BCD requirements for Drysuit

[hypertech]

For the dry suit:
Not if you have the weight on the belt or ditchable on the BC.
Mordern shell suit is slightly negative, neoprene is positive. Flooded undergarment will be neutral. So if you have the ditchable weights on the belt or bc you just ditch it. 20 lb will be more than enough to float the gas in a single tank and the diver.

Huh? What happened to all the lead you were carrying to sink that undergarment before it became soaked. That is what you are compensating for if the suit fails. I would prefer not to "just ditch it" at 100' and rocket to the surface if, say you cut a hole in the suit on a wreck or something.

That 20 pound wing needs to be able to make you positive with all the equipment and the lead you were carrying to be close to neutral before the suit failed. It also needs to be able to float your gear and all the weight connected to the bcd if you take it off.

 

[elan]

Huh? What happened to all the lead you were carrying to sink that undergarment before it became soaked. That is what you are compensating for if the suit fails. That 20 pound wing needs to be able to make you positive with all the equipment and the lead you were carrying to be close to neutral before the suit failed. It also needs to be able to float your gear and all the weight connected to the bcd if you take it off.

You ditch that weight. Just reread my post I put ditchable few times

 

[flots am]

I may begin and do some dry suit diving in the North Sea. I have a BCD (travel light) which can only lift around 20lb which I'm afraid is not enough. Would it be acceptable/safe to pump the dry suit a bit when surfacing in order to compensate for the lifting capacity of the BCD at least until I get some of the weights handed up to the boat crew?

While the math certainly works if you're weighted properly, there's no way in hell I'd be diving in the North Sea in a drysuit with a 20Lb lift BC.

When the conditions suck, I like to be able to produce a lot of positive buoyancy at the push of a button.

flots.

 

[scubajo007]

While the math certainly works if you're weighted properly, there's no way in hell I'd be diving in the North Sea in a drysuit with a 20Lb lift BC.

When the conditions suck, I like to be able to produce a lot of positive buoyancy at the push of a button.

flots.

I think you are right, the North Sea is rough waters, I better buy or rent a BCD with ample lifting capacity if I go for dry suit diving. As a first time dry suit diver it is probably stupid to use a BCD with in adequate lift.

 

[hypertech]

You ditch that weight. Just reread my post I put ditchable few times

I would prefer not to "just ditch it" at 100' and rocket to the surface if, say you cut a hole in the suit on a wreck or something.

 

[TSandM]

The argument about dry suit or BC for buoyancy comes up periodically.

Using the dry suit minimizes task loading, because you only need to monitor and manage one air space. But it can be more challenging, because the dry suit is a large space in which air can migrate (as anybody who's gotten unmanageably floaty feet knows), and dry suits dump slower than BCs, so if you get behind, you can end up in a situation where you can no longer solve the problem.

Using the BC means you have to manage two air spaces, but you have the advantage that one of them is pretty contained and can dump from multiple sites and very fast.

For me, as a newer dry suit diver with buoyancy challenges anyway, using the BC for primary buoyancy and keeping the suit pretty tight worked much better. As I gained facility with buoyancy, I slowly migrated to putting more air in the suit, so I'd stay warmer. I now use the suit entirely for buoyancy with smaller single tanks. For 130s or doubles, I use both, because you pretty much have to.