Should I buy 2x steel HP120 tanks?

[tbone1004]

Almost, I have a pair of Asahi(s) HP120's and a pair of Norris HP120's. Both with 300 bar valves and are nearly identical in height

I forgot Norris made tanks that late. I have a few sets of Norris bottles that are quite nice actually, but forgot they made skinny necks.

 

[kwinter]

If you are talking about PST or Worthington 120s then that is a little bit shorter, but are not longer made new, so you would have to find them used.

I got the impression the OP was talking about used tanks. And when people say HP120, I have to assume they are talking about true HP 3500psi 7/8 skinny neck tanks like PST. The 3442psi/232bar tanks are not the same, but are newer and more plentiful.

And I've had both PST and spun Asahi tanks. The PSTs are a little shorter.


iPhone. iTypo. iApologize.

 

[tbone1004]

oh, I should mention. I own PST HP120's, I LOVE them, but I'm 6'3" with a long torso so I can backmount them with no issues, and sidemount them with no issues.

 

[Bob DBF]

I got the impression the OP was talking about used tanks. And when people say HP120, I have to assume they are talking about true HP 3500psi 7/8 skinny neck tanks like PST. The 3442psi/232bar tanks are not the same, but are newer and more plentiful.

Considering the vast majority of tanks, new and used, advertised and sold as HP are 3442#, hanging on to "true" HP is shoveling s**t against the tide. I now just refer to them as 300 Bar, since that is how they are configured, and reduces confusion for everyone.



Bob

 

[stuartv]

I have 4 HP120s, 2 set up as singles, and 2 rigged as a doubles set. All are the older 3500 psi skinny tank tanks.

I am 6' 1" tall. My 120s are just a little bit too tall for me to sit comfortably on a boat bench while fully rigged up (with crotch strap).

The diving I've been doing with these tanks has mostly been off the Outer Banks, at depths from 70 to 110 feet (roughly). At those depths, I have been consistently diving to my NDL and getting out with 900 - 1200 psi left. I ran the numbers at one point and determined I could have done all my same dives, for the same amount of time, using HP100s, and still gotten out with at least 500 psi. So, no actual benefit to 120s over 100s - yet.

If I were doing dives in the 30 - 50 foot range, I guess I could be using all my air without running out of NDL.

But, for the diving I'm doing, I'd be just as well off with HP100s and be a little bit more comfortable on the surface.

Don't get me wrong. I don't regret the 120s. It is comforting to know I have WAY more gas than I need, most of the time. And I believe I will eventually get around to doing shallower dives where the extra gas might actually come in handy.

Plus, I got all 4 tanks for what I considered to be a steal of a deal. I was actually looking for 100s at the time, but the price was right on the 120s. But, some day, after I win the lottery, I think I'll probably end up with some HP100s, too.

Anyway... just some thoughts for the OP to consider.

 

[victorzamora]

LP85s might be a better solution for you. They're about 2" shorter than the HP120s and hold practically the same gas. They're very commonly doubled up and are also very commonly used as SM tanks. I think they're some of the most flexible tanks on the market.

 

[CptTightPants21]

LP85s might be a better solution for you. They're about 2" shorter than the HP120s and hold practically the same gas. They're very commonly doubled up and are also very commonly used as SM tanks. I think they're some of the most flexible tanks on the market.

Just to be clear, he is talking about a cave filled lp85.

 

[tbone1004]

the new Faber FX100's are basically the same as LP85's in terms of water volume. They hold ~110cf when filled to 3442. No risk of not getting a big fill due to shops not wanting to overfill. If I were in the market for new tanks, this would be the only one I would look at.

 

[CptTightPants21]

the new Faber FX100's hold damn near 120cf when full as well.

~106 at 3442.
~120 at 3900 psi (although I am not sure about overfilling a hp tank--I just don't have the knowledge or experience)

 

[tbone1004]

~109 at 3442

That's close enough. Point was that 85's are often compared to 120's, but they only hold about 110cf. The Faber FX100's hold the same water volume as the 85's but are a bit shorter since they have the bigger OD and will always get you 110cf instead of the 85's which will only get you there if someone over fills them.