While I understand that I could buy a commercial unit with the tank for around $150.00, I'm living in an area where I cannot get the tank filled. More specifically, I live in a small rural town and it is 50 miles from even the nearest Wal-Mart. There is a place that fills paintball cylinders, but they will not fill larger tanks. SO, after playing with DIY CO2 for a while, I too wanted to upgrade.

I could have bought the Red Sea unit, but what fun would that be!

After looking at the options, I decided to go with a DIY project. The problem that people seem to have when embarking on this DIY project, (the same one I initially had), is that the regulator doesn't hook up to the paintball tank. Well since I did some research, I figured I'd share my findings.....

First off, all these regulators come with CGA threaded fittings. All that means is that the 'Compressed Gas Association' came up with different threads to connect different gas tanks up to the proper regulator. It's all about safety. You wouldn't want someone accidentally hooking up Acetylene (a highly flammable gas), in an application that required inert gas, such as CO2. That being said, high pressure regulators that we need to use in a pressurized CO2 application are basically built the same...whether it's intended for Oxygen, Acetylene, CO2, etc. What changes on these regulators is the threaded end that connects to the tank.

My idea is simple. Probably not the first to do it, but still easy enough that it bears repeating. Remove the CGA threaded fitting! Another thing that these regulators have in common is that they have NPT (National Pipe Thread) threads that screw into the regulator body. Note - I haven't checked every regulator on the market to ensure that every regulator is equipped with NPT threads, but I did look quite a few of them up and it is common enough that I didn't even see one advertised with anything other than NPT. What this means is that your local hardware store has the required parts to finish the job.

Here's a picture of the setup:



Here's a close-up of the required fittings:



The 1/4" Nipple threads directly into the regulator body once the CGA fitting is removed. I didn't take any pictures of the CGA fitting, but just about any picture on the internet will show you what it looked like before. Next, thread the reducer onto the 1/4" nipple. The reducer is required because the Paintball remote came with a 'Quick Disconnect', (the kind on an air compressor only smaller), and the thread is 1/8" NPT. The reducer mates these two sizes together. Finally, thread the quick disconnect from the Paintball remote into the reducer. Make sure everything is tight! Use pipe joint compound if you have it on all the threads. I had some PTFE lying around and used it instead...I'll have to see how that works over time. The compound/PTFE keeps the CO2 from leaking out of the threads.

The medical oxygen regulator that I got is nice because it is already built for low PSI applications on the output side....you wouldn't want 200 PSI blowing up someones nose! A needle valve inline is recommended however, because the pressure we use on our tanks is really low and a little finicky to get dialed in on the regulator.

If you look it up on the internet, you'll also find that the burst pressure ratings of 1/4" galvanized pipe is far from the tank pressure of even a full sized CO2 tank. Somewhere near 3000 PSI for 1". I couldn't find a value for the smaller pipe but 1/4" pipe will have an even higher burst pressure rating than that, and much higher than the tank pressure. So, it is safe!

Breakdown on the cost:

$15.00 for the oxygen regulator on Ebay.
$23.00 for the Painball Remote on Ebay.
$0.96 for the 1/4" to 1/8" reducer
$1.17 for the 1/4" nipple
$24.95 for the Paintball Cylinder
$2.50 to fill it.

Total: $67.58

That's it....just add your favorite reactor/diffusor, needle valve, and check valve and it's ready to go! It's been running now for two weeks without a problem. I figured I'd give it a bit of a test before I posted.

Hey, that's pretty cool! Good work!

How did that CGA fitting come off? Just unscrew? And do you think that would be the case with any oxygen rig?

Also, I don't know anything about gas, but I though CO2 was supposed to be somewhat caustic, or something like that. Are you sure an oxygen rig will work long term with CO2?

Either way though, that's a nice piece of DIY work. Thanks for sharing that!

The CGA fitting just unscrewed...Took a pipe wrench though as it was really tight! The only difference that I've seen in oxygen rigs is that they do make a regulator that looks kind of like a diving regulator. This is so obviously different that I don't think anyone would make that mistake.

