Why a AL72 Vs AL80?

[Ulfhedinn]

I was looking over tanks for <Stage/Deco> and noticed that Catalina makes a Al72. What would be the reason one would purchase a AL72 over a AL80.

Aluminum 72 (Stage) Catalina 3000 6.90 26.2 27.7 - 0.6 : + 3.5
Aluminum 80 (Stage) Worthington 3000 7.25 26.1 31.9 - 1.8 : + 3.2

 

[Teller]

They only time I would consider a 72 over an 80 is when using a steel 72 for deco.

 

[rongoodman]

I have a couple of the Hymark 72s--they make nice stage bottles.

 

[Ulfhedinn]

I have a couple of the Hymark 72s--they make nice stage bottles.

Since they are thinner? or ?

 

[Teller]

I like 72s for deco since you can get better fills. 2400 psi of O2 in a 3000 psi AL80 vs 2400 psi of O2 in a 2450 LP72.

 

[PfcAJ]

I was looking over tanks for <Stage/Deco> and noticed that Catalina makes a Al72. What would be the reason one would purchase a AL72 over a AL80.

Aluminum 72 (Stage) Catalina 3000 6.90 26.2 27.7 - 0.6 : + 3.5
Aluminum 80 (Stage) Worthington 3000 7.25 26.1 31.9 - 1.8 : + 3.2

I'd only use an al72 if I wanted less gas in a similarly sized package as an al80.

If that seems silly, you're right. it is

On that note, I feel that catalina al80s behave like boat anchors in the water. If you can score a Luxfer, do it. They can be had on the cheap if you look around a bit. I bought one for 60 bucks a few weeks ago (with a din valve).

 

[halocline]

On that note, I feel that catalina al80s behave like boat anchors in the water.

Catalinas are +4 empty, luxfers are +4.4, at least according to the spec charts I've seen. How does that make a Catalina like a boat anchor?

You're not the only person who has expressed a preference for luxfers as stage bottles. I'm curious why?

 

[PfcAJ]

"+4"

In my experience, they're quite a bit heavier than Luxfers. I can't give you any numbers, but every time I pick up a Catalina in the water, I know it before I even look at the tank. With just one, its just annoying, but when you have 2 or 3 (or more), it starts to really suck. Worth avoiding for stages, imo.

 

[Graeme Tolton]

The minimum cylinder size as per NACD is double 71.2cf. One reason to have these cylinders would be to be in compliance on a short penetration cave dive.

Unless you are a fish, or have signifigantly lower sac than your buddies, an 80 would probably be more optimal.

http://www.safecavediving.com/training.shtml

 

[elan]

Catalinas are +4 empty, luxfers are +4.4, at least according to the spec charts I've seen. How does that make a Catalina like a boat anchor?

You're not the only person who has expressed a preference for luxfers as stage bottles. I'm curious why?

Catalinas have more metal on the bottom so that makes them more tail heavy so they trim out worse than Luxfer.

---------- Post added April 12th, 2012 at 12:30 AM ----------

I'd only use an al72 if I wanted less gas in a similarly sized package as an al80.

Or you want to piss off your team mates with a funky selection That would work nice...