Steel vs. Al Tanks?

[Charlie99]

While its true that steels can get overfills, are somewhat sturdier, and are heavier (a lot!) than AL's. Steels are also negatively buoyant when (nearly) empty. This means that a redundant means of buoyancy is needed (if you have a failure of BC at the beginning of the dive, can you swim the rig up to the surface?). It is ill advised to dive steels in wetsuits for this reason (wet suit compression at depth).

1. Usually steel tanks are lighter, NOT heaver, than the aluminum tank of the same capacity.
2. Unless the steel is so negatively buoyant that one is overweighted with no ditchable weight then diving a steel with a wetsuit is no different than diving an aluminum tank with a wetsuit.

I am also looking at a steel tank. When comparing the 80's the steel weighs less is smaller and negative at the end. This means you need less lead and less resisitance in the water.

Should equal easier bouyance control and less air consumption

While there may be less drag due to smaller size, the CHANGE in buoyancy during the dive is exactly the same as with the same capacity aluminum tank. You may wear less lead, but you still need to add/remove exactly the same amount of air as if you were diving an aluminum tank of the same capacity.

 

[pants!]

1. Usually steel tanks are lighter, NOT heaver, than the aluminum tank of the same capacity.
2. Unless the steel is so negatively buoyant that one is overweighted with no ditchable weight then diving a steel

Well, your tank buoyancy is not ditchable.

If you wear a wetsuit and steel tank and little to no ditchable weight, you might have trouble getting off the bottom if your BC fails.

 

[Charlie99]

Well, your tank buoyancy is not ditchable.

If you wear a wetsuit and steel tank and little to no ditchable weight, you might have trouble getting off the bottom if your BC fails.

Yes, but if you ditch more weight than the weight of the air, then you won't be able to control your ascent when shallow, or do a safety/deco stop. This is true whether the tank is steel or aluminum, positive or negatively buoyant.

The need for changing over to a drysuit is more related to amount of wetsuit compression that you can swim up, rather than whether the tank is steel or aluminum. That is, unless you consider doing an uncontrolled ascent is acceptable.

I'd be willing to dive steel and wetsuit, as long as I could get ditchable weight equal to the weight of the gas and still not be overweighted.

 

[Rec Diver]

Well, your tank buoyancy is not ditchable.

If you wear a wetsuit and steel tank and little to no ditchable weight, you might have trouble getting off the bottom if your BC fails.

Well then maybe you should consider ditching your entire BC and tank. Then you would be bouyant in a wet suit. They can always be retrieved later by another diver.

 

[pants!]

Yes, but if you ditch more weight than the weight of the air, then you won't be able to control your ascent when shallow, or do a safety/deco stop. This is true whether the tank is steel or aluminum, positive or negatively buoyant.

The need for changing over to a drysuit is more related to amount of wetsuit compression that you can swim up, rather than whether the tank is steel or aluminum. That is, unless you consider doing an uncontrolled ascent is acceptable.

I'd be willing to dive steel and wetsuit, as long as I could get ditchable weight equal to the weight of the gas and still not be overweighted.

Well, the solution is not to be in that situation in the first place, hence dive a balanced rig, which is a very DIR kinda concept...

 

[Rec Diver]

I was certified in May, and have been loving the sport. I purchased new equipment(mostly sherwood) including my al 80 tanks. I have become involved diving with a group who seem to have mostly compact steel tanks. I realize some of the pros to steel vs. my aluminums such as they are getting a true 80 fill because of the higher psi they are filled to, and that I carry more weight than them due to my increased buoyancy. The only negative feature that I have seen is that a steel is a bit pricy.
Am I overlooking any reason to change or not to change from al. to steel?

I originally purchased aluminium tanks, Luxfer 100's, I wish now I had purchased steel tanks instead.

 

[pants!]

Well then maybe you should consider ditching your entire BC and tank. Then you would be bouyant in a wet suit. They can always be retrieved later by another diver.

Read my other post...

IMO if ditching your entire SCUBA system is a possible planned response to a BC failure something went very wrong in your choice of gear.

 

[Rec Diver]

Well, the solution is not to be in that situation in the first place, hence dive a balanced rig, which is a very DIR kinda concept...

It is?

 

[pants!]

It is?

Yes.

It is a smart diving practice that is central to DIR.

That is obviously not to say that DIR has sole ownership of the concept.. any smart diver will dive a balanced rig.

 

[Rec Diver]

Read my other post...

IMO if ditching your entire SCUBA system is a possible planned response to a BC failure something went very wrong in your choice of gear.[/QUOT]

You think?