CO2 setup

[fung pang]

find some thing new in a big blue box home center, a new Co2 air system,
not cheap but after remove the cover and change some fittings, it could be use in a big 1/32/, 1/48 rc sub.

it may have other use in BB gun battleship!

http://www.lowes.com/lowes/lkn?action=p ... J-6901-100


or Item #: 166441 Model: J-6901-100


Mr Jim Butt do you think it is save for us to use it in side the rc sub?

[wingtip]

when i first started tinkering

when i first started tinkering with subs i went the co2 route and bought a bunch of paintball equipment, valves, bottles etc... talked to the paintball shop owner a while and felt they were safe enough so i had him fill two bottles so i could test my theory etc... he said just dont over fill them, dont keep them in sunlight or around anything warm... i said i live 20 miles away will it be ok in the back floorboard wrapped in a blanket in a air conditioned truck... he said sure...
halfway home doing 60 mph i had the living shit scared out of me when one blew the safety valve... after stopping and confirming no major damage to the truck i got back on the road and came home..
pulled the other bottle out and hooked it up to my stuff and did some testing for about 45 min or so and unhooked it all, wrapped it in towel and set it in the closet... this is a nice cooool central air home... 20 min later while sitting at my desk 8 feet away that bottle blew and sprayed co2 all over my clothes hanging above it...
it was at that point i said screw co2 its to dangerous...... rcabs is the way to go unless you just have to have bubbles, then a lower pressure gas system is the way to go .....

[petn7]

I don't see why one

I don't see why one can't just use a 12 gram CO2 cartridge system. Those 12 gram cartridges are pretty safe, small, and it shouldn't be hard to have a regulator, right?

A 12 gram CO2 system would be ideal, for me. I think it would pretty safe (at least as safe as a Propel gas system) as long as one didn't carry a "hot" cartridge in the WTC during transport.

[bigdave]

I have used CO2 in

I have used CO2 in my Disney Nautilus for 10 years now.
I have the regulator from Mike's Subworks and a paint ball type cylinder.
The CO2 works the blow and the vent as well with twin clippard valves and a clippard mini piston.
Jim Butt has run CO2 in his Batfish sense the beginning of recorded time!! BD.

[scott t]

How many ballast tank blows

How many ballast tank blows does a CO2 bottle give?
Can it be partaily filled?
Does it have to be emptied or can it be stored?
Possible topic for regatta lecture.

edit:
Could a co2 pellet hand gun mechanism be canabalized to
fit in a submarine?
Probably still need a regulator.
Might use the mechanism to fire torpedoes.

-Scott

[bigdave]

That will depend on the

That will depend on the size of your ballast tank and CO2 bottle. I have a smaller 4 OZ bottle and the tank is about 4"x 6". I have never really counted the blows, but I use gas on vent and blow.
I have never run out of CO2 I can tell you that.
Maybe Jim knows?
His system is much bigger in volume.
You can store the tanks full or empty. Just not in a hot environment. I get them filled at a local paintball store. $1 is all I pay. BD.

[subdude]

CO2 and you.

Hi kids. Okay, here's the short scoop on CO2.

First and formost, let me tell you that CO2 can KILL YOU if you're not 100 percent following the safety rules and regs. Never, ever play with CO2 without understanding what's going on with it.

Let's start with the good news. CO2 has an excellent expansion rate, giving many blows of a ballast tank from one fill. This, of course, depends on the size of the ballast tank and the size of the supply bottle. Both must be carefully sized. In my 1/48 fleet boat (and yes, BD, it does seem like I've been running the old girl since dinos roamed the earth) I have a 6 oz supply bottle. The ballast tank required to lift her to waterline is 4" diameter, and 11 inches long, giving a volume of 106 cubic inches, and bouyancy to lift some 3.8 pounds. For a tank this size, CO2 works quite well, and is inexpensive to use if you run the sub frequently. I've never actually counted, but I can blow the tank probably 20 - 25 times on a full bottle.

Okay, now the bad news. CO2 stores liquid at 850 psi. No, that's not a typo. 850 psi. Ever seen a truck tire explode on the highway, throwing pieces of tire shrapnel 100 ft in the air? That's what 150 psi will do. Now imagine 850 psi going off. So, each and every componant MUST be safe to use at those pressures, until you get past the regulator which takes the pressure down to "safer" levels. First, the tank must be CO2 approved, hydro tested regularly, and MUST have a safety valve (burst disk) on the main valve. (that's what you guys heard going off. It's job is to "pop" if the pressure in the bottle gets too high, endangering it. It's the engineered in "weak link".)

