Why and when

[300bar]

Did alu tanks came on to service.

Older ones seem to be prone to cracks.
They are buoyant when(near) empety.
They are the same weight or more then steel.
Ok they don't rust,but with minimal care and a good (dry air)compressor there is no problem with steel.

So why ALU

Are they cheaper?

Just checked,I've some steel tanks 30years old,never been derusted.

 

[beanojones]

From the Dive operator standpoint Aluminum has some advantages:

Flat bottoms (don't need boots)
Don't rust (rental gear takes a lot more abuse than privately owned gear, and do end up dead empty sometimes)
Float when empty (tanks do fall off boats)
Lighter (generally speaking)

You foreigners spell aluminium funny. Do they add the 'i' at the end in the Nederlands?

 

[Scubakevdm]

Did alu tanks came on to service.

Older ones seem to be prone to cracks.
They are buoyant when(near) empety.
They are the same weight or more then steel.
Ok they don't rust,but with minimal care and a good (dry air)compressor there is no problem with steel.

So why ALU

Are they cheaper?

Just checked,I've some steel tanks 30years old,never been derusted.

They are about half the cost.

 

[300bar]

Aluminium in Dutch

Flat bottoms-OK
Don't rust-they do oxydize so you have to tumble
Float- might be usefull
Lighter- No way,a alu80 weights as much as a steel 12L(witch has a slightly larger volume)

 

[300bar]

They are about half the cost.

You got some 30-50 year old ALU tanks.

As for the price,a 12L steel does 270 euro.Goes a lifetime.
How much would a AL80 do.Standard price,no special deal.
bn

 

[Damselfish]

sometimes the upfront cost is more important to people than saving money 20 years from now.

 

[Scubakevdm]

You got some 30-50 year old ALU tanks.

As for the price,a 12L steel does 270 euro.Goes a lifetime.
How much would a AL80 do.Standard price,no special deal.
bn

I don't know about Euros, but an Hp 100 is about $345
Lp 108 is about $330

AL 80 is about $160

I don't think there's any didfference in the longevity of the tanks, except tanks which were made of one particular alloy, and they were all pre 1989. If anything AL will last longer. I just had to throw away 2 HP 100 steels from 1983 due to corrosion.

 

[SteveAD]

Aluminium in Dutch

Flat bottoms-OK
Don't rust-they do oxydize so you have to tumble
Float- might be usefull
Lighter- No way,a alu80 weights as much as a steel 12L(witch has a slightly larger volume)

Not true. Aluminum oxidation is a self limiting reaction. Once a layer of Al oxide has formed, the underlying material is effectively sealed and stops oxidizing any more.

 

[Couv]

....and reason NOT to tumble....the oxidation prevents the oxidation.

 

[300bar]

Not true. Aluminum oxidation is a self limiting reaction. Once a layer of Al oxide has formed, the underlying material is effectively sealed and stops oxidizing any more.

Very true

....and reason NOT to tumble....the oxidation prevents the oxidation.

So why tumble?