120's??

[terrasmak]

To heavy , and of course way to easy to get in trouble (NDL) with . I'm slowly swapping my tanks to HP100's , they arnt much heavier, more negitive (good for drysuit) and the extra gas can be nice.

 

[jpcpat]

At deep depths, I hit my NDL before I run out of gas. At shallow to moderate depths I can easily get an hour out of an al 80. After that, I need a cigarette.

a 120 might work for a weekend working with students, but it's so heavy

 

[robbcayman]

Actually when you double the size of the tank you increase by 100%, not 50%.

I can, and do regularly, exceed the NDL's on an AL80. But when my dive buddies all purchased 120's even with the better SAC, I was the "weak link".

Rather than spend the cash on the HP120 I went the dual tank route and now I dive twin AL63's for deep deco dives. But I will be getting into wreck penetration soon and I'll need a redundant air supply anyway.

Doh!!! I wasn't thinking straight LOL!!! Thanks

 

[TSandM]

I have to laugh at myself.

I started to write that 120s or 130s are beastly heavy, and I can reach NDLs at any depth I'm willing to go to on an LP 95; and on multi-level dives, I can stay in the water until I'm thoroughly cold or really need to pee. So why would I carry more gas at the cost of adding 15 pounds to the already onerous amount I carry around to begin with?

Then I looked at the doubled 85s sitting in the corner . . .

 

[Tigerman]

so if i have a tank that is 8,02 inches in diameter, filling preassure 3442 psi and fit 915 cu.in of water, is that a 120 tank? and is it a HP or LP if so?
Im all metric here and really cant find a good site that would tell me what my 15L 232(237) tank would be referred to in imperial measures..
My GUESS would be that it was a (HP?)120?

 

[Drewski]

Hey Tigerman:

I've seen you post a couple times on this issue, so I put something together for you from a few sources. This chart should help answer your questions:

The "volume" in liters listed on the chart should be the actual volume the cylinder will hold (i.e., if you poured water into it, that's how much it would take to "fill" the tank). The "volume" in cubic inches (CI) on the chart is liters converted to cubic inches. The "volume" in cubic feet (CF) is the volume of air the cylinder will hold, at it's rated working pressure.

So, the tank you refer to is "915 cu. in," probably meaning it is a Faber FX-117DVB. The "actual" volume of the tank is 15 L, but when pressurized to it's working pressure it holds 117 cubic feet of air.

I'd prefer metrics also, but I think it would take a constitutional ammendment in this country for it to happen.

Hopes this helps....

 

[DrownedRat]

I have a set of Faber LP 120s that I really love. Filled to 3000 psi I have about 150cf of gas. Not sure about the whole NDL worries as you should be planning your dive then diving your plan
Two al 80s at normal service pressue hold about 77cf, x2 is 154cf. With a working sac of .4 one tank can easily match a buddie with two 80s. Just means changing tanks less often. I also like the length as I"m over 6ft and I find it trims out really well. Again I don't dive wet so the added weight is a real bonus for me as well.

 

[Gr8fldiver]

Why don't more people dive 120's?

In my case it's because I hate diving with something the size of a torpedo strapped to my back. Granted you can't ever have too much air when you're under water but If you're paying by the fill it sucks to have 1800psi of EAN leftover in a tank. I am lucky enough to have Fill Express near where I live so I can get top offs on nitrox and just pay by the cf. For SFla diving I find that a hp 100 is perfect both in size and air quantity.

 

[dawetterdabetter]

In my case it's because I hate diving with something the size of a torpedo strapped to my back. Granted you can't ever have too much air when you're under water but If you're paying by the fill it sucks to have 1800psi of EAN leftover in a tank. I am lucky enough to have Fill Express near where I live so I can get top offs on nitrox and just pay by the cf. For SFla diving I find that a hp 100 is perfect both in size and air quantity.

I dive LP 120's filled to 3700 giving me hours of shore diving fun...something like 3-4 hour dives. being able to dive out to 40' of Commercial Bvld in south FL is an added adventure. And once your in the water it really isn't that much different.

Just my 2 cents

PS Fill Express is a great LDS!

 

[xiSkiGuy]

I have a set of Faber LP 120s that I really love. Filled to 3000 psi I have about 150cf of gas.

Actually you need to fill that LP120 to 3300psi to get around 150cf out of it:

120/2640=.04545

.4545*3300=149.985