SMB as backup lift source.

[Storker]

I wouldn’t want to swim that up either.

Hence the drysuit

So... what you're really saying is that it's impossible to have truly balanced rig - at least according to the definition you've given upthread - if you're doing fairly advanced tech dives?

 

[PfcAJ]

So... what you're really saying is that it's impossible to have truly balanced rig - at least according to the definition you've given upthread - if you're doing fairly advanced tech dives?

Without going back to look, I probably wrote something to the effect of “if you can’t swim against it, you need a drysuit”.

Deco bottles can be jettisoned and aren’t really part of the equation.

But to further complicate the matter, you might need to ADD weight in order to maintain the “neutral at 15’ with empty tanks and empty wing” requirement. If that’s the case, having all or some of that in a ditchable format might allow you the option to swim against your tanks. It all depends on you, your body composition, and your exposure protection.

There’s no substitute for testing. All the supposing in the world can’t replace real validation.

 

[Jiminy]

Without going back to look, I probably wrote something to the effect of “if you can’t swim against it, you need a drysuit”.

Deco bottles can be jettisoned and aren’t really part of the equation.

But to further complicate the matter, you might need to ADD weight in order to maintain the “neutral at 15’ with empty tanks and empty wing” requirement. If that’s the case, having all or some of that in a ditchable format might allow you the option to swim against your tanks. It all depends on you, your body composition, and your exposure protection.

There’s no substitute for testing. All the supposing in the world can’t replace real validation.

Has anyone tested how much weight a normal human actually swim up from 130 or 200 ft?

 

[PfcAJ]

Has anyone tested how much weight a normal human actually swim up from 130 or 200 ft?

Probably not much.

Once you stop sinking then you can futz with your lift bag or whatever.

 

[-JD-]

Alright, I have decided I will go ahead and get a drysuit. What is the best value model? Also, I plan to lose 50 pounds of body weight over the next 6 months. Is there a drysuit which will fit me both now and after the weight loss?

I have a single bladder wing. I am debating adding a second bladder to it. The only thing giving me pause is the GUE website saying not to dive double bladder wings.

The Aqualung (formerly Whites brand) Fusion suits may work for you. Because the outer coverings are highly elastic, they can fit a broad range, within limits. Depend on where you start and end. Check the size charts ...

One among many relevant threads: Confessions of a former Fusion hater

 

[MichaelMc]

An earlier 42 page thread on the balanced rig subject
Question about “balanced rigs” and having all ballast unditchable

With a definition on page 38:
Question about “balanced rigs” and having all ballast unditchable

A) Weighted so that you're neutral at 15' with no gas in your BC and near empty tanks
B) Light enough to allow you to swim to the surface in event of a BC failure with full tanks

If you need to add so much weight to accomplish A that you can no longer do B, some of that weight needs to be ditchable so that you can accomplish B.

If your tank choice precludes you from doing B (heavy steel doubles), then you need a way to *immediately* establish positive buoyancy (drysuit). Fiddling with lift bags and trying to orally inflate a double bladder wing is *not* a viable solution when you're plunging toward the bottom.

I'm not sure why a first BC bladder can fail but a dry suit can't, but that's just me...

 

[Graeme Fraser]

An earlier 42 page thread on the balanced rig subject
Question about “balanced rigs” and having all ballast unditchable

With a definition on page 38:
Question about “balanced rigs” and having all ballast unditchable



I'm not sure why a first BC bladder can fail but a dry suit can't, but that's just me...

Yes a drysuit is more likely to fail but then you've got the BC to get you out of trouble. You'll never have the DS with out the BC, but you may have the BC without the DS. The chances of both failing on the same dive.... Negligible!

 

[Coztick]

I couldn't find the video but it demonstrated how to rig a dsmb to control bouyancy.

It entailed unrolling a dsmb about half way and stuffing the rolled top section under the waistband.
Fold the remaining 3 feet in half, away from your body, leaving the open bottom at your fingertips and the bubble against your chest.
This seemed to offer easy inflation and deflation while horizontal or vertical as well as staying somewhat streamlined.
Far better than climbing the line.

 

[PfcAJ]

An earlier 42 page thread on the balanced rig subject
Question about “balanced rigs” and having all ballast unditchable

With a definition on page 38:
Question about “balanced rigs” and having all ballast unditchable



I'm not sure why a first BC bladder can fail but a dry suit can't, but that's just me...

A drysuit can fail.

That’s why you’ve got both a drysuit and a bc.

 

[60plus]

One of the SMBs I have used was just a tube with one end closed, the other fully open. it would be easy to use it for variable buoyancy by just holding it part way up.