Dry Suit Course Questions

[JanR]

All,

This Saturday I go our local quarry to do my open water dives for my dry suit course.

I recently bought an OS Systmes Nautilus with front entry and can not wait to take it out and do some real (not pool) diving in it.

My pool session went well with the exception of my flooding my suit. Found the problem (head space and timing issue) and don't anticipate the same problem.

The pool session went well and felt very comfortable after the first 15 minutes in teh pool with it.

I have a few dry suit questions which I'm sure my instructor will answer, but wanted to throw out to the collective wisdom of what is Scubaboard.

1. BCD versus Drysuit for bouyancy control. I know PADI and other agencies train to control your bouyancy with your drysuit, not with your BCD. The arguement (as one of my instructors has told me) is as you are adding and venting air to your suit to reduce suit squeeze, concerning yourself with only one inflating device reduces task loading and is easier to dive. Whether you agree with it or not, the rationale at least has some merit (at least to a guy who has yet to dive a dry suit below 11 feet :14 I've read in several threads that it is best to only use your dry suit inflator to reduce suit squeeze but control bouyancy with your BCD/wing. The arguement (if I have read correctly) is the air in your BCD/wing is constricted to a small bladder making trim and bouyancy easier to control as opposed to moving throughout your suit from your boots to your neck. I have talked to my instructor and during my second dive, I will alternate between each method to find what I feel works best for me. I'm sure I have truncated/distorted both arguements above. What are the advantages/disadvantages/recommendations you have for bouyancy control and dry suits?

2. Undergarments. Understandably the undergarments you wear will change based upon water conditions. However, just to get an azimuth check I am planning on wearing silk-weight polartec bottoms and an Under-armor t-shirt as a base layer to wick sweat from my skin. Over this, I will be wearing my undergarments I just received form ebay...the Antartic ones. With water tempatures anticipated to be from 45 to 60 degrees, I feel this should be alright (I've dove to the bottom of the quarry for a 50 minute dive at 42 degrees in a 5 mil and 3/5 hooded vest. The undergarment combination described has got to be warmer than that experience and the subsequent 40 minute dive to the same depths). My question is whether I am using the right logic in layering. Suggestions?

3. Giant Strides. Doing a shore entry over the weekend, so this will not be a factor. However, I've been thinking through this and don't quite understand how you can do a giant stride entry without running the risk of blowing out your wrist/neck seals as you hit the water. Even with crouching before entry to vent out excess air will likely not prevent additional air from being pushed out on entry. My question quite simply is: How do you do this in a dry suit?

4. Misc advice. Any and all suggestions on what I should try, practice, attempt during my dives is more than appreciated. I"m planning to do another dive or two after the official 2 dives of the course to blow more bubbles and continue to practice. Your advice on anything relating to diving a dry suit is most appreciated.

v/r

Jan

 

[avoidthebends]

Climb down the ladder whenever possible to avoid a "burp" from your neck seal. As for the buoyancy question, play with it a little. I usually just have enough air in the drysuit to prevent squeeze and control bouyancy with the BC.

Just my 2 cents.

 

[SurDo2]

Just use your drysuit for bouyancy. At least in really cold water, (2-6 celcius). Keeps you warmer. Forget about your bcd for now.

Your right on track with the undergarments. I find wearing a really thick pair of polarfleece shorts over my long underwear goes a long way to alleviating suit squeeze in that area.

Just jump in. I've seen more people hurt themselves or snag and break equipment trying to climb down a ladder or lower themselves in than I can shake a stick at. Your gonna' get wet anyways. They're more like dampsuits than drysuits.

 

[DeepSeaDan]

All,

This Saturday I go our local quarry to do my open water dives for my dry suit course.

I recently bought an OS Systmes Nautilus with front entry and can not wait to take it out and do some real (not pool) diving in it.

My pool session went well with the exception of my flooding my suit. Found the problem (head space and timing issue) and don't anticipate the same problem.

