Non magnetic steel tanks?

[Whitrzac]

NVM, old navy aluminum tanks.

 

[Scared Silly]

AKA Aluminum tanks - can no longer be re-qualified. Can still be tested but not stamped.

 

[captain]

I have a set, they were made using 6061 aluminum tube spun closed at both ends. The bottoms have a screwed in plug that is ground flush on the out side. All the test information needed is stamped on them. I had mine hydroed but not stamped and fill them myself.

nd fill them myself.amped

 

[Akimbo]

I have a set, they were made using 6061 aluminum tube spun closed at both ends. The bottoms have a screwed in plug that is ground flush on the out side. All the test information needed is stamped on them. I had mine hydroed but not stamped and fill them myself.


View attachment 666164nd fill them myself.amped

I was about 14 years old when I first saw a "Navy 90". The Northern California Chapter of UPS (Underwater Photographic Society) chartered The Emerald liveaboard out of Santa Barbara. Al Giddings had one and got everyone's attention by saying "watch this" and tossing it overboard. To our amazement, it floated! This was about 8 years before Aluminum 80s were introduced in the US. The only tanks in the US market in the mid 1960s were steel 72s and 50s.

Glen Miller (the Captain) didn't blink an eye filling it but he was famous for not sweating much of anything. I have no idea how Giddings acquired it but could fill it since he owned the Bamboo Reef dive shop in San Francisco.

We used double 90s in Navy Scuba school in 1970 but used steel 72s after that, mostly for lobster dives. They were made because EOD (Explosive Ordinance Disposal) divers required all non-magnetic gear.

 

[captain]

The ones I have have a couple of dive shop hydro stamps with various symbols between the month and year from before the RIN became law. I recall a local dive shop filling them in the 70's. I think when AL 80's came out the Navy EOD just switched to them and rebreathers. There were reports of the bottom plugs developing leaks.