Tank comparison Steel V Aluminum

[runway1]

I dive so-cal waters and once I switched from the AL80 to my steel HP100 - WEOOOooooooWhoooooooo!!

1. Lost 10# of lead (28 to 18)
2. FAR better buoyancy characteristics, as previously mentioned and mentioned and mentioned
3. Less lead = easier breathing and more bottom time!
4. +20 Cu Ft of air also = more bottom time!

Worth the diffference? To me - oh yeah!

 

[Divin'Papaw]

I dive so-cal waters and once I switched from the AL80 to my steel HP100 - WEOOOooooooWhoooooooo!!

1. Lost 10# of lead (28 to 18)
2. FAR better buoyancy characteristics, as previously mentioned and mentioned and mentioned
3. Less lead = easier breathing and more bottom time!
4. +20 Cu Ft of air also = more bottom time!

Worth the diffference? To me - oh yeah!

Shall we say that you pay a bit more but get a much better user experience?!

The HP100 is darn close to the perfect recreational tank, if one even exists, for the vast majority of divers, especially non-tropical divers.

I love mine and the only thing better will be when I double 'em!

 

[Nick_W]

I agree that is the main reason, but I'll add one more reason, and that is capacity options. You have a lot more options for capacity with steel, and even shape and size. ie. HP119, versus HP120 are very different in dimensions but hold the same gas. With aluminum the choices are pretty lean when it comes to the larger sizes, al80, al80, al80, or the odd al100.

Oh yeah, definitely. I thought we were comparing 80s to 80s though.

Even still, you can get aluminum tanks in a lot of different sizes. Most of the variety is in sizes smaller than 80cf, but AL100s are too hard to find. What I do like about the HP100 vs. the AL100 is that the HP100 is smaller. But it isn't that much smaller, so for a taller guy like me it really isn't too much of an issue.

So right after cost and buoyancy (if you're on a tight budget AL tank + weights are cheaper than a steel tank), I would put size.

 

[waylander48]

The only other consideration is getting the tank filled a lot of dive shops do not fill HP tanks overseas and in the warm water loactions

 

[Jimmer]

What I do like about the HP100 vs. the AL100 is that the HP100 is smaller. But it isn't that much smaller, so for a taller guy like me it really isn't too much of an issue.

I gotta say I disagree, an HP100 is a lot smaller than an AL100.

Catalina C100, 3300 PSI, 8" OD, 27.3" tall, 46.1 pounds.

PST E7-100, 3442 PSI, 7.25" OD, 24.12" tall, 33 pounds

That's a heck of a difference.

 

[Nick_W]

I gotta say I disagree, an HP100 is a lot smaller than an AL100.

Catalina C100, 3300 PSI, 8" OD, 27.3" tall, 46.1 pounds.

PST E7-100, 3442 PSI, 7.25" OD, 24.12" tall, 33 pounds

That's a heck of a difference.

The majority of AL100s I've seen are 26.2" tall, 8" OD, and anywhere from 39 to 43 pounds.

I said "to a taller guy like me" because I don't have to worry about having to choose between slamming the back of my head on a valve or having a tank riding on my butt. If you're a shorter person, then maybe having a tank that is a couple inches shorter is important.

Basically, this is yet another thing that is coming down to individual needs. I'm tall and using these tanks in warm water, so I'm going to save some money and get the taller, "floatier" aluminum tank. Now, when I dive cold water and if I were shorter, I would go with an HP100 any day of the week and twice on Sunday.

 

[Jimmer]

If you're a warm water guy then I can agree with that. I don't mind the bigger heavier tanks either, since I'm 6 foot 3 and 230 pounds. I dive double LP108's. I don't even want to think about how much weight I would need with double AL100's and a drysuit!! lol

 

[Gombessa]

The only other consideration is getting the tank filled a lot of dive shops do not fill HP tanks overseas and in the warm water loactions

Is this referring to living in the tropics, or traveling there? I can understanding living there, but how many people really lug their tanks with them on vacation? Maybe it's just more common than I imagined?

 

[mkutyna]

Thanks for clarifying. The 10-15 year figure may come from the problems with the 6351 alloy that isn't being used any longer. All aluminum tanks that I'm familiar with are now made using 6061 and hopefully they won't have the issues the older alloy ran into in terms of neck crack failures.

Oddly enough, I encountered a dive shop in the Keys this summer that said they wouldn't fill *any* tank older than 15 years, steel or aluminum. I asked the clerk about the sign thinking it was a mis-print and she confirmed it.

The way I understand it, the "dangerous" aluminum tanks isn't really an age thing, it was a problem with a specific batch of tanks that production stopped by Luxfer about 15 years ago. As you said, the 6351 alloy isn't used anymore so there shouldn't be a problem with buying a tank nowadays and being able to keep it for 15+ years. That all depends on where you get it filled though.

 

[Nick_W]

If you're a warm water guy then I can agree with that. I don't mind the bigger heavier tanks either, since I'm 6 foot 3 and 230 pounds. I dive double LP108's. I don't even want to think about how much weight I would need with double AL100's and a drysuit!! lol

Yeah, I don't think I'd ever dive double ALs. I'm a sinker (some say its the rocks in my head), so a little bit of buoyancy in my tank isn't a big deal, as the tank becomes more buoyant I just let more air out of my BC. But I think two of them might be pushing it and I'd actually have to use one of those weight pouches I have laying around :11:.