The pool session went well and felt very comfortable after the first 15 minutes in teh pool with it.

I have a few dry suit questions which I'm sure my instructor will answer, but wanted to throw out to the collective wisdom of what is Scubaboard.

1. BCD versus Drysuit for bouyancy control. I know PADI and other agencies train to control your bouyancy with your drysuit, not with your BCD. The arguement (as one of my instructors has told me) is as you are adding and venting air to your suit to reduce suit squeeze, concerning yourself with only one inflating device reduces task loading and is easier to dive. Whether you agree with it or not, the rationale at least has some merit (at least to a guy who has yet to dive a dry suit below 11 feet :14 I've read in several threads that it is best to only use your dry suit inflator to reduce suit squeeze but control bouyancy with your BCD/wing. The arguement (if I have read correctly) is the air in your BCD/wing is constricted to a small bladder making trim and bouyancy easier to control as opposed to moving throughout your suit from your boots to your neck. I have talked to my instructor and during my second dive, I will alternate between each method to find what I feel works best for me. I'm sure I have truncated/distorted both arguements above. What are the advantages/disadvantages/recommendations you have for bouyancy control and dry suits?

For me it is just an issue of warmth. More air in the suit acts, to some degree, as an insulator against the cold ( argon works better of course ). If warmth is not an issue, I much prefer to just tweak-off the squeeze, then trim with the wing, as has been suggested to you.

2. Undergarments. Understandably the undergarments you wear will change based upon water conditions. However, just to get an azimuth check I am planning on wearing silk-weight polartec bottoms and an Under-armor t-shirt as a base layer to wick sweat from my skin. Over this, I will be wearing my undergarments I just received form ebay...the Antartic ones. With water tempatures anticipated to be from 45 to 60 degrees, I feel this should be alright (I've dove to the bottom of the quarry for a 50 minute dive at 42 degrees in a 5 mil and 3/5 hooded vest. The undergarment combination described has got to be warmer than that experience and the subsequent 40 minute dive to the same depths). My question is whether I am using the right logic in layering. Suggestions?

Layering is good! Know your personal comfort zone for body temperature. Some folks ( especially the ladies ) need more insulation per given water conditions. Try to know the degree of effort required by the dive ( eg.: dealing with current will make you swim harder, plus you now have the added increase in drag from the dry-bag, so you might want to lighten up a bit on the undergarments for such a dive ).

3. Giant Strides. Doing a shore entry over the weekend, so this will not be a factor. However, I've been thinking through this and don't quite understand how you can do a giant stride entry without running the risk of blowing out your wrist/neck seals as you hit the water. Even with crouching before entry to vent out excess air will likely not prevent additional air from being pushed out on entry. My question quite simply is: How do you do this in a dry suit?

Done correctly, this should not be an issue at all. Remember, this entry is designed so that you're head remains above water on entry. Adding some air to your b.c. will assist you to do it properly.

4. Misc advice. Any and all suggestions on what I should try, practice, attempt during my dives is more than appreciated. I"m planning to do another dive or two after the official 2 dives of the course to blow more bubbles and continue to practice. Your advice on anything relating to diving a dry suit is most appreciated.

Some use ankle weights, some don't. I prefer not to, as it makes it easier to fin the "modified frog kick" - a kick-style worth perfecting. Pay close attention to your trim, as allowing your feet to rise can become problematic quickly & is a common issue with new dry-bag divers.


v/r

Jan

Remember to relax, mind your trim, & insure the dam zipper is completely closed before entering!


Best Fishes,
DSD

 

[W3tWilly]

I always do a couple of practice self righting somersaults at the beginning of my dives in drysuits. Keeps it fresh in your mind plus I enjoy doing them. I imagine to those not use to diving in a drysuit or the techniques it might look a little awkward, but who cares im having fun while I dive.

 

[DA Aquamaster]

Use the suit for bouyancy at least initially. The whole "use the wing for bouyancy" applies to technical situations and indeed is essential with doubles, stage bottles etc, due to the larger swing weight of gas and the potential for much more negative bouyancy with stage, can lights, reels, etc.

What is important in a single tank situation is to not be over weighted. As long as you are neutral with only enough air in the suit to be comfortable (as in not excessively squeezed) at the end of the dive with 500 psi in the tank, the etra weight from the 4-5 more pounds of negative bouyancy caused by a full tank willnot be a problem if your suit fits correctly.

When you gain experience, you will learn a few things. Like:

1. If you need to go into a head down position, dumping gas from the suit and adding it to the wing or BC instead to maintain neurtral bouyancy can help by preventing all that gas from rushing to your feet.

2. The suit requires a minimum amount of gas to loft the insulation and if you do not use enough gas in the suit, you will be cold.

3. Too much gas in the suit just makes it harder to control as that big bubble moves excessively and expands and contracts excessively even with small changes in depth.

4. Happy dry suit diving is a balance of having just enough gas to loft the insulation while maintaining a very slightly snug yet comfortable and unsqeezed feel in the suit.

5. Over time you will almost certainly find yourself gravitating to using the wing or BC for "extra" gas required to maintain bouyancy once you get a feel for diving the suit.


Giant strides are a non issue unless your neck seal is excesivley use. I have literally hundreds of giant stride dry suit entries off boats, some with a 4-6 ft drop to the water and it has never been an issue.

You want the neck seal to feel slightly tight - short of choking you, but if it feels comfortable it is borderline too loose. Trim slowly in small stages and understand on the surface that they feel looser in the water with gas in the suit.

 

[Ber Rabbit]

1. What are the advantages/disadvantages/recommendations you have for bouyancy control and dry suits?

Personally I keep enough air in the suit to be warm and do the rest of my buoyancy control with my BC. I had some scary experiences with uncontrolled ascents while learning to dive dry. My drysuit was a little big and the dump valve was on the inside of my bicep making it incredibly hard to dump air. There was a time when I was too afraid of the suit to put ANY air in it.

I dump most of the air from my BC before I start my ascent so I only have to mess with dumping my (new, nice fitting) drysuit as I ascend. When I'm diving shallow I only use the drysuit because once I have enough air to be warm I'm usually neutral so I don't need air in the BC. Uncle Pug had a nice post somewhere that mentioned the "20 foot squeeze" as a starting point. Drop to 20 feet without adding air and see what that feels like, try to maintain that feeling throughout the dive by adding/dumping air. Tweak as necessary for your comfort level. Over time you will find what method allows you to control your ascent while making you happy, that's the method you should use.

2. Undergarments. My question is whether I am using the right logic in layering. Suggestions?

Layering is good! One thing that was never mentioned to me when I was training that wasn't fun to find out the hard way is that drysuits can "bite". I was told they could squeeze; my old suit removed a chunk of skin from my knee and left me bleeding when my undergarments (sweats I believe) weren't thick enough. THAT is NOT a squeeze, it's a BITE! Oh and females should avoid regular bras, especially underwire ones. Wear a sports bra or a bathing suit top, this is NOT something you want to learn the hard way...been there, done that :11:

3. Giant Strides. Doing a shore entry over the weekend, so this will not be a factor. However, I've been thinking through this and don't quite understand how you can do a giant stride entry without running the risk of blowing out your wrist/neck seals as you hit the water. Even with crouching before entry to vent out excess air will likely not prevent additional air from being pushed out on entry. My question quite simply is: How do you do this in a dry suit?

I dump my BC (wearing a single tank) and do a normal giant stride with my dump valve in the auto dump position. I've never had an issue with my new suit burping through the neck. My old suit would but that's because it didn't fit properly. I come up afer the entry looking a bit like the Sta-Puff Marshmallow man and then give myself a hug to finish dumping the suit.

4. Misc advice. Any and all suggestions on what I should try, practice, attempt during my dives is more than appreciated. I"m planning to do another dive or two after the official 2 dives of the course to blow more bubbles and continue to practice. Your advice on anything relating to diving a dry suit is most appreciated.

v/r

Jan

If you have suspended platforms available you can practice skills under them. It's nice because you know you have something to stop you from shooting to the surface while you're practicing a skill you may not be particularly good at. I practiced under platforms and beside ascent lines for quite a while.

Have fun! May you be one of those people who take to it immediately and have no problems!
Ber :lilbunny:

 

[tstormdiver]

Remember to relax, mind your trim, & insure the dam zipper is completely closed before entering!


Best Fishes,
DSD

Here! Here! I second that one! I've done that one a couple of times. I thought I had it zipped all the way,..... Well, let's just say that it's no fun when you're trying to dive 40 degree water in Jan. with your zipper leaking. As for what to use for buoyancy, for now do as you are taught until you are completely comfortable then try some different methods, you may find one works better for you than the other. I was also originally taught to use the drysuit for buoyancy. As I am preparing to go into technical diving, I started to use the drysuit less & less for buoyancy control. It is a little trickier, but doable. Now I dive the suit with a considerable amount of squeeze (probably more squeeze than most other people like). As long as I can move reasonably, & can breathe with relative ease, then that's all the air I add to it. As for preventing blowing the neck seal during a giant stride entry, during the summer months, I will wade out into the water right after donning & zipping the suit up & take a real quick dip. This does 2 things for me. First it cools me off long enough for me to get into my gear & second,it does a thorough job of "burping" the suit. If it's too cold to do that, then I just do the "crouch method" & that seems sufficient.

 

[spectrum]

JanR,

Consider this class to be like any other scuba learning experience. There will be different ways of doing things and you need to be prepared to make some decisions and maybe even filter some BS.

Suggesting that you use the drysuit as the prime source of buoyancy invites every drysuit diving nightmare imaginable. Like some others have said I run only enough suit air to control squeeze and enable loft.

Remember that a drysuit cannot begin to vent air as fast as a BC. Loading the suit with air opens the door to loosing control.

Good garment materials are designed to be incompressible so they only need a little relief to work. Wearing the wicking layer (Under Armor /polypro) is essential for at least 2 reasons. First it will get perspiration away from you so you can be warm and dry. You can expel a LOT of water during a dive. Second, it keeps you body oils away from your garment. Laundering is not your garments friend. Bathe and wear a clean wicking layer to avoid needless washing.

Consider wearing a DUI type weight harness. In a drysuit a weight belt may not have a good bite on your padded hips. Loosing a weight belt in a drysuit is not a pretty thing. It also lets you wear your lead a little lower than your hips will provide. For some diver suit combinations this can eliminate floaty feet and the need for ankle weights.

It's a fairly easy transition to diving dry though it may take a few iterations to get thigs trimmed out just right. 10-20 dives usually has divers back to where they were in a wetsuit.

Pete

 

[tstormdiver]

Layering is good! One thing that was never mentioned to me when I was training that wasn't fun to find out the hard way is that drysuits can "bite". I was told they could squeeze; my old suit removed a chunk of skin from my knee and left me bleeding when my undergarments (sweats I believe) weren't thick enough. THAT is NOT a squeeze, it's a BITE! Oh and females should avoid regular bras, especially underwire ones. Wear a sports bra or a bathing suit top, this is NOT something you want to learn the hard way...been there, done that :11:
Ber :lilbunny:

I can't say I've ever had my suit remove any skin, but I have had it squeeze me hard enough a couple of times to cause some definite bruising around my shoulders & upper chest (forgot to hook up drysuit hose until I reached about 30 ft). I fixed that reeeeal quick! The worst, though, was when I got into an uncontrolled descent to 90ft, the first time I dove my doubles. I got so task over loaded trying to stop or slow myself & equalize my ears fast enough, I really didn't have time to worry about the drysuit. As for the "bra" issue, I only wear sports bra anyway, but can see where you're coming from. That would hurt:11:.