Lookie lookie at what i found on craigslist

[captain]

I used one of those for snorkeling. My short gray UDT vest was for scuba! I liked the short length of the UDT vest and the quality was better. I'm not sure but the CO2 cartridge may have been a little bigger?

I used them for years, still have a couple and they are almost indistructable. The CO2 was mostly used for a swimmer struggling on the surface to quickly gain buoyancy, below 50 feet they would not have much lift until reaching about 20 to 30 feet.

The UDT vest has a much larger CO2 cylinder but was only authorised for use above 30feet. A dual cylinder vest is authorized for use to 90 feet but it has an over pressure dump valve. In my avator picture I am using a UDT single cylinder vest with twin Navy 90 cu/ft tanks.

 

[RickI]

I had one of those too, got it for $5.00 at a garage sale. It was as old as me at the time. They used 25 g cartridges. Even with that, though I never fired one at depth too cheap, I wonder if it would bring you up at much speed from 3 ata or so. Got a replacement a few years back for free diving, won't say how much more it cost me either, sigh.

 

[RickI]

Say Captain are those Northhill aluminum 90 cft. tanks you're wearing in the photo?

 

[captain]

Say Captain are those Northhill aluminum 90 cft. tanks you're wearing in the photo?

No, those are 1967 Navy non magnetic tanks specially made for Navy EOD (explosive ordinance disposal). There were no commercially available aluminum tanks at that time, pretty much just steel 72's. One picture is of the Dept. of Defence acceptance stamp

 

[RickI]

Thanks for the photo, they do look similar. When I was 16 I bought a pair of aluminum 90's off a lifeguard who said he used to be in the Teams. The tanks were black, even had UDT frog decals. They weren't available to civilians as you say. Everyone, including myself up to this point were stuck with steel 72's. Being fairly small and good on air, imagine going from 72 cft to 180 cft. in a day?! It was like discovering a new technology. They were made by Northhill out of a solid block of aluminum on a lathe. Do your tanks have a round circle in the bottom? If so, those are the bases of the fluted plugs they patched the lathe attachment hole with. One of mine started leaking while being filled in the Keys. Expanding air bubbles coming out of the base of the tank. About gave the dive shop guy a coronary. I ditched the tanks shortly after.

A closing note on the lifeguard. A nice guy and into hang gliding with the old billow wing gliders. The kind without wing battens, hadn't been invented yet for the open market. He was doing a demonstration static drop from a balloon in 1974. He was released from 5000 ft. but in nose downward in a stall. The old gliders when they entered a stall stayed that way I understand, lacking battens to maintain a foil section. He didn't survive the flight tragically.

No, those are 1967 Navy non magnetic tanks specially made for Navy EOD (explosive ordinance disposal). There were no commercially available aluminum tanks at that time, pretty much just steel 72's. One picture is of the Dept. of Defence acceptance stamp

 

[Nemrod]

I dove with mine for years. it came with my first set of gear. I still have it and it still works. It is not a BC, it is for surface flotation only. Back then divers had to be swimmers, so you only needed it if you got like those mysterious stomach cramps or leg cramps that would somehow immediately suck you down to Davy Jones. N

 

[Papa_Bear]

I still have mine! This is me with the "Horse collar" on in 1973! Not the same model, but close!

We disconnected the CO2 so it didn't go off by accident! LOL and BS we dived with it and puffed air into it and released the puffer valve to let the air out! It was such a pain in the ass I didn't use it much unless I was real deep hunting 80lbs Halibut!

 

[captain]

Thanks for the photo, they do look similar. When I was 16 I bought a pair of aluminum 90's off a lifeguard who said he used to be in the Teams. The tanks were black, even had UDT frog decals. They weren't available to civilians as you say. Everyone, including myself up to this point were stuck with steel 72's. Being fairly small and good on air, imagine going from 72 cft to 180 cft. in a day?! It was like discovering a new technology. They were made by Northhill out of a solid block of aluminum on a lathe. Do your tanks have a round circle in the bottom? If so, those are the bases of the fluted plugs they patched the lathe attachment hole with. One of mine started leaking while being filled in the Keys. Expanding air bubbles coming out of the base of the tank. About gave the dive shop guy a coronary. I ditched the tanks shortly after.

A closing note on the lifeguard. A nice guy and into hang gliding with the old billow wing gliders. The kind without wing battens, hadn't been invented yet for the open market. He was doing a demonstration static drop from a balloon in 1974. He was released from 5000 ft. but in nose downward in a stall. The old gliders when they entered a stall stayed that way I understand, lacking battens to maintain a foil section. He didn't survive the flight tragically.

From what I heard the 90's were made by PST by rolling closed the ends of 6061 aluminum tubing. Being the bottom could not be rolled completely closed the remaining hole was plugged. Early versons have 1/2" pipe thread valves and both ends are completely round with no neck protrusion like the 3/4" valve versions have. I think machining a tank from a sold billet of aluminum would be extremely costly and difficult if even possible.

 

[RickI]

Sounds like I stand corrected, one more myth of youth dissolved. Thank you for the information. Still, they were remarkable tanks back in the day, all that extra capacity. Did some wall dives in the Biminis and Cay Sal Banks with the set and quite a few dives off Ft. Lauderdale before the base plug started leaking.

 

[Splitlip]

I still have mine.

I rigged it with a parachute type harness and used it like a crude BCD. It has an OPV.