Why don't more people use compact AL100s?

[XxMerlinxX]

As I've been piecing together my kit, I've started looking at tanks and I'm wondering, why don't more people use compact AL100s rather than AL80s? I get that most dive shops use AL80s for their rental gear, so getting weight and trim right and being used to those tanks would be easier when traveling. Barring that, is there anything else that I'm missing? The price difference is marginal, you get more air, they're only about 2 inches longer and an inch larger around, and they're not positively buoyant when empty. Is it because of the extra weight when on land? What about the swing from full to empty?

 

[fire_diver]

It's because an HP100 steel is a much better alternative. Same height as an AL80, same diameter as an AL80, same dry weight as an AL80 and best of all they don't float when empty.

 

[eponym]

First, they're relatively new. See this thread, especially DA Aquamaster's analysis:

http://www.scubaboard.com/forums/tanks-valves-bands/272603-compact-aluminum.html

As long as you're going higher-pressure, why not steel 100s?

-Bryan

 

[Scott L]

.....

 

[JahJahwarrior]

Mid pressure 100s aren't bad tanks, they were my first tank purchase. I doubled them up and they worked ok. Heavy, and don't hold nearly as much air as overfilled lp95's, so I sold them. I don't see that many of them at the fill stations I've worked around before. If I have my choice, I'll usually go with a steel tank, the only aluminum tanks I have uses for are 40's (deco) and 80's (stage, single tanks).

But, if you find a good deal on some, they are certainly not bad tanks.

 

[XxMerlinxX]

It's because an HP100 steel is a much better alternative. Same height as an AL80, same diameter as an AL80, same dry weight as an AL80 and best of all they don't float when empty.

As far as the dimensions go, an inch taller and an inch bigger around aren't huge differences. Dry weight could be an issue if you have a bad back or have to hike to your dive spot, but isn't really an issue for me. These also don't float when empty though.

As long as you're going higher-pressure, why not steel 100s?

It's mostly due to price. I can get two of these for the price of one steel 100.

Interesting wording. In addition to what was just said, they do not appear to be manufactured any longer. At least not by Luxfer and Catalina...

Catalina has them listed on their website, are you sure they're no longer produced?

 

[oxyhacker]

Aluminum tanks can be manufacturered in surprisingly small quantities. A few years back we were looking into getting some oddball rebreather bottles made, and Luxfer's minimum was only one pallet-load, which I think worked out to only about 36 tanks. So it is quite possible that Catalina lists the C100s, but doesn't really make many.

What I don't like about the compact tanks is that they tend to be 3300 psi, and too many dive shops seeing they are aluminum just put in the same 3000 plus a little extra that they put in a standard 80, so a C80 ends up with less air than a standard 80, and a C100 with only a little bit more.

Catalina has them listed on their website, are you sure they're no longer produced?

 

[akdeepdiver]

I have two and I love them. Of course part of that comes because I bought them off craigslist for $50 each. And both of them were pretty much brand new.

 

[scubafanatic]

...much as I love all my 'steelies' , AL is much more tolerant of exposure to salt water/rental abuse/lower purchase price, and most of the time when an op even offers the option to upgrade to a bigger capacity tank, it will be an AL 100, not a 'steelie'.

 

[fdog]

Around here, a couple do get sold, but most folks are more likely to buy steel HP100's for their smaller dimensions and weight. Usually all they do is heft both cylinders at the same time, and the extra cost of steel stops being an issue.

My impression was that the Al100 gets floaty when empty, so that's more lead.

<shrugs> If I lived in a warm salt water location, I might be more tempted to use Al100's for better corrosion resistance.


All the best, James