Question 40 or 50 lb wing for doubles? And what about (future) stage tanks?

[NothingClever]

In a drysuit?

Wetsuit. I’m comfortable diving an LP85 twinset wet. Any cylinder above that I acknowledge needs to be in DS.

 

[inquis]

I'm leaning toward the 50 for the little extra lift as by the numbers, the 40lb seems to be cutting it a little close for me.

Which numbers? Gas weight in LP85s/HP100s & 7mm wetsuit compression is 25-27 lbs. Do you have larger cylinders? (Hopefully not with a wetsuit...)

ETA: multiple deco & bottom stages might put you close to the 40 lb, but running a drysuit drops the lift requirement (no suit compression).

 

[BcunningPDX]

Which numbers? Gas weight in LP85s/HP100s & 7mm wetsuit compression is 25-27 lbs. Do you have larger cylinders? (Hopefully not with a wetsuit...)

ETA: multiple deco & bottom stages might put you close to the 40 lb, but running a drysuit drops the lift requirement (no suit compression).

My set up is a bit different than OPs, but I have been looking at the Hydros 50 wing as an option and was looking for some feedback on it. My current configuration in salt is a single tank (Faber HP120) w/ trilam drysuit and 40lb wing. I'm moving to doubles (twin Worthington HP120s) w/the rest of gear remaining the same and wing size TBD. Here are the weights of my current set up vs what I would be moving towards. Assuming my numbers are correct and the weight I need at the end of the dive must remain constant to hold a safety stop, it seems that a 40lb wing would not be enough at the start of the dive and would certainly be insufficient if I were to have a drysuit failure. A 45lb wing seems a little too close for comfort, and a 60lb wing seems like over kill....All that being said, I am still very new and open to advice from more experienced divers!

 

[inquis]

@BcunningPDX, that's a great analysis overall. Any wing will handle the gas weight, so it's a question of handling a total suit flood where you might be -43 lb buoyant. This also ignores the approximately +6 lb lung buoyancy or any other redundant buoyancy devices (e.g., DSMB).

Personally, I feel a *total* suit flood is very, very difficult. I've even intentionally tried to flood my suit by opening the neck seal. It was taking forever, so I opened my suit zipper about a foot. Even then, I had to orient myself zipper up to lose the significant amount of gas that was trapped.

Obviously, the 50 lb is the more conservative choice and will be optimized for the worst case scenario. The 40 lb is optimal for the 99.9% use case. Personal preference will dictate where you lie on the spectrum of risk tolerance/mitigation.

 

[BcunningPDX]

@BcunningPDX, that's a great analysis overall. Any wing will handle the gas weight, so it's a question of handling a total suit flood where you might be -43 lb buoyant. This also ignores the approximately +6 lb lung buoyancy or any other redundant buoyancy devices (e.g., DSMB).

Personally, I feel a *total* suit flood is very, very difficult. I've even intentionally tried to flood my suit by opening the neck seal. It was taking forever, so I opened my suit zipper about a foot. Even then, I had to orient myself zipper up to lose the significant amount of gas that was trapped.

Obviously, the 50 lb is the more conservative choice and will be optimized for the worst case scenario. The 40 lb is optimal for the 99.9% use case. Personal preference will dictate where you lie on the spectrum of risk tolerance/mitigation.

Thanks so much for the reply and sharing your experience with trying to flood your suit! Makes sense that there would still be some air trapped despite even having an open zipper. I had also not considered lung buoyancy when thinking about it.... the only other factor I was considering was the ability of the wing to support the rig (@-43lbs) itself if it needed to be removed at the surface, hence leaning towards the 45lb or 50lb wing.

 

[crofrog]

My set up is a bit different than OPs, but I have been looking at the Hydros 50 wing as an option and was looking for some feedback on it. My current configuration in salt is a single tank (Faber HP120) w/ trilam drysuit and 40lb wing. I'm moving to doubles (twin Worthington HP120s) w/the rest of gear remaining the same and wing size TBD. Here are the weights of my current set up vs what I would be moving towards. Assuming my numbers are correct and the weight I need at the end of the dive must remain constant to hold a safety stop, it seems that a 40lb wing would not be enough at the start of the dive and would certainly be insufficient if I were to have a drysuit failure. A 45lb wing seems a little too close for comfort, and a 60lb wing seems like over kill....All that being said, I am still very new and open to advice from more experienced divers!

Are these the weights you measured in water?

My double faber 133s in water weighs 31.4lb with bands, manifolds, and regulators, my halcyon steel plate is ~4lb in water, and my focus 2 is 1.2lb.

 

[happy-diver]

With manifolded Faber 100s I'm still using a 40lb wing with 10mm of neoprene over my torso, forever

unless I'm using a drysuit

 

[BcunningPDX]

Are these the weights you measured in water?

My double faber 133s in water weighs 31.4lb with bands, manifolds, and regulators, my halcyon steel plate is ~4lb in water, and my focus 2 is 1.2lb.

All numbers are supposed "in water" weights pulled from manufactures websites, but could certainly be inaccurate. I do have the Halcyon long steel plate ( a little heavier) and a larger battery canister for my Flare (also a bit heavier) and the Worthington HP120s are a little heaver to start than the Faber 133s (if you trust the manufacture spec sheets!) The only numbers I could not verify online were the bands and hardware... I took a guess based on some discussions I found on SB, but also could be incorrect. Certainly the best way would be to actually weigh it all personally for the actual answer!

 

[crofrog]

All numbers are supposed "in water" weights pulled from manufactures websites, but could certainly be inaccurate. I do have the Halcyon long steel plate ( a little heavier) and a larger battery canister for my Flare (also a bit heavier) and the Worthington HP120s are a little heaver to start than the Faber 133s (if you trust the manufacture spec sheets!) The only numbers I could not verify online were the bands and hardware... I took a guess based on some discussions I found on SB, but also could be incorrect. Certainly the best way would be to actually weigh it all personally for the actual answer!

the canisters are really pretty neutral in the water. Lithium isn't very dense and they displace a decent amount water.

My flare EXP is .4lb
My 20ah canister is around 3 in water.

 

[BcunningPDX]

the canisters are really pretty neutral in the water. Lithium isn't very dense and they displace a decent amount water.

My flare EXP is .4lb
My 20ah canister is around 3 in water.

My 20ah canister is the same as yours!