I am a fool for spending money on tanks

[Rollin Bonz]

If I understand your point, this is primarily for a diver’s 100th dive?

 

[John C. Ratliff]

Okay, a couple of points:

--The original Scuba tanks were 1800 psig CO2 fire extinguisher bottles, converted for a scuba valve (1/2 inch tapered threads).

--the red fire extinguisher bottle this guy used wasprobably an ABC. Dry Chemical fire extinguisher bottle. He mentioned nothing about purging it of the dry chemical powder.

--As one of you mentioned, this guy has no knowledge of the bottle rating system, and the pressure rating of this bottle. It will probably explode before getting to 2000 psig.

--the regulator's first stage was removed, so it will leak at somewhere just over 200 psig.

--I counted 12 breaths off this Jerry-rigged system; it's doubtful that he spent 7 minutes underwater with it.

--There could be long-term health effects from breathing the residual dry chemical.

SeaRat

 

[almostDIR]

Surplus airforce 02 bottles were also used in the early days of scuba.

I am not familiar with US fire extinguishers but if its a similar abc powder extinguisher they sell here (a 1kg or 2kg model perhaps?) it will definitely explode if pumped to over 120 bars.

Another thing which worries me is that the guy does not seem to know how to properly make threads and the pressure meter will thus probably blow to his face even if the tank would hold the 2000psi.

His idea was maybe to control the flow with the needle valve so that it would act as a very crude 1st stage. Pretty challenging to do correctly and the needle valves are probably not rated for 2000psi either

 

[happy-diver]

I used to make ponys/stages from old fire extinguishers not so long ago

Because, as the kid rides the skateboard along the retaining wall
the adult is uncontrollably compelled to spout force gravitational

 

[almostDIR]

I don't have any 2kg powder fire extinguishers at hand but I have a 6kg one here (the most standard size and type used here) .

I would think twice before putting 2000psi into that one

if the guy on the video is using a CO2 model then the tank could very well hold the 2000psi pressure but these cartridge pressurised powder models would be pretty interesting at that point I think

anyway, I am still sure that his pressure meter will blow out of its threads at the 2000psi pressure and probably right to his face when he is looking at it. We should really get that guy a super slow mo camera so that the project will at least have more entertainment value

 

[John C. Ratliff]

When I was in the U.S. Air Force, we had jump tanks for our Pararescue duties. You can see them in this photo below. These were originally 20-man CO2 life raft bottles, which were converted for scuba diving. They are rated to 2100 psig. I still have a pair of these tanks, although they take a 1/2 inch tapered thread manifold, and so are much harder to get the yearly inspection done on them.

These tanks were originally wire-wrapped, and that wire had to be cut off in order to convert the tanks. The neck then had to be tapped for 1/2 inch tapered threads for use with the then-standard U.S. Divers Company twin manifold.

These tanks were a real pain to convert, but once converted made great scuba tanks. They were narrow, and so swimming with them was easy. They also were slightly buoyant in sea water.

 

[maj2]

Even if the fire extinguisher could handle the 2000psi pressure he was talking about, I would love to see him try doing that with his bicycle hand pump...

 

[kmarks]

Over engineered... who needs a regulator

View attachment 502416

He's gonna feel pretty silly when he gets underwater and realizes he didn't connect his hose to his tank valve.