build your own power tank

[sportscarfan]

I also use a 20# Co2 tank with a fixed 100psi regulator and a generic 1/4" yellow coily-hose.
Yes, the regulator starts to frost over by the time I'm airing up the 4th tire, but it has never yet frozen up completely. Totally worth the $0 paid for the full tank. Finding the fixed 100psi regulator took some google work but they are available.

My 8yo snapped this on our last adventure

 

[Mauzer]

Check here:
Beer Co2 Regulators - Co2 and Nitrogen Regulators for Draft Beer Systems | BeverageFactory.com

 

[nevada]

why all the effort to run a tank, and then still have to pay someone to refill it?

why not use that same tank, and plumb a compressor to it?

the biggest problem to overcome with OBA is space to mount the tank, since that's already being dealt with, why not add a compressor?

 

[TOY2G]

You're right, my full understanding of compressed gasses is lacking a little bit. I was mainly talking from experience more than as a science professor. I think I may have mis spoken a little bit or I was mis understood. I didn't mean to imply that Co2 is a liquid but it does produce a LOT of moisture that I wouln't want in any air tool. From what I have read it doesn't eally hurt the tires so I wouldn't hesitate to use it in a tire. But you can run an air tool off of a scube tank for a lot longer than 20-30 seconds. A smaller 60 cu/ft dive tank filled to 4500 psi can run any air tool at 90 psi for quite a long time.

As for the round bottom of the tank, most tanks come with boots from the manufacturer. If they don't you can get one from a dive shop for a few bucks.



Yes, Co2 will give a constant pressure till it's empty which in my opinion is the only benifit of it Co2 over compressed air.





I'm not saying that Co2 is a bad option because it's not. My point is that compressed air is more user friendly since there is a guage to show how much air you have left. It is also more readily available at any dive shop. Last, a fill or swap of a Co2 tank is going to run between 15-25 bucks as opposed to a fill on a dive tank is about 5-10 bucks.

CO2 preduce ZERO moisture...none, nata, zilch...it is a dry gas. Also Compressed air cannot work on the trail a 20 gal tank of compressed air will not even fill a single tire. you can use nitrogen or CO2 because it can compress to liquid and remain dry thus allowing you hundreds of times the volume. Not to mention using compressed air can be dangerous around fuel or other flammable liquids.

the simple psychics of compressed air make it useless as a source of air for the trail, unless you only need to air up a small tire a little one time.

 

[RedDragonATL]

I just went with the static 150 psi valve from Poly Performance for the tank, and then I have another adjustable valve I put on the end of the hose that I can dial down to 90 psi if I need to use tools. Works like a charm...just be aware like others have said, using air tools will run through the CO2 QUICKLY! Good luck!

 

[MStudt]

I ran a 10lb tank homemade system in my jeep for years and it was always more then enough. You can use a welding tank regulator if you want something that is adjustable, pretty cheap and easy to find them used. Or, search Google and find ways to build your own. I ran this regulator for tools and had nothing but success. However, I did not use the tank for airing up tires. If you only plan on using it for tools, get a fixed regular.

 

[nevada]

CO2 preduce ZERO moisture...none, nata, zilch...it is a dry gas. Also Compressed air cannot work on the trail a 20 gal tank of compressed air will not even fill a single tire. you can use nitrogen or CO2 because it can compress to liquid and remain dry thus allowing you hundreds of times the volume. Not to mention using compressed air can be dangerous around fuel or other flammable liquids.

the simple psychics of compressed air make it useless as a source of air for the trail, unless you only need to air up a small tire a little one time.

are you sure about that? have you actually tried it?


I would like to think my 88cf tank with 4500 psi would be able to fill a tire easily.

but, ive never tried it, so I don't actually KNOW.