Actually, CO2 is corrosive only if mixed with water CO2 + H20 --> H2CO3 (Carbonic Acid). If there is enough moisture in the tank, or internally in the regulator, it can become an issue as well as it is an issue for any regulator or tank. However, this isn't normally a problem with CO2 tanks and why it's a good idea to add the checkvalve and keep the tank from cooling/heating too quickly (condensation). O2 however, is reactive with almost any material which is not fully oxidized. So, actually I think it matters very little, but the O2 regulator should have a longer life with CO2 than O2.

Thanks! I'm glad I could share it...(was actually looking forward to it!)

Hm, wow, looks great. Thanks for the DIY pics. I'm sure someone will be happy this found this thread. =)

Well, since I've been PM'd with a couple of questions on how to make it even cheaper since I may have found my regulator at a bargain basement price, here's an alternative. An absolute low budget yet workable unit could be built out of this:



This valve is rated at 6000psi and cost $12.00 on Ebay. It is 1/4" NPT on both ends and would require only the nipple and reducer on one side to connect to the paintball remote unit and a suitable 1/4" tubing connector on the other side. Disadvantage is that it has no guages, but that isn't a necessity if you check your tank weight often...could be done with a scale and refilled before empty. These aren't always available really cheap, but can be found once in a while for very little.

###EDIT### As per the advice given below by Rex Grigg, you should not use this type of valve without a low pressure regulator/needle valve on the output side. For anyone who doesn't know, an 'End of Tank' dump can occur when using a standard needle valve without a low pressure regulator or secondary needle valve. Although a high pressure valve will certainly limit the amount of CO2 into the tank, even to the desired level, it only does so at the initial pressure. Without the low pressure regulator/needle valve, the high pressure needle valve will continue to dump CO2 into the tank when the pressure starts to decrease in the tank. Since the needle valve is set at the initial pressure of the CO2 tank, it will restrict the pressure to the desired output only at that pressure. The setup will work safely with a low pressure regulator and another low pressure needle valve, but you could probably buy a standard CO2 regulator for the same price or less as the valve + the low pressure regulator.

That valve will cause a end of tank dump in a heart beat. While you might save money up front you have to consider the value of your livestock.

Working with compressed gases is not the place to cut corners.

Your absolutely correct. I forgot about that when writing the post. Using a low pressure regulator would work on the output side, but even though low pressure regulators are cheaper, the cost becomes a consideration when adding that to the price of the valve. Glad you brought that up in the thread!
There are many people trying to get into pressurized CO2 on this thread as well as the others. Seems that cost is always a consideration. To be clear, I would have definately bought a complete full sized system rather than build a paintball system if I was able to get the tank refilled without driving 150 miles!

Since I read that you are a sort of 'guru' on CO2 setups, would you have any advice/cautions/criticism about the system I put together? Other than being impractical when a full sized setup is available at a decent price, it is working quite well for my needs.

If it works for you then it works. But I find it hard to believe that there is no welding shop or fire extinguisher shop or beverage distributor within 150 miles of you.

Well, it is kind of hard to believe. That's what I thought when I first moved here!

To give you an idea of just how remote the area is, here is a picture of my COUNTY's phonebook (Yellow and White Pages):

Note that Ontonagon County is one of the largest counties in Michigan!





And finally a picture of the whole town of Ontonagon, Michigan:



So, there's not many options out there for me....not exactly a booming economy in Michigan's Upper Peninsula. I'm sure there are other's from Michigan on this forum who could attest to just how remote the Keewinaw Peninsula is....way, way remote! There are truly those of us out there who could use an alternative such as the Red Sea Paintball regulator, or my own DIY, because of such limitations. Personally, I think it's kind of fun just to tinker as long as it is done safely.

Well from the looks of the picture there must be at least one bar/tavern and at least one diner there. Ask them where they get their CO2.

I've thought about that, but I've only lived here for a couple of months and I'm still warming up to people in the area. That may be a real possibility in the future, as I'm sure that one of the bars/diners is getting their CO2 from somewhere. I would much rather have a full sized CO2 system and hopefully I'll figure out how to get a tank filled without driving too far. As it is, it's 20 miles to the little hunting/paintball store to get the paintball tank filled.