Steel vs aluminum 40 for redundant: which is better?

[Jared0425]

I can hand off my aluminum 40 much easier than my back mount doubles to someone in need too. Nothing wrong with ponys for people who want a single rig set up.

Steel 40s are mostly obsolete for sling bottles now. CCR is about the only widespread use of them. I use to dive steel 40s for pure O2 and Aluminum 40s for nitrox under each arm. However, I use the Aluminum 40 for O2 and a aluminum 80 for nitrox and I don't have to mess with my rig weighting anymore.

 

[coldwaterglutton]

You probably meant to write "40 cu ft" (rather than "40L").

rx7diver

Haha, yes otherwise that would be a very very big tank!

 

[coldwaterglutton]

@coldwaterglutton NE diving is still sort of the wild west. I love it, but as you can see there's a lot of controversy about the way we / they dive.

I've seen independent doubles, ponies, manifolded doubles.. even a few SM. It all works fine if your son practices. Slinging a 40 and doing a gas switch isn't rocket science, but he should get some practice somewhere benign before the trip.

Good luck and have a blast making memories!!!!!

Interesting on the practice point. I was originally taught years ago to keep the pony valve in the off position until needed to prevent an accidental free flow from the pony regulator. I didn't follow that and always opened it before the dive, figuring I didn't want to mess with that in an out-of-air malfunction at depth. That also meant as little headache as possible - just grab the red regulator and breathe.

Knock on wood I've never needed the redundant air other than when I dip into it for ascents to push bottom time on the main tank, but I only do so at much shallower depths.

 

[Nick_Radov]

I'm not sure I agree with that and many divers I've gone with - far more experienced than me - dive on single tank and pony. On 27% that's a 12 minute no-deco limit and I find I have plenty of air when back up top. No need to schlep doubles for that kind of affair.

It's certainly possible to dive with a screwy rig and make it work — as long as nothing goes seriously wrong. I just don't understand why some divers seem to intentionally make things harder than necessary. A small set of doubles with an isolation manifold isn't significantly heavier or harder to carry than a single plus a stage (or "pony").

After diving for 25 years I have learned not to trust experience as an indicator of skills or knowledge. Some of the worst advice I've ever heard came from some of the most "experienced" divers — at least in terms of years or number of dives. Some divers have done only 100 dives and deliberately improved on every dive. Other divers have done 1000 dives and reinforced the same bad habits on every dive.

 

[grf88]

Interesting on the practice point. I was originally taught years ago to keep the pony valve in the off position until needed to prevent an accidental free flow from the pony regulator. I didn't follow that and always opened it before the dive, figuring I didn't want to mess with that in an out-of-air malfunction at depth. That also meant as little headache as possible - just grab the red regulator and breathe.

Knock on wood I've never needed the redundant air other than when I dip into it for ascents to push bottom time on the main tank, but I only do so at much shallower depths.

Pony always on, deco or stage off until required.

 

[grf88]

Pony always on, deco or stage off until required.

It's certainly possible to dive with a screwy rig and make it work — as long as nothing goes seriously wrong. I just don't understand why some divers seem to intentionally make things harder than necessary. A small set of doubles with an isolation manifold isn't significantly heavier or harder to carry than a single plus a stage (or "pony").

After diving for 25 years I have learned not to trust experience as an indicator of skills or knowledge. Some of the worst advice I've ever heard came from some of the most "experienced" divers — at least in terms of years or number of dives. Some divers have done only 100 dives and deliberately improved on every dive. Other divers have done 1000 dives and reinforced the same bad habits on every dive.

Nothing screwy about using a pony bottle and as previously stated it is fully redundant. Why do some insist that following GUE is the only way to go, there is more than one way to dive.

 

[justinthedeeps]

Yeah don't do the steel pony. Why did you want the steel one?

That said, I did carry a steel LP50 as a side slung cylinder a few times. It doesn't bother me at all in a drysuit.

The mini LP50 doubles are great if you can always get them refilled immediately--like right after each dive. Some ops will do that. I took some to Gods Pocket. They refilled them right on the boat, and thanked me for being the last fill because I only needed ~2600psi in them.

But if not, then you're back on someone else's tanks for the meanwhile. And you could have just carried your alum S40 instead (as most others suggest). So just get the S40 (or an S30). I split up my LP50s a while ago.

You don't really need that manifold between cylinders, it turns out. Sidemounters don't either. Someone tell me when they ever actually needed that manifold, even once?? Twinsets don't make sense for 95% of divers. Shockingly true! Traditions, though. Maybe in a cave.

Once you are in tropical open water territory, just take a rigging kit and a reg, clip on an extra S80 if/when you need it. There's your two tanks. No manifold, no problem. Never had trouble with trim etc either. You can ascend safely on one good tank in open water.

 

[Nick_Radov]

I wouldn't rely on a buddy for backup air in the cold, dark and gloomy conditions here in NY.

And now we come to the crux of the issue. Your dive buddies (and other members of the integrated team) are your most important pieces of dive "gear". If you can't rely on your buddy then you can try to use various convoluted gear configurations to compensate for that fundamental problem but the results will never be optimal. Let me suggest that you rethink your fundamental approach here.

There's nothing special about NY. I've dived in "cold, dark and gloomy" conditions in California, Washington, Massachusetts, Ontario, Finland, etc. So what. The correct equipment and protocols work equally well for sport diving anywhere.

 

[coldwaterglutton]

Pony always on, deco or stage off until required.

I was taught circa 1989, so I'm sure thinking has evolved. To me it seemed obvious the pony should remain on.

 

[grf88]

And now we come to the crux of the issue. Your dive buddies (and other members of the integrated team) are your most important pieces of dive "gear". If you can't rely on your buddy then you can try to use various convoluted gear configurations to compensate for that fundamental problem but the results will never be optimal. Let me suggest that you rethink your fundamental approach here.

There's nothing special about NY. I've dived in "cold, dark and gloomy" conditions in California, Washington, Massachusetts, Ontario, Finland, etc. So what. The correct equipment and protocols work equally well for sport diving anywhere.

Not everybody dives as an integrated team, in fact most don't but tend to dive with casual buddies or even strangers, especially when on vacation. Frankly I am tired of those that try to dissuade people from using a redundant air source such as a pony because what happens is rather that starting to use doubles, which by the way unless independent are not fully redundant, they revert to just relying on their buddy as a backup which is not a reliable source. Drink the Kool Aid all you like but do not criticize those that wish to take the simple safety precaution of using a pony bottle. Actually PONEE bottle, Piece of Necessary Emergency Equipment.