 

[02running]

I just went with the static 150 psi valve from Poly Performance for the tank, and then I have another adjustable valve I put on the end of the hose that I can dial down to 90 psi if I need to use tools. Works like a charm...just be aware like others have said, using air tools will run through the CO2 QUICKLY! Good luck!

any links to an adjustable valve? that sounds like a good route.

 

[SV_Dude]

Also Compressed air cannot work on the trail a 20 gal tank of compressed air will not even fill a single tire.

This boggles my mind. How the heck do you figure that compressed air doesn't work on the trail?

My buddy used to fill his 10 gallon tank to 150 psi from my air compressor. He hook that 10 gallon tank at 150 psi and would fill all four of his 33x12.5x15 tires from 15 to 25 psi on that one tank.

I may not have the best understanding on the properties of co2 but you need to get your facts straight about compressed air.

 

[TOY2G]

This boggles my mind. How the heck do you figure that compressed air doesn't work on the trail?

My buddy used to fill his 10 gallon tank to 150 psi from my air compressor. He hook that 10 gallon tank at 150 psi and would fill all four of his 33x12.5x15 tires from 15 to 25 psi on that one tank.

I may not have the best understanding on the properties of co2 but you need to get your facts straight about compressed air.

This fight has been fought before, you are talking 10PSI per tire @25psi max volume. you are only using 8.6 gal of air @ 35psi. use the same tank to fill the same tire after a bead rolls off the rim. you will need roughly 18gal of air at 120PSI and that does not account for setting the bead.

So if you are going to air down and want to carry a 10 gal air tank (more than twice the size of a 10lbs CO2 tank, and you know for sure you will only need to add 10lbs per tire; you could use an air tank. BUT AGAIN, its not ideal for actual wheeling gear..

This was not a fight BTW you just think your way is better and mathematically and scientifically it is not, I was only trying to help.

PLEASE Read from another post on the CK5 forums. it should clear up the how inferior Air is to CO2, not to mention how much more safe and dry CO2 is.


______________________________________________________________________________________________________________________________________________________________________________________________________

Lets find the area inside that tire:

I am assuming we'll subtract 1" from each side for the rubber material so we have a inner diameter of 31" and a width of 10.5". Area of a circle is pi x radius squared so

15.50^2 x 3.14 = 725.47 - > Volume of a cylinder = area of the circle x length so -> 725.47 x 10.5 = 7617.39

Now lets subtract the volume of the rim. Hard to get it exact so lets assume a diameter of 14" because it does not fill the 15". Using same formulas ->

Area = 7^2 x3.14 = 153.86 Volume -> 153.86 x 10.5 = 1615.53

Okay now we want volume of tire - volume of rim =-> 7617.39 - 1615.53 = 6001.86ci lets call it 6000ci

Now, gallons of air depends on pressure but lets go with somewhat standar -> 35psi.

The formula for the volume of a compressed gas is
pa Va = pc Vc (1)
where
pa = atmospheric (STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure) pressure (14.7 psi, 101.325 kPa)
Va = volume of the gas at atmospheric (STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure) pressure (cubic feet, cubic meter)
pc = compressed pressure (psi, kPa)
Vc = volume of the gas at compressed pressure (cubic feet, cubic meter)


Cubic inches to cubic feet = 1ci = 0.0005787cf

Cubic feet to gallons = 1cf = 7.48gal


Now 6000ci = 3.47cf


so formula above using 35psi


Va = pc Vc / pa


Va = 35 x 3.47 / 14.7 = 8.26cf


Converting to gallons 8.26 x 7.48 = 61.8gallons of air.


SO 61.8gal of compressed air.


Now, if you are asking because you want an air tank for desert side inflation or something, you tires hold roughly the size of your tire at same PSI so something like 3.47cf x 7.48gal/cf = 25.955 = 26gal


So air tank ar 35psi must be 26gal to fill the tire to 35psi. Air tank at say 175psi will be much smaller. I think you could just factor it down 35/175 x 26 = 5.2gal but I haven't worked through it yet. To fill 4 tire would require like a 20 gallon tank. Much easier to bring a small CO2 cylinder along that hod 2800psi because it will fill all your tires no problem.

