DIR- GUE Balanced rig with a thick wetsuit - mathematically impossible?

[Ayisha]

This has been a ridiculously overthought thread already...

Well of course, this is ScubaBoard

 

[Nick_Radov]

Personally, I have always preferred, in the last 13 years anyway, to achieve a balanced rig without ditchable weight, so I don't have any. I can swim up my rig from depth, so I've never needed any, even back when ditchable weight was common. As long as you could swim it up, it was balanced.

Swimming up isn't really the issue. Any of us can swim up an extra 15lbs of back gas weight without a wing. But how do you intend to stay up once you reach the surface? In some places such as California we frequently do shore dives with long surface swims. Even when boat diving you might be treading water for a while until they pick you up. Drysuits help to an extent but they don't work well as surface floatation.

 

[Eric Sedletzky]

Swimming up isn't really the issue. Any of us can swim up an extra 15lbs of back gas weight without a wing. But how do you intend to stay up once you reach the surface? In some places such as California we frequently do shore dives with long surface swims. Even when boat diving you might be treading water for a while until they pick you up. Drysuits help to an extent but they don't work well as surface floatation.

I dive in Northern California in 7mm wetsuits.
What I found is when I achieved proper weighting, meaning that I can hold a fifteen foot safety stop at the end of a full length dive with a near empty tank and no air in my wing, I do not need any air in my wing at the surface. If I’m neutral at 15’ then when I surface I will definitely be positive. In fact, I found that with this proper weighting in practice I can actually float on the surface with a full tank prior to descending. To descend I have to tip forward and swim down like a freediver, but that is incidental to being properly weighted.
So there is never a time that I worry about being too heavy on the surface. Besides all that I have a weightbelt on so if I really need to get light, lets say I have to exit onto some rocks and need all the help I can get, I would ditch the belt for safety.
We also kayak dive quite a bit and having a weightbelt makes it a lot easier to get all gear on in the water. Diving wet off kayaks is also the way to go. Drysuits suck for kayak diving IMO.

 

[Ayisha]

Swimming up isn't really the issue. Any of us can swim up an extra 15lbs of back gas weight without a wing. But how do you intend to stay up once you reach the surface? In some places such as California we frequently do shore dives with long surface swims. Even when boat diving you might be treading water for a while until they pick you up. Drysuits help to an extent but they don't work well as surface floatation.

Like the reply above, I am also correctly weighted and haven't had any issues floating at the surface at the beginning of a dive. For example, when I need to do a hot drop (jumping in without inflating) to hit a target depth/spot quickly in a current, I don't just sink but am at the surface, re-connect quickly with my team, have a l-o-n-g exhale, and start descending. If I were overweighted, I would sink rapidly.

If my buddy and I have signalled to go down, so I have dumped some gas out of my wing and descended a bit, but then the buddy decides to go back to the surface, I don't have to inflate again to go back to or stay on the surface. Just a sharper inhale begins the ascent and I stay on the surface without issue. Again, if you're overweighted, this would be more of an issue.

If I had to wait on the surface a long time? I imagine I would still be breathing from my reg and the tank would become less negative.
Although a DSMB/SMB may not be considered actual redundant buoyancy, a closed circuit SMB will certainly do the trick and a tired diver can rest on it. I watched just that in the Maldives a few months ago.
I always have an SMB and spool in my pocket.

The rear dump valve on the wing is interchangeable with the dump valve on the SMB, at least with Halcyon, so if the rear dump valve is the issue, an on-the-fly repair could be made if motivated enough.

But this thread wasn't about staying at the surface without ditchable weight and a failed wing or a perfectly good drysuit.

Like it or not, the GUE balanced rig definition never required ditchable weight for a recreational rig. It may or may not have included ditchable weight. And yes, as long as you could swim up your rig with a full tank and failed wing, and also maintain your last 10 foot stop with a nearly empty tank, you were balanced. There's even less emphasis on ditchable weight now, but more emphasis on being correctly weighted and nudging toward redundant buoyancy and warmer/appropriate exposure protection.

 

[Twiny]

Bucher did show how to dive in air at more than 100m without BCD...
After decades of practice of this aspproach done by coral hunters, everyone here learned that a stupid plastic bag provides a life-saving buoyancy help subdstantially with no cost and no space - weight - problems.
So I find advisable to always have a plastic bag in my pocket.
It can also be useful for carrying something you have found on the bottom or for many other purposes...

Hi, how do you purge your plastic bag on your way up ? How do you secure it on you ?

 

[lowwall]

Hi, how do you purge your plastic bag on your way up ? How do you secure it on you ?

I've never done this, but it's not hard to imagine how it works. I'm picturing a typical disposable plastic grocery shopping bag or maybe the thicker ones that are meant for reuse.

For purging- It's open. You can squeeze it or tip it.

For securing- if it's got air in it, you don't. Hold it in your hand. If you are using it as a lift bag, loop the handles around the object so you can ditch both if necessary. If you're just using it as a carry bag, it's got handles. You can tie it or clip it on anyway you want as long as you have something to cut it free if it gets entangled.

 

[Angelo Farina]

Hi, how do you purge your plastic bag on your way up ? How do you secure it on you ?

You keep it in your hand (they have two handles, being designed for carrying groceries).
If it is providing too much buoyancy, you can easily squeeze it for expelling the air in excess.
Just try with a small one (5 liters), it is very handy and simple to manage.