Perfect Set of Tanks Poll

[shurite7]

Neutral buoyancy al80's? I did not realize there were any al80's that did not turn positive when low. Who made/makes them?

Luxfer and Metal Impact make neutral AL80s that are 3300psi. Worthington used to make them as well. They are nice for recreational diving. Their buoyancy when full is -5.86 lbs (Luxfer) and -5 lbs (Metal Impact). When empty their buoyancy is -.9 (Luxfer) and +.1 (Metal Impact). The true capacity of the both tanks at 3300 psi is 77.4 cft.

 

[tbone1004]

Neutral buoyancy al80's? I did not realize there were any al80's that did not turn positive when low. Who made/makes them?

Both Luxfer and Catalina made them. I think Luxfer was S80N and Catalina was C80 maybe? fill pressure was 3300 like the AL100's. Problem is they are the same weight as a standard 80 if you strap some lead to it to make it neutral and it's still a junk tradeoff vs. steel.
Catalina C80 is 25" long and 34.4lbs, holds ~80cf of gas
steel 100's are 24" long, weigh 34lbs, and hold ~100cf of gas
which one are you choosing?

 

[lowviz]

because a rebreather is still close to a $15k investment? There wasn't really any tongue in cheek. I wasn't able to truly justify going CCR until I had reached the limits of LP121's and 2 stages on a scooter with a backup scooter. That's a LONG way in, well for most people, it's a cakewalk for some others, but it's easily a mile back in most caves in Florida. ...//...

Fair enough, excellent analysis.

But you are not the norm. As soon as the going gets rough (compared to peers) the deep pockets go RB. No?

I would suggest that the beginning diver buys tanks that are easily sold. They are popular for a reason...

 

[tbone1004]

Fair enough, excellent analysis.

But you are not the norm. As soon as the going gets rough (compared to peers) the deep pockets go RB. No?

I would suggest that the beginning diver buys tanks that are easily sold. They are popular for a reason...

that's why I put at the bottom of my first post that if I were new/aspiring tech diver, or even recreational diver that I'd get/recommend HP100's or HP120's depending on height, or LP85's if in sidemount. Only need to go to 121's is because it saves a stage bottle over LP85's but by the time you get to that point, you're in pretty deep. Would never recommend them as a first set of tanks.

and on deep pockets going RB, it depends. In cave country it seems to be starting to trend that way recently with a lot of new developments in CCR especially the sidemount ones, but scooters are definitely more practical for extending range and a heckuva lot cheaper

 

[Joebar]

no choice for metric and bar?

 

[EireDiver606]

Even if one can find used Worthington LP85s, I would say they're only preferable to HP 100s if one plans to consistently get fills well over the rated pressure, as is common in cave country. As the poll results seem to suggest at the moment, the HP 100 is a great all-around singles and doubles tank for people of modest stature.

What is a HP100 in metric?

 

[Lorenzoid]

What is a HP100 in metric?

Those would be 15 L tanks, I believe.

 

[tbone1004]

What is a HP100 in metric?

Ours from Faber are 13L and rated to 237 bar. Obviously a bit of wiggle room there. Fabers are 12.9L, Worthingtons were 12.2L so in that general 12-13 ish range

@Lorenzoid 15L's are LP95's or HP 117/119's

 

[211ratsbud]

I calculate roughly 12l @232

 

[EireDiver606]

Ours from Faber are 13L and rated to 237 bar. Obviously a bit of wiggle room there. Fabers are 12.9L, Worthingtons were 12.2L so in that general 12-13 ish range

@Lorenzoid 15L's are LP95's or HP 117/119's

Thanks for the replies @Lorenzoid and @tbone1004 as I was wondering why 15 litre tanks would be common in doubles. Surely they’re not? They would be sooo heavy...

If I was to buy a good common first tank, should I buy a 12 litre @ 232 bar or 300?