 

[SV_Dude]

This fight has been fought before, you are talking 10PSI per tire @25psi max volume. you are only using 8.6 gal of air @ 35psi. use the same tank to fill the same tire after a bead rolls off the rim. you will need roughly 18gal of air at 120PSI and that does not account for setting the bead.

So if you are going to air down and want to carry a 10 gal air tank (more than twice the size of a 10lbs CO2 tank, and you know for sure you will only need to add 10lbs per tire; you could use an air tank. BUT AGAIN, its not ideal for actual wheeling gear..

This was not a fight BTW you just think your way is better and mathematically and scientifically it is not, I was only trying to help.

PLEASE Read from another post on the CK5 forums. it should clear up the how inferior Air is to CO2, not to mention how much more safe and dry CO2 is.


______________________________________________________________________________________________________________________________________________________________________________________________________

Lets find the area inside that tire:

I am assuming we'll subtract 1" from each side for the rubber material so we have a inner diameter of 31" and a width of 10.5". Area of a circle is pi x radius squared so

15.50^2 x 3.14 = 725.47 - > Volume of a cylinder = area of the circle x length so -> 725.47 x 10.5 = 7617.39

Now lets subtract the volume of the rim. Hard to get it exact so lets assume a diameter of 14" because it does not fill the 15". Using same formulas ->

Area = 7^2 x3.14 = 153.86 Volume -> 153.86 x 10.5 = 1615.53

Okay now we want volume of tire - volume of rim =-> 7617.39 - 1615.53 = 6001.86ci lets call it 6000ci

Now, gallons of air depends on pressure but lets go with somewhat standar -> 35psi.

The formula for the volume of a compressed gas is
pa Va = pc Vc (1)
where
pa = atmospheric (STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure) pressure (14.7 psi, 101.325 kPa)
Va = volume of the gas at atmospheric (STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure) pressure (cubic feet, cubic meter)
pc = compressed pressure (psi, kPa)
Vc = volume of the gas at compressed pressure (cubic feet, cubic meter)


Cubic inches to cubic feet = 1ci = 0.0005787cf

Cubic feet to gallons = 1cf = 7.48gal


Now 6000ci = 3.47cf


so formula above using 35psi


Va = pc Vc / pa


Va = 35 x 3.47 / 14.7 = 8.26cf


Converting to gallons 8.26 x 7.48 = 61.8gallons of air.


SO 61.8gal of compressed air.


Now, if you are asking because you want an air tank for desert side inflation or something, you tires hold roughly the size of your tire at same PSI so something like 3.47cf x 7.48gal/cf = 25.955 = 26gal


So air tank ar 35psi must be 26gal to fill the tire to 35psi. Air tank at say 175psi will be much smaller. I think you could just factor it down 35/175 x 26 = 5.2gal but I haven't worked through it yet. To fill 4 tire would require like a 20 gallon tank. Much easier to bring a small CO2 cylinder along that hod 2800psi because it will fill all your tires no problem.

So you're saying that a Co2 tank that is at about 1800 psi is better than a 20 gallon compressed air tank at 175 psi? No duh! And no, I'm not fighting nor even trying to engage in any form of a heated argument. I'm just arguing my point based on a little bit of research over the last couple days (thanks to you ) and a little bit of experience dealing with dive tanks and co2 tanks.

Let's have more of an equal comparison.

A 10 lb Co2 tank has about 87 cubic feet of usable air stiffed into it. The size of a 10lb Co2 tank is about 7"x25" (per powertanks site). These Co2 tanks are measured by weight but they are filled to about 1800 psi.

A Scuba tank that is roughly the same size as the 10lb Co2 tank is an 80 cubic foot tank. They measure about 7.25"x26". These dive tanks are filled to about 3000 psi.

