's range to 17.5 lifts which would not be beneficial at all. You would have to fill it a few times a week and would never know when it was getting low.


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## [email protected] (Jan 26, 2006)

This is not thinking out side the box. People have been doing it longer than VW's have been into air.
I will leave you guys alone to figure it out. It makes for good entertainment.


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## mr sarcastic (Nov 2, 2006)

No need to get all elitest about it.


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## bassmanjosh (Nov 6, 2004)

MechEngg said:


> Assuming that a 5 gallon tank will get you 1 lift exactly


My 5 gallon take will get me 2-2.5 lifts.


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## MechEngg (Jan 13, 2009)

bassmanjosh said:


> My 5 gallon take will get me 2-2.5 lifts.


Again it all depends on the type of bags you are running, what management and what size lines. Everything is a factor here.


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## mr sarcastic (Nov 2, 2006)

figuring how many gallons in a high pressure tank is a little more complicated then what's been posted here. do a quick google search. 
quick reference

i'm trying to follow the calculations in this thread but it aint happening right now. 

needless to say the math thats been used so far here isnt relevant.


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## MechEngg (Jan 13, 2009)

mr sarcastic said:


> figuring how many gallons in a high pressure tank is a little more complicated then what's been posted here. do a quick google search.
> quick reference
> 
> i'm trying to follow the calculations in this thread but it aint happening right now.
> ...


No offense but if you can't follow any of that math then how do you figure that my math is irrelevant? They are using the exact same formula as i am, just working in equivalents 

Let me write this out for you a different way, you might understand total volume's better. And now that i have the actual size of tank that they are using it will help too, because for my last calculations i used a 4.75 gallon (size) tank. 

So from here on i will use gallons for the volumes of the tanks and i will measure everything against each other in terms of cubic feet equivalents. I think this may be the part i was unclear about.

So in total you are going to start out with 80ft3 of air in your tank (or 598 gallons of air in your ). You have to subtract the volume of your tank at 145 psi because this will be your lower limit to fill your 5 gallon tank. (this number is 3.86ft3 and is achieved by my previous formula PV=PV) and this is your total useable air that can be transferred to your other tank. Therefore the total volume of air that can be used to transfer to your 5 gallon tank is 76.14ft3.

Now to figure out how long it will last in terms of a 5 gallon tank why don't we just use this scuba tank to fill a 5 gallon air tank and then just keep emptying it from 145 to 115 psi since this is what one of the pressure switches is. 

To fill the tank from 115 to 145psi we need to take a look at the total volume of air that is in the tank at each end point and subtract them. Using the same formula there is 5.2289 ft3 total air in the tank at 115psi and 6.59 ft3 in the tank at 145 psi. Therefore to fill the tank it will take a total of (6.59-5.2289) 1.3611ft3 of air.

So dividing we achieve that we are able to fill up our 5 gallon tank 56 times before they are both at 145 psi. We then have that last little bit of air to account for so we can safely say that a scuba take (80 ft3 equivalent) will be the same as filling our tank up ~55 times.


Now is there anything that you don't understand here? I only used one formula, and you need to remember that atmospheric pressure is 14.7psi and the volumes of the tanks are 2.93 gallons for the scuba tank and 5 gallons for the air tank.

:beer:


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## mr sarcastic (Nov 2, 2006)

haha, now that i'm fully awake i can concentrate and understand the math. very well explained. so, what would be the total amount of full tanks (conventional air ride tank 5 gallon) in a scuba tank, filling it from 0 up to 150psi? i technically get 3 full lifts from my tank, actually 2.5 but that last half isnt possible due to equalization, so would only be relevant for the last half of the lift from a scuba tank also. i want to only use the high pressure tank, so if i know how many total full tanks are in scuba tank, i can times that by 3 and get total lifts.


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## 01 (Sep 9, 2009)

holy fack, this dude has two scuba tanks, 3 regular tanks, and 4 viair 480s 

http://www.lxforums.com/board/f141/40-ft^3-nitrogen-tank-scuba-tank-vs-air-compressor-202155/


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## mr sarcastic (Nov 2, 2006)

i dont understand why people would want their setups to be jerky like that.


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## 01 (Sep 9, 2009)

mr sarcastic said:


> i dont understand why people would want their setups to be jerky like that.


its for show, i hate it as well. 1/4 lines FTW!


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## TurboREX (Aug 7, 2006)

1/2 inch lines ftl


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## gunselman (Apr 6, 2010)

The average compressed air/ nitrogen paintball tank has a preset regulator built into the tank (normally set to 800psi). Most older tanks are 3000psi, newer higher end stuff is 4500psi. So if using a paintball compressed air tank you will need a way to step the pressure down very low. Palmers pursuit shop makes a regulator that will go from 0-1000psi. This could easily step down a paintball tank. 

I would bet that they would have some trouble with the volume that is required though. I would give the guys over at palmers a call and see what they say. 

Scuba tank will be 3000psi as stated. not sure on scuba regulators but i do know that they are completely different than paintball ones.


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## furr (Jul 3, 2009)

mr sarcastic said:


> i dont understand why people would want their setups to be jerky like that.


I don't either..but people like that


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## vdubbinn8611 (Apr 14, 2008)

much force up in the rears that th rear wheels bounce off the ground fo a second... wayy too Jerky and would be hard to adjust slightly as you ride if you wanted too it seems


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