DAN advocating using drysuit for buoyancy control while diving

[Storker]

IMO it's not used as your primary buoyancy control device. However, if you're correctly weighted, the air added to the suit to alleviate squeeze pretty much balances with the amount of air needed to stay neutral. Just as, with my SAC (15-20 SLM) and my standard tank (10Lx300bar or 15Lx200bar), there's a nice correlation between NDL time and min gas time.

 

[ajduplessis]

For me it was a learning curve that led to a change.

I used to only add air to reduce squeeze and use BCD as primary. Over time I slowly added more air to the suit to encrease warmth to a point where the wing is only used on the surface. I use steel 15ltr twins (hp 120 i think) with 3 stages (2x40's/1x80) and never add any air to my wing up to about 40m. Deeper than this and you will have to start adding lift to the wing.

Using the suit as primary buoyancy is extremely easy and I would recommend the same approach to most drysuit divers with solid experience diving dry.

At the end of the day you must feel comfortable in what ever method you utilize.

 

[Redshift]

For me it was a learning curve that led to a change.

I used to only add air to reduce squeeze and use BCD as primary. Over time I slowly added more air to the suit to encrease warmth to a point where the wing is only used on the surface. I use steel 15ltr twins (hp 120 i think) with 3 stages (2x40's/1x80) and never add any air to my wing up to about 40m. Deeper than this and you will have to start adding lift to the wing.

Is that when you are descending or if you do dives with 2x15l + 3 stages and are shallower than 40m (neutral) you don't need air in your wing?
Or do you have a neoprene suit?

Because to remove the squeeze, there is a certain volume needed and that is the same near the surface or deep.

 

[ScubaInChicago]

Is that when you are descending or if you do dives with 2x15l + 3 stages and are shallower than 40m (neutral) you don't need air in your wing?
Or do you have a neoprene suit?

Because to remove the squeeze, there is a certain volume needed and that is the same near the surface or deep.

That's a 3mil shorty dive with a double bladder wing.

BTW, Boyle would disagree with your last statement.

 

[HeatCker]

a number of the above posts refer to/say "if your properly weighted"
what is the method you use to achieve proper weighting for your style of drysuit diving

 

[decompression]

Balanced rig calc with a buoyancy check for confirmation.


Sent from my iPhone using Tapatalk

 

[HungoverDiver]

That's a 3mil shorty dive with a double bladder wing.

BTW, Boyle would disagree with your last statement.

Well Redshift is correct, the "volume" to remove squeeze is the same at depth and at the surface. However, the amount of gas you need to injected into your suit (i.e. number of "molecules of air") does differ between the surface and depth.

 

[NAM001]

I use the ds air for comfort and the wing for buoyancy. I decided that on one of the first dives I did with the suit. I lost buoyancy control and it became out of control especially upside down. after returning to shore I nuked out the physics and determined that if my wing had 40# lift and the suit had 140# lift I should select the buoyancy device that if depth control was lost the max lift available should be the smallest device. I dive a tls350 and as such it will blow up to,,, upside down,,, michileen man demensions. my wing will only go to its max lift spec and can be vented upside down. I guess I have more recovery options using the wing for buoyancy. Neo ds's may be another story.

 

[ScubaInChicago]

Well Redshift is correct, the "volume" to remove squeeze is the same at depth and at the surface. However, the amount of gas you need to injected into your suit (i.e. number of "molecules of air") does differ between the surface and depth.

I'm assuming you did take an open water course.

Boyle's law - Wikipedia, the free encyclopedia

Volume is decreased by 1/2 as density increases X2 @ 2ATA. Volume is 1/3rd and density X3 @ 3ATA, etc. So NO, the volume is not the same @ depth vs. the surface.

 

[gcarter]

I'm assuming you did take an open water course.

Boyle's law - Wikipedia, the free encyclopedia

Volume is decreased by 1/2 as density increases X2 @ 2ATA. Volume is 1/3rd and density X3 @ 3ATA, etc. So NO, the volume is not the same @ depth vs. the surface.

The volume of the physical space is the same. The surface volume of gas required to fill that space at depth changes. Just like the volume of gas in the cylinder doesn't change at depth while how far it goes does, which he acknowledges.

He quoted "volume", I think for this reason.