The supply bottle must never be overfilled, it needs to have room above the liquid CO2 to allow it to expand when it warms up. CO2 gets very cold when expanding or transfering, so 20 minutes after filling the bottle, the internal pressure WILL rise. Again, you need to know what you're doing, and safety first!

After the supply bottle comes a regulator, again approved for CO2. Fittings and tubing must be sized correctly. I have 2 regulators in Batfish. The first takes the pressure to 100 psi. The second is adjustable, and I keep it set at about 35 psi for a nice, steady blow.

All the above componants have some costs involved. They're much more expensive than a schrader valve and a soldered up propel tank. But, propel costs 12 bucks a can, I get my 20 lb converted fire extinguisher "supply station" refilled for about the same cost. Lasts me several years of running.

Here's a pic of Batfish. Notice the DOT stampings on the supply bottle, indicating that's it's been tested. The primary regulator is beneath the bottle, out of sight. The second regulator is sticking up with the adjustment knob visible, From there it is plumbed to a solenoid valve, then to the ballast tank.




There's lots more to know, but that's the basics.

Oh, the 12 gram bottles could be used, but would be VERY expensive in the long run. And the bigger system that started this thread has a tank that's way too large for subs, and it's steel besides. I use an aluminum tank, and brass valves so water exposure won't hurt it.

Hope this helps clear any confusion!

Jim

[petn7]

Great post!

It's good to know

Great post!

It's good to know 12 gram CO2 will work, with the biggest drawback being cost...like I care about cost...

[scott t]

I agree great information.

Thanks,
-Scott

I agree great information.

Thanks,
-Scott

[hakkikt]

A friend of mine had

A friend of mine had a CO2 fertilisation system for her aquarium (for water plants). It worked with quite small bottles, maybe 0.2 litres. When one was empty, she would take it to the dealer to exchange it for a refilled one.

A similar system is used for bars etc. where CO2 is used to push beer from barrels through a tap. When the bottle is empty, they dont go to refill it themselves, they just exchange the empty bottle for a full one and pay only for the CO2 and some small fee. Those are very big bottles of course.

Sounds like this would reduce the danger of overfilling and handling all that stuff yourself in a model sub.

[raalst]

so, as far as I

so, as far as I read Jim's post,
what we, the people, need is a black box which takes
CO2 and dispenses it at about 35 psi.
The rest is safe to add ourselves.
This black box should be "no servicable parts inside".

for all other options you should have an engineering degree, I guess, or a very good liability insurance.

Still, even if there would be such a black box, it would have a break disk (the engineered weak spot jim talks about). If that safety blows,
and it is inside your hull, then the glass hull still makes for a nice
shrapnel bomb. Right Jim ?

It really gives me the willies.

btw, Jim, if you use your system, doesn't the regulator produce a lump of ice and freeze up ? this is a risk in scuba equipment (which I am more familiar with).

oh yes, if you want high pressure black boxes, then maybe this is worth
exploring as well (there are a few brands which deliver the same functionality) :

http://www.spareair.com/product/models.htm

[bigdave]

This is the system I

This is the system I use. It has been trouble free. But as Jim says you must treat the CO2 with respect. BD

http://www.mikessubworks.com/page1.html

[mike dory]

Guy's - THe only thing

Guy's - THe only thing that I can add to Jim's outstanding posting on safety with CO2 is, when filling your small bottle from your supply tank YOU NEED TO WEIGH THE TANK BEING FILLED. That is how you know it isn't being over filled. In Mylo's original posting, he was looking for away to fill on board mounted, CO2 tanks from outside the boat This would mean there would not be away to weight the tanks (unless you could weight the entire boat, which at 1/25 scale might not be to practical) nor could the bottles be easly tested as Jim mentioned

Jim, Who was it that brought there tool box to the regatta that had a CO2 bottle which had exploded inside. It was sight to see. I'm having a senior monent, can't think who that was Jim, you know of course, We could use an artcile in The Sub Committee Report on this subject, hint hint.

[bigdave]

Hi Mike,
Jim may correct

Hi Mike,
Jim may correct me on this but I think it was Gene Burger our old editor. That was a few years back. BD.

[mike dory]

Jim - I think your

Jim - I think your right, Gene had that big 1/32 scale 32 P. Gato class fleet boat as I recall. What an outstanding boat that was... That entire boat ran on CO2. I remenber having a torpedoe fight with him in North Lake... Great times... I can't help but wonder what ever happend to him and his boat? ..I haven't seen him in (must be at least 12 years ago) Well, need to run You all have a great day.... Mike Dory