Question re: buoyancy

[VanGirl]

Hi...As a newbie diver with only 7 dives under my weight-belt thus far (and a new drysuit cert. in hand...) I have a question re: buoyancy & a scuba-fear. I find that I still rely a bit on the "bottom" and while I'm pretty good at not touching down more than a carefully placed hand I still do technically I guess 'hit bottom'. So when it comes to things like making my safety stops at 15' I have a little trouble staying at 15 and not bobbing up or conversely head back down. This was especially hard this weekend in my drysuit using just it for my buoyancy control...
This whole 'not being able to hover at a certain level/depth' is a bit of a concern. Especially if the bottom is further down than I'd like to be.... :errrr: How did folks here get the solid knack for this hovering thing...and has anyone else ever had the fear of 'going too far