So now that we have the size of the tanks clear, we know that the size of the tanks aren't that much difference. Yes, Co2 does compress down a little bit more than air but very little. For the same size tank you get an extra 7 cubic feet of usable air. Big deal.

As far as performance of each tank, I wouldn't hesitate to use either Co2 or compressed air for filling a tire or running air tools. I don't think any one has any real world advantage for our uses.

Show me something that says a scuba tank is dangerous. I have yet to see anything that says one is safer than the other for vehicle use. As long as both tanks are mounted firmly and in good shape there is no danger.

My main point here is that there isn't any huge benefits of co2 over compressed air or compressed air over co2 other than the fact that you can get a dive tank filled at any dive shop for a few bucks. A dive tank will last just as long as a comparable size co2 tank but at a fraction of the cost. Filling a 10lb co2 tank is about $15-$20 bucks. You can also have a gauge on a dive tank regulator to show you exactly how much air you have left so you aren't having to guess. Dive shops are all over the place and are usually pretty friendly to fill a tank for you without being a certified diver.

Sources:
Co2
http://wiki.answers.com/Q/How_many_cubic_feet_in_1_pound_of_CO2#slide1
http://powertank.com/products/sfID1/13/productID/76
Scuba Tanks
http://scuba.about.com/od/equipment...ce-Between-Steel-And-Aluminum-Scuba-Tanks.htm

 

[TOY2G]

So you're saying that a Co2 tank that is at about 1800 psi is better than a 20 gallon compressed air tank at 175 psi? No duh! And no, I'm not fighting nor even trying to engage in any form of a heated argument. I'm just arguing my point based on a little bit of research over the last couple days (thanks to you ) and a little bit of experience dealing with dive tanks and co2 tanks.

Let's have more of an equal comparison.

A 10 lb Co2 tank has about 87 cubic feet of usable air stiffed into it. The size of a 10lb Co2 tank is about 7"x25" (per powertanks site). These Co2 tanks are measured by weight but they are filled to about 1800 psi.

A Scuba tank that is roughly the same size as the 10lb Co2 tank is an 80 cubic foot tank. They measure about 7.25"x26". These dive tanks are filled to about 3000 psi.

So now that we have the size of the tanks clear, we know that the size of the tanks aren't that much difference. Yes, Co2 does compress down a little bit more than air but very little. For the same size tank you get an extra 7 cubic feet of usable air. Big deal.

As far as performance of each tank, I wouldn't hesitate to use either Co2 or compressed air for filling a tire or running air tools. I don't think any one has any real world advantage for our uses.

Show me something that says a scuba tank is dangerous. I have yet to see anything that says one is safer than the other for vehicle use. As long as both tanks are mounted firmly and in good shape there is no danger.

My main point here is that there isn't any huge benefits of co2 over compressed air or compressed air over co2 other than the fact that you can get a dive tank filled at any dive shop for a few bucks. A dive tank will last just as long as a comparable size co2 tank but at a fraction of the cost. Filling a 10lb co2 tank is about $15-$20 bucks.

Sources:
Co2
How many cubic feet in 1 pound of CO2
POWERTANK - CO2 Air Systems
Scuba Tanks
Steel and Aluminum Scuba Diving Tanks - What Is the Difference Between Steel and Aluminum Scuba Tanks?

Okay,

i concede that you can use a scuba tank for on-board air. However keep in mind that Dive shops that fill scuba tanks are not abundant, in fact to get my scuba tanks filled i had to drive to Southlake TX (35min). Now that i live in OH, i have no idea where i would get the tanks filled.

Some would argue that there is more danger in keeping a 3000psi tank in your vehicle compared to one under 2000psi, however the catastrophic damage that may result in a car accident or rollover, I doubt the 2000psi will be less damaging. HOWEVER in the event of a car crash and heaven forbid flames and or fuel...A ruptured air tank can cause a massive amount of damaged as fuel for a fire, where a CO2 (inert gas) would be of little concern.

All that said, if you have used and have luck with scuba tanks as your on-board air that is great. My first CO2 tank was a fire fighter SCOTT pack (free) that I had converted for CO2. it was heavy but a super cheap setup. But the question was never about the tank, its about the contents and CO2 is safer and can be filled at any paint ball supply.

Please note: an aluminum CO2 tank can be purchased new from a couple different beer brew companies for under $75, the regulators from TRDParts4U are about $50 and the ARB Hose and air chuck are about $35. just over $150 for a CO2 system is not bad.

 

[SV_Dude]

Okay,

i concede that you can use a scuba tank for on-board air. However keep in mind that Dive shops that fill scuba tanks are not abundant, in fact to get my scuba tanks filled i had to drive to Southlake TX (35min). Now that i live in OH, i have no idea where i would get the tanks filled.

Some would argue that there is more danger in keeping a 3000psi tank in your vehicle compared to one under 2000psi, however the catastrophic damage that may result in a car accident or rollover, I doubt the 2000psi will be less damaging. HOWEVER in the event of a car crash and heaven forbid flames and or fuel...A ruptured air tank can cause a massive amount of damaged as fuel for a fire, where a CO2 (inert gas) would be of little concern.

All that said, if you have used and have luck with scuba tanks as your on-board air that is great. My first CO2 tank was a fire fighter SCOTT pack (free) that I had converted for CO2. it was heavy but a super cheap setup. But the question was never about the tank, its about the contents and CO2 is safer and can be filled at any paint ball supply.

Please note: an aluminum CO2 tank can be purchased new from a couple different beer brew companies for under $75, the regulators from TRDParts4U are about $50 and the ARB Hose and air chuck are about $35. just over $150 for a CO2 system is not bad.

I guess depending on your location a dive shop may be hard to find. Believe it or not, even here in Colorado Springs there are a couple dive shops within a 20 minute drive or so.

I personally haven't ever used a dive tank to fill tires but I have used Co2. It worked great and I had no beefs with it other than I couldn't tell how much air I had unless I took the tank off of the mount and used my calibrated arm to determine the weight of the tank. I have a handful of friends in southern california who I used to dive with who run a separate regulator setup for their dive tanks to run air tools or inflate tires and they have no issues.

 

[nevada]

Okay,

i concede that you can use a scuba tank for on-board air. However keep in mind that Dive shops that fill scuba tanks are not abundant, in fact to get my scuba tanks filled i had to drive to Southlake TX (35min). Now that i live in OH, i have no idea where i would get the tanks filled.

doesn't have to be a dive shop. check for a place that services fire trucks/equipment.

 

[MStudt]

any links to an adjustable valve? that sounds like a good route.

Getting a welding regulator from Harbor Freight if you want to keep it on the cheap. Look for used welding regulators on eBay and Craigslist. That is by far the cheapest route for an adjustable regulator. Keep in mind, I never had an adjustable in the few years I ran a tank on my YJ. If your only using it for tools then a static regulator will work just fine.

 

[02running]

Getting a welding regulator from Harbor Freight if you want to keep it on the cheap. Look for used welding regulators on eBay and Craigslist. That is by far the cheapest route for an adjustable regulator. Keep in mind, I never had an adjustable in the few years I ran a tank on my YJ. If your only using it for tools then a static regulator will work just fine.

i want to fill tires and run air tools

 

[MStudt]

i want to fill tires and run air tools

Welding regulator, cheap, and everywhere.

 

[02running]

Welding regulator, cheap, and everywhere.

is it inline?

 

[MStudt]

is it inline?

Yes, you'll just need to change out the end fitting. They don't come with a quick connect fitting, just a barbed fitting. Change out the fitting and you're good to go. Make sure you check the flow rate for the regulator you get. Some welding regulators have a low flow rate. You might check into a regulator they use for filling balloons, as they usually have a higher flow rate.