Steel versus Aluminum... is steel better?

[Gombessa]

Nearly everyone who dives Monterey in a wetsuit wears steel tanks. They are highly preferred over aluminum tanks, because dropping 6lb of lead from a ~30lb weight belt makes a big difference. Even with that shift to non-ditchable weight, the weight belt is left with ~24lb that can be ditched if needed at depth. As mentioned above, the problem arises from heavy steel doubles with little to no weight on the belt.

 

[RAWalker]

My weight belt is weighted dependant on my wetsuit and whether I'm in fresh or salt water to keep me neutral or mildly negative at depth without my BP&W. The BP needs to have enough weight to keep the empty (500psi) tank from pulling me to the surface at 10' and the wing needs to have enough lift to overcome the negative bouyancy of the BP&W with all gear and a full tank.
For those that haven't already I would suggest taking a peak performance buoyancy class.

 

[jupitermermaid]

Whatever you give a woman, she's going to multiply. If you give her sperm, she'll give you a baby. If you give her a house, she'll give you a home. If you give her groceries, she'll give you a meal. If you give her a smile, she'll give you her heart. She multiplies and enlarges what is given to her.'
So - if you give her crap, you will get a bucket full of BM.

lol.......

The last line used to say: "So - if you give her crap, you will get a bucket full of $h!t" but the mods made me change it

 

[String]

So I'm having a hard time keeping my safety stops when my AL 80 tank is about 800 PSI and less. I'm literally inverted kicking with all my might just to not pop to the surface. This is getting to be way too much and I'm scared every time I go deep now because I"m afraid if I get too tired I will just shoot to the top.

That just means you're under-weighted. Add more lead. The tank isn't your problem, its the fact you aren't heavy enough.

That said i hate aluminium tanks with a passion. They require me to carry more lead than a steel tank to sink, are physically bigger on land and heavier per same capacity than steel and hold a lower pressure therefore less gas.

 

[nereas]

Steel tanks are perfectly fine in cold water even with thick wetsuits. There is absolutely no benefit to using an AL tank in cold water instead of a steel: any weight saved on the AL goes right back to your weight belt. There is absolutely no difference in your total weight between the two.

If you can't swim a steel tank up from depth with an empty wing (personally I can, with ease, and I'm by no means in perfect shape) then all you need to do to protect against the unlikely catastrophic BC failure is to carry a few lbs of ditchable weight separate from your main weight belt/harness/pockets, so that once that is ditched you can swim the rig up again (and not rocket to the surface). This is the concept of the balanced rig.

The "disaster" scenario alluded to above can only happen when one is wearing doubles that are heavy enough that the diver carries no additional weight. If you are wearing doubles, one would hope you are aware of how to manage your weight, so it doesn't really apply here.

(yeah, yeah, I know I'm feeding the troll here)

Hudson, if you truly believe what you yourself are saying, with your currently immense 50-to-100 dive experience, then you should do one or two additional things to enhance your own safety a little bit with your way of diving:

1) get a double-bladder wing for your B/C; and/or

2) carry a 35+ lb lift bag with you at all times.

However these are technical solutions to your precarious configuration which consists of your heavy steel tank combined with your thick wetsuit and heavy weight belt.

The odds are higher for you than for a properly configured diver (one with an aluminum tank together with the thick wetsuit) that you will become a fatality statistic due to a run-away descent on scuba during a B/C-wing failure, based on the way you are diving right now.

So what do you care? Probably not.

Apparently your 50-to-100 dives have given you a false sense of security. The philosophical problem with this manner of bad thinking is formally called "the fallacy of hasty generalization."

Thal has a fallacy list that he posted. You can look it up on there. It is from an atheist website for the prevention of antisemitism. Not a bad list.

 

[MauiScubaSteve]

What do you use in Hawai'i? 3mm wetsuit or 5mm wetsuit?

I personally dive 5mm year round. A few of my coworkers dive 7mm w/hooded vest year round. Many instructor/guides dive 6/5/4, 7/5/3 or something like that.

I dive at work with either AL 80 or steel 100. I take 8 lb off my belt with my jacket BC or 8 lbs out of trim pockets with my BI BC. Personally, the steel tank throws me around more than I like when i roll on my side, but it's great for diving on my back looking at my charges.

 

[seanmcfarland]

Everyone here has had some good comments. This is a perfect time to use and refer to your logbook. If I am diving a new configuration, or new equipment, I do it in a safe and controlled situation. We dive quarries here for training. If you're using new tanks or a thicker wetsuit, throw a little more weight than you think you will need in your BCD (or weightbelt). At the end of your dive (1000 - 500 psi), find a nice platform or other location at about 15 feet, and start playing with your weighting and breathing. If you take 2 lbs out and start to rise in the water on a fully expelled lung, put it back in. Experiment until you have a good balance of weight to boyancy. Shoot to be slightly negative at 15 feet with no air in your BC, a tank with 500 psi, and no air in your lungs. As you inhale you should begin to rise SLOWLY.

That being said, I dive 120 cf steels. Sometimes I have a 30cf pony bottle, sometimes not. Sometimes I wear a 7mm suit with hooded vest and gloves, sometimes a 3 mm. Sometimes I wear a BCD with a backplate, sometimes I wear my 'warm water BCD'. If I'm traveling abroad, 80 cf aluminums are standard. Make notes in your logbook about your equipment and your weighting AND REFER TO THEM. Different circumstances will require weighting. I always strive to be 1-2 pounds heavy at the end of my dive. I would rather put a little air in my BCD to float at my safety stop than struggle to stay down.

 

[String]

Steel is fine for any diver that requires about 2kg or so of weight on a belt to sink.

With thick wetsuits steel is great - it means some weight is off the belt onto the tank. And no suit on the planet compresses to the extent nereas claims. The thicker the exposure protection the more sense steel makes.
The only time i'd consider an aluminium tank for back gas is if i dive without any suit at all. As there is nowhere in the world warm enough for me to consider that i dont want to wear one of the things ever. I quite happily dive in a pool with no suit and a 15l steel tank and mysteriously dont get pinned to the bottom with my 30lb wing.

 

[300bar]

Hudson, if you truly believe what you yourself are saying, with your currently immense 50-to-100 dive experience, then you should do one or two additional things to enhance your own safety a little bit with your way of diving:

1) get a double-bladder wing for your B/C; and/or

2) carry a 35+ lb lift bag with you at all times.

However these are technical solutions to your precarious configuration which consists of your heavy steel tank combined with your thick wetsuit and heavy weight belt.

The odds are higher for you than for a properly configured diver (one with an aluminum tank together with the thick wetsuit) that you will become a fatality statistic due to a run-away descent on scuba during a B/C-wing failure, based on the way you are diving right now.

So what do you care? Probably not.

Apparently your 50-to-100 dives have given you a false sense of security. The philosophical problem with this manner of bad thinking is formally called "the fallacy of hasty generalization."

Thal has a fallacy list that he posted. You can look it up on there. It is from an atheist website for the prevention of antisemitism. Not a bad list.

Are you realy that ignorant.

On this side of the planet we ALL dive steel tanks,wet or dry.Guess you NEVER dived a steel tank.Can't be,other wise you would NEVER give such idiot advice.

AL and steel tanks have the same weight,steel is justa little negative buouyant on the end of the dive, where AL is positive.So for a AL tank you need 2-3lbs just to stay nuteral at the end (500psi) of the dive.

Double bladders and or 35+lbs lift bags is just idiotic(sorry no better word for it)
There is just NO need for them,guess YOU just need to learn to DIVE.

 

[String]

Are you realy that ignorant.

If you've seen some of his posts on the other areas about nitrox, padi, technical diving and so on you'll see he's either a troll or someone claiming knowledge whilst having none. That makes him dangerous.