Air pistol CO2 Ballast system

**Guest** · 03-12-2005, 03:29 AM

I thought about the air

I thought about the air pistol for my missile launcher, but not for my ballast system. I prefer the air pump for my RCABS for ballast control. I do however use a device for my missile launcher that is similar to the air pistol. It is an Ultraflate Bicycle tire inflator, which uses the small CO2 cylinder. I use a high torque mini servo to activate the trigger. See 2 pictures of the missile launcher on my Homepage

Edited By Art Broder on 1110616604

**subtech** · 03-12-2005, 07:51 AM

Hi Byron,

Mike Shubar sells the

Hi Byron,

Mike Shubar sells the whole setup for a CO2 system. You can contact him at]www.mikessubworks.com[/url] or mike@mikessubworks.com

Dave - SubTech

**bigdave** · 03-12-2005, 07:59 AM

Byron, Check out the Co2

Byron, Check out the Co2 system that Mike Shubar sells at (www.mikessubworks.com). I use it in my Nautilus and it works great. You need a regulator to step down the pressure from over 2000PSI to under 100PSI. Co2 systems are great but must be handeled with care. Ask Jim Butt about the explosion in his Battfish. I get my cylinders filled at a local paint ball shop for only $1. Not Bad! Dave.

**collins class** · 03-12-2005, 11:26 PM

Thanks for the responses.

I

Thanks for the responses.

I had seen Mike's system which is at http://www.mikessubworks.com/co2.html but was not clear that it was using the systems CO2 sources or valve system as the pistols.

I understand the pressure regulation problem a little having been a diver using a 120 cuft 3400 psi high pressure steel cylinder requiring special fittings and converters. Nothing quite so small though.

I found this excellent info on the subject from http://www.pyramydair.com/site/articles/co2/:
[BEGINNING]
CO2 and Pressure
CO2 is a gas at temperatures above -69.9 degrees F and 60.4 psig (pounds per square inch gauge). It is a very complex compound with the ability to sublimate (change directly from a solid to a gas without becoming a liquid) as just one of its unique properties.

At 70 degrees F, CO2 obtains a gas pressure of 852.8 psi when confined in a vessel. If there is more CO2 in the vessel, it will be have to be in liquid form. So, the state of CO2 in a pressure vessel, such as a powerlet at room temperature, is a pressurized gas above a liquid. If the gas is released, such as through the operation of an airgun valve, some of the remaining liquid flashes to gas until the pressure is equalized for that temperature.

It's important to understand that CO2 pressure is determined by temperature, not by mechanical compression. If you were to compress gaseous CO2 by mechanical means, it would turn into liquid when the right pressure was reached. The pressure in a 12-gram powerlet remains constant until all the liquid is gone. A powerlet has the same internal pressure as a 10-oz. bulk CO2 tank when both are at the same temperature. Therefore, CO2 guns do not lose velocity as you shoot them until all the liquid is gone and they start to run out of gas.

Also, keep in mind that CO2 is a refrigerant gas. That means it cools when it expands by flashing from liquid to gas. Therefore, when you shoot a CO2 gun rapidly, the gas will cool the gun parts considerably. Because CO2 pressure is based on temperature, the pressure in a CO2 gun will drop if a series of shots are fired in rapid succession. In practical testing, I've seen velocities decrease by more than 100 f.p.s. over a long string of shots. With a target pistol, I like to allow at least 15 seconds between shots so the gun's temperature can cycle back to where it was before the shot.

DOT regulations require the use of a burst disk in pressure vessels larger than two inches in diameter. The brass nut with the hole in the side contains the burst disk in this bulk CO2 tank. If pressure inside the tank rises above the safety level, the disk ruptures, releasing all the gas inside. That keeps the entire bulk tank from exploding with the force of a bomb.
On a very hot day, CO2 pressure will climb rapidly into the danger region. Where that danger region is, depends on how much liquid is in the pressure vessel. Larger CO2 tanks have pressure-relief devices for safety; so, instead of the whole tank blowing apart like a hand grenade, the burst disk will rupture and exhaust all the gas. When this happens, it's very startling to anyone nearby, and the tank has to be repaired before it will hold CO2 again. Obviously, it's unsafe to leave a CO2 gun or a tank in a closed car on a hot day.[END]

I guess I was just thinking that because you can buy a cheap airpistol it should be possible to canabalise the gas handling system from it and stick it in the sub either as the primary or failsafe ballast system. Wishful thinking I guess

One other thought I had on this subject was maybe using this type of system in a similar vain to Art's but for deploying a rescue location buoy with flashing LED and trailing wire as part of a failsafe sub location system.

If nothing else pursuing this thought has given me a bit of an education on the subject.

Thanks
Byron

**bigdave** · 03-13-2005, 07:29 AM

Hi Byron,
I use a

Hi Byron,
I use a Clippard valve to control the gas in my sub. It is just like a propel system once you step down the pressure with Mikes regulator. You can use the small powerlet type or the larger bottles. I use a Subtech SES-2 to control two Clippard valves. One sends the gas to my ballast tank to force the water out. The other valve works a small pressure cylinder to vent out the air filling the tank. I have been running it six years with no problem. Dave.

**collins class** · 03-13-2005, 11:03 AM

Cool, thanks Dave. Do you

Cool, thanks Dave. Do you have pics posted anywhere of the system?

Hope you are feeling better BTW.

Byron

Air pistol CO2 Ballast system

Air pistol CO2 Ballast system

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