Why don't they make an HP tank same size as a 72?

[Eric Sedletzky]

I really like the size of my old steel 72's - 6.9" diameter and long.
Why doesn't somebody make an HP tank similar in outside measurements in an HP version?
Those tanks were about perfect in every way except sometimes I wish they had A little more air.
Or is there such a tank that I don't know about?
What would the volume be if a steel 72 was pumped up to 3442? Provided the tank was built for it - thicker walls, better alloy, etc.
I don't like those short stubby little 7.25" diameter E7 80's

 

[MaxBottomtime]

Merry loves her 100s. They're a little fatter at 7 1/4" but can be filled to 3442 psi.
Scuba Cylinder Specification Chart from Huron Scuba, Ann Arbor Michigan

 

[kwinter]

Maybe its like the Princess and the Pea, but I couldn't tell the difference between a 6.9" tank and a 7.25" tank while diving it, even sidemount. The difference between a 7.25 and a 8.5 is much bigger. I guess my bigger question would be why the manufacturers of modern aluminum 72s decided to make them 6.9" instead of sticking with 7.25. And PST did make a medium pressure (MP) steel 72, 3300psi tank with 6.9" diameter.

As for your other question, a LP72 marked at 2400 with a + rating so that it would be 72cf at 2640 would hold 94 cf at 3442.

 

[Aquavelvet]

I think what you're looking for are the Faber LP 85s. Externally they are very similar to Alu 72s, and trim nicely for sidemount. They're safe to overfill, and can hold as much gas as an HP 100.


Sent from my iPad using Tapatalk

 

[Diver0001]

I really like the size of my old steel 72's - 6.9" diameter and long.
Why doesn't somebody make an HP tank similar in outside measurements in an HP version?
Those tanks were about perfect in every way except sometimes I wish they had A little more air.
Or is there such a tank that I don't know about?
What would the volume be if a steel 72 was pumped up to 3442? Provided the tank was built for it - thicker walls, better alloy, etc.
I don't like those short stubby little 7.25" diameter E7 80's

We have these in Europe. The working pressure is 300 bar and they're ridiculously negative in a twin config.

R..

 

[danvolker]

Except the old steel 72's were almost neutral when full....no BC was needed, even with twin sets.
I am guessing that if the old 72's were thick enough to be filled daily to 3500 psi , then they would be a lot more negative....and what was good would be ruined.

 

[tbone1004]

lp85's are nowhere close to 72's, much too long, hence being lp85's instead of 72's. The PST HP100's and Faber FX-100's are the closest you're going to get, same tank factor, essentially same height, just 7.25 instead of 6.9. Never going to get them to be truly neutral, but the PST e7's are only -1, and the Fabers closer to neutral than that. Just ignore Worthingtons since theirs sink like bricks

 

[oldschoolto]

I'll be the one to say it... Those old steel 72's can take 3200 PSI... All day long... Now , I don't do it... But, I do know people with their own compressors do..

Jim..

 

[danvolker]

When I started my deep diving( 200 to 280 ft) in the early nineties, I used double 72's filled to 3000.... Obviously I never had a problem, but that is not proof for anyone else.

 

[tbone1004]

I fill mine to 3 grand regularly, no problems