Steel or Aluminum?

[Sarah]

Aluminum corrosions tends to be self-limiting, but aluminum cylinders are awfully bouyant nearing empty.

Steel tanks corrode easily, are more expensive, are far more costly but are available in a larger variety of sizes.

So which do you prefer and why?

[JS1scuba]

Aluminum corrosions tends to be self-limiting, but aluminum cylinders are awfully bouyant nearing empty.

Steel tanks corrode easily, are more expensive, are far more costly but are available in a larger variety of sizes.

So which do you prefer and why?

Babe,

This might help you.

Choosing a scuba cylinder today is easier than it has ever been. With more than 100 products available there is a cylinder for everyone's needs. Bouyancy charachteristics are easily understood as are all the other specs.

The "standard" aluminum 80 has been around for more than 20 years and is the most manufactured product. Between Luxfer and Catalina cylinder companies they make a combined 125-130,000 units a year. BUT that does not mean its the best tank for all people. It's just a good general tank that does not allow you to sink like a rock and will help you get up when you run out of air. (for single tankers) It's bouyancy when empty is only 4 lbs positive. not all that much.

Aluminum cylinders today are well made and will last a very long time so long as you care for them. Just like your BMW if you take care it will last a while if you dont it will get nasty.

Aluminum Cylinders are available in 4 cuft - 100 cuft sizes. With a large selection of ponys. Popular sizes are 50, 63, and 80 cuft.


Steel cylinders today are made by the following companies for US distribution. Faber, Pressed Steel, Asahi, and Worthington. All totaled they may be responsible for 100,000 cylinders a year with Faber being the largest seller.

Faber cylinders are chrome molybedenum steel that is spray galvanized, epoxy painted and finished with a clear poly-urethane coating. These cylinders will last forever. I have some now close to 20 years with No rust and no corrosion. Faber has the widest selection of cylinders from 12 cuft to 149 cuft. 19 sizes are available.

Pressed Steel makes a hot dipped galvanized cylinder. This product is a "metal finish" that will resist corrosion. However because of the hot-dip galavanization process it is more suseptible to internal flash rust at manufacture. This is not a problem so long as the cylinder is cared for.
Sizes are 45 cuft - 130 cuft -- 9 sizes available.

Asahi makes a spun steel tank that is triple coated like the Faber but in limited sizes 80, 100, 120 cuft 3 sizes available.

Worthington makes a cylinder similar in nature to the PST tanks. Orignial Worthingtons were painted now they are hot dip galvanized. 13 cuft - 130 cuft --- 14 sizes are available.


The key to taking care of cylinders is to only have them dry slow filled, and to only fill them with purified clean dry air or appropriate mixes gases. Any water that gets into a cylinder will begin to immediately damage it.

As to cost on products. The aluminum 80 today is selling in the 155-165 price range with a proper valve. A typical aluminum cylinder will go out of service in about 15 years, they are also more suspeptible to failing hydro because they are not as "elastic" as a steel cylinder is.

A corresponding steel cylinder in the 80-100 cuft range is about $100 more. BUT will require 10 lbs less balast. so you save $50 there on less lead. So the Steel tank is net about $50 more.

As aluminum and steel prices soar you can expect tank prices to go up another 20% in 2008.

Choosing a cylinder size is critical to your diving.

Got a tank question ? Just ping me ..........

Cheers

[dalehall]

So which do you prefer and why?

Aluminum, because that's what I got for my birthday.

[hbh2oguard]

have both but steel is a lot nicer. I have an extremely old steel 72, it's first hydro was in 1963 and it just passed hydro and vip with no problems didn't even need to get cleaned - had no rust.

[Zero]

Should i throw a spanner in the works and say Inconel?
Just a dream at the moment but hopefully not for too much longer.

Matt

[seasnake]

I have both but for the capacity I find the steel tanks to be smaller in size, and the few extra lbs of neg bouyancy is nice.

[jeff98208]

i would dive with the aluminium tank, but then i'd just float. so i use the steel tanks.

[amtrosie]

It depends on the dive My cave dives are done with steels. My Intermediate ocean dives are done with double Al. 80's. Deep and/or long ocean dives are with double steel 95's (am thinking of upgrading to 104's or 119's) All stages and deco bottles are Al 80's or 40's depending on the gas requirerment. The argon bottle is Al 6 or 13 cu.ft., again depending on the duration of the planned dive. For the shallow ocean dives, I still like the single steel 72, in very warm water---of course.

My first set of double's were a set of steel 72's. This was a good intro into the diving with doubles. The single 95(steel) is also a good intro into the "more gas required dives" while still using the BC single reg set-ups.

So My answer? IT ALL DEPENDS

[seasnake]

I doubled up a set of PST steel 130's ... had to rig up an eye where the crane could attach to lift me into the water ... ha ha Kidding. They actually aren't too bad, and it sure is nice having all that gas with you ...

[SoCalDiveGirl]

I doubled up a set of PST steel 130's ... had to rig up an eye where the crane could attach to lift me into the water ... ha ha ...

Ron, you're just too cute 130's though, wow- I wouldn't be able to stand up with those things on my back...

But as for me, steel all the way. I do not like Aluminum, except for my stages..