Dry Suit Thoughts and Experiences?

[formernuke]

The main thing here is to realize there is more than one way to dive dry, I prefer not using the wing and I did try the wing for buoyancy for a while before adopting my preferred method, avoid dogma and find what works best for you.

Nicely said.

With my first drysuit and a single 120, the air needed for comfort matched what was needed for neutral bouyancy, with my double 50's that is not the case so I'm using wing for bouyancy.

 

[edhjr]

The type dry suit used is a contributing factor buoyancy control and what works best for the individual diver. Communication and experience allow divers to personalize techniques and skills.

 

[Jim Lapenta]

I am still new to diving dry, about 50 dives on my dry suit so far, but yes. I find using my dry suit for bouyency control and comfort is the best for me. My experience is limited however to diving in the NW OH area quarries/wrecks.



I found a section in one of the manuals that came with my dry suit. Specifically it's the user manual for the SI tech dry suit valves. The picture should be attached. It tells me to keep my BCD empty during the dive.

That being said, you have WAY more experience than I do diving, just like my instructor has WAY more experience than me as well. So I usually defer to the experience to become familiar with the material/procedures/conditions and then when I am comfortable tweak as required.

That refers to the dump valve and it requires you to know where your valve is set, how it acts with your undergarments, know your body position, and seems to say that control is automatic with that valve. It's not. You have to get familiar with it. I've seen that manual as well and feel it's a bit misleading as to what the valve does. It seems to generalize the idea and does not get into what to do if you're still sinking. It also doesn't tell you that you can ascend at a rate that the valve will not handle the amount of air trying to escape from it at a fast enough rate.
Ideally the amount of air needed to offset squeeze can be enough to maintain proper buoyancy.
However, the risk increases when you may have more weight than you actually need and you have reduced the squeeze to where it's comfortable but you are still sinking. Are you going to add to the bubble in the suit when it's not necessary? Why? Add a bit to the BCD and you don't have to worry as much about the one in the suit shifting around.
If you start to ascend, as a newer diver, what are you used to doing? Probably dumping air from the BC. Good. Do that.
Then adjust the dump valve on the suit and make sure you're in a position where it will actually work.
A smaller bubble in the suit and in the BC is not beyond the abilities of the properly trained diver. If it is, I'd question whether they should be a drysuit to begin with.
Get your SDI Drysuit manual and open it to pages 86-90.
When we were writing the manual, one of the training department staff was in contact with several drysuit mfg's. None of them recommended using the drysuit for primary buoyancy. We also recognized that the new suits/undergarments may not require as much air to relieve the squeeze and stay warm.
The air in the BC is easier to manage than that in the drysuit. Which is why we recommended keeping the air in the suit to a minimum and using the BC as well when needed for added buoyancy. I could not use my suits for primary buoyancy on most of my dives. It'd require putting more air in the suit than was necessary and for no added benefit.

 

[Rose Robinson]

BC for buoyancy, not the suit.

Hi Marie,

The only time I have air in my wing, is on the surface pre-descent, and on the surface post ascent, at all other times, my wing is empty.

During the dive, I make all slight adjustments with the suit, and it doesn't take much.

My suit fits snug, no wrinkles, no over-bulk, one quick shot of air in, one/two bubbles out, that's all it takes.

With little exception, my typical depth is 150 ft. I've never had to add air to my wing to stay neutral, that includes slinging small deco bottles, 3AL 40's, 3AA LP 50's.

LOL,

Rose

 

[Gandalf-the-Diver]

Only enough air to take the squeeze off and for warmth IS what SDI teaches. Drysuit for buoyancy seems to be PADI.

I did my OW and AOW with PADI, in a drysuit. My instructor told me that I should use my bcd for buoyancy and suit for squeeze only. She also told me, some divers prefer to use their suit for buoyancy, and that I should see what works for me best.
I use my suit to prevent squeeze and for warmth only.

 

[stretchthepenn]

And I have a confession. When I am doing decompression stops at the end of a technical dive, I frequently use my drysuit for buoyancy. If I am on a stop and feel a bit heavy, a brief touch of the inflator valve on my chest does the trick, and when I go to the next stop, a slight tilt of the shoulder gets me neutral again. I learned that watching instructional videos on decompression stops. The videos did not "say" to do that, but it was obvious that they were dong that.

Since we're confessing our sins, I'll share. One time (at band camp), I was messing around in the shallows, experimenting with my SM gear, and I ended up really heavy. I deflated my BCD, closed my drysuit's dump valve all the way, inflated myself until I looked like the Stay-Puft Marshmallow Man, and used my suit to control buoyancy. Darned if it wasn't the absolute easiest and most stable dive ever. Zero effort in maintaining depth, zero changes in depth; I cruised like a frickin' zeppelin.

 

[Wibble]

We have all developed different techniques; the right one is the way that works for you.

Do bare in mind that a technique will change according to your circumstances: winter v summer; OC v CCR; the number of stage/bottom/deco bottles you're taking; steel or ali backgas; the weight of other removable kit (reels+SMB); your underclothes (did you forget the extra layer -- oops!)

Thus don't get wedded to one technique.

BTW I have experimented with tightening the drysuit dump and swapping gas from my wing to my drysuit when am decompressing and it's cold -- deco stops last a long time, sometimes an hour or more at 6m/20', where you don't move vertically. Whilst this does provide a bit more warming, it's not that effective as the air migrates to the top of the bubble, i.e. your back, shoulders and legs, so you're still cold on your front. I'm always acutely aware that any need to dump may need a quick turn on the drysuit exhaust.

Have heard that some deep cavers put a piece of carpet down the front of their drysuit to give more insulation on the front.

The best tool for keeping warm is obviously a decent set of undergarments and drygloves. This is nicely augmented by a heated vest or even a heated undersuit. They work well in cold water, but there's a big but... if you're relying on the heater and it's not working, you're in for a very long and cold dive shivering and trying to do deco exercise.

 

[happy-diver]

As an open water diver I borrowed the Padi video from the dive shop and jumped off a boat
Later after getting bored with dumping through my cuff seal I installed an Apeks dump valve

 

[Wibble]

I borrowed the Padi video from the dive shop and jumped off a boat

Kind of describes my "speciality course".

Tip: don't take a drysuit speciality course in a warm resort location. Go somewhere cold where they actually dive with drysuits!