Best guess, will I be too heavy with this tank?

[Storker]

I'm pretty sure all the DIR types tend to eschew the use of steel tanks.

I'm not sure how many of the tech divers I know who would call themselves "DIR types", but some of them have definitely taken a few sips of that cool-aid.

And unless they're on a 'breather, it's twin 12L 232 bar steels for everyone.

 

[kelemvor]

Maybe up in that frozen tundra. I've seen more than a few guys at Ginnie sporting a pair of al80's doubled up. It wouldn't be my choice, but obviously it was theirs. I remember when I was considering my first tank purchases that a lot of the GUE guys warned me away from steel citing buoyancy concerns. In the end, I decided that a pair of lp108's properly filled giving me almost ~300cuft (~8500l) of gas was worth the weight penalty. I believe their opinion was that if you needed more gas, bring more tanks. I respect their opinion without sharing it. If I lost my wing and drysuit I would definitely have a problem with an extended surface swim.

 

[Doby45]

I've seen more than a few guys at Ginnie sporting a pair of al80's doubled up.

I have never seen this at Ginnie and for a fact not on any diver with a drysuit and blue Hs all over them.

 

[stuartv]

OK, I believe I learned a thing or two here, allow me to summarize.

Based on my best estimates, the 25 lb wing should float the rig, but that's not necessarily the primary concern, it's instead perhaps that I am over-weighted in the event of a wing failure. With a 3 mm suit, 5 lb SS plate, and -7 lb tank when full, at the start of the dive, I'm very likely over-weighted. At the end of the dive? Probably OK. Now, does this even matter considering my diving profile? I have not fully decided, but probably not; again, <30 ft of water. What does have me a bit concerned is floating my rig for long periods of time (in the event where I'm stranded) without being able to ditch said weight (very easily at least) and worse, not having a working wing at all. I forgot to add that most of my diving will be from the shore. I'm considering getting at least a 30 lb wing for situations where I am far from shore and definitely planning to purchase a good quality dsmb in all cases.

If the wing is not working, then it doesn't matter what size it is. If it is working, then 25# seems likely to be plenty of lift.

With an empty (or dead) wing, you're talking about 5# of BP and 7# of tank/gas. So, you're 12# negative? But then if you have a full 3mm wetsuit, maybe only 8 - 10# negative?

At that, most people could swim that up to the surface without any real trouble. Especially from only 30'.

If the wing is totally dead and you get to the surface, and you aren't able to swim to shore or otherwise keep your head above water, your ditchable weight is your whole rig.

A good, 6' SMB can be around 30 - 35# of lift. If your wing is totally dead and you don't want to ditch your rig, that could be made to work to keep you afloat.

Again, if the wing is dead, it doesn't matter what size it is. If the wing is fine, then 25# is probably plenty. I've done numerous dives in 3mm, SS BP, HP120, and HOG 23# wing. Mostly, 10 - 30 miles offshore, diving to 80 - 120 feet, off North Carolina. That 23# wing has never let me down. LOL

 

[1atm]

I have never seen this at Ginnie and for a fact not on any diver with a drysuit and blue Hs all over them.

Its a very common site in Mexico or other warmer water places like eg Egypt

 

[Doby45]

Its a very common site in Mexico or other warmer water places like eg Egypt

Which is NOT Ginnie/North Florida caves.

 

[certainmisuse]

If the wing is not working, then it doesn't matter what size it is. If it is working, then 25# seems likely to be plenty of lift.

With an empty (or dead) wing, you're talking about 5# of BP and 7# of tank/gas. So, you're 12# negative? But then if you have a full 3mm wetsuit, maybe only 8 - 10# negative?

At that, most people could swim that up to the surface without any real trouble. Especially from only 30'.

If the wing is totally dead and you get to the surface, and you aren't able to swim to shore or otherwise keep your head above water, your ditchable weight is your whole rig.

A good, 6' SMB can be around 30 - 35# of lift. If your wing is totally dead and you don't want to ditch your rig, that could be made to work to keep you afloat.

Again, if the wing is dead, it doesn't matter what size it is. If the wing is fine, then 25# is probably plenty. I've done numerous dives in 3mm, SS BP, HP120, and HOG 23# wing. Mostly, 10 - 30 miles offshore, diving to 80 - 120 feet, off North Carolina. That 23# wing has never let me down. LOL

Agreed. I would simply add that the 12#s negative gets less negative as the dive continues of course. And thanks for the SMB info.

 

[Ayisha]

Agreed. I would simply add that the 12#s negative gets less negative as the dive continues of course. And thanks for the SMB info.

Yes. When I first switched to a HP steel 80, I emptied my BC at depth at about 80 feet and swam up my HP steel 80 with my 2 piece 7 mm wetsuit just to make sure that I would be able to swim it up. At first I had to kick a bit, and then the shallower I got the more positive I got. I'm sure a tiny bit of air was trapped in the BCD and expanded, but it was fairly easy.

When I relayed my experience years later to a couple of DIR instructors, they said that swimming up a rig from 40 feet would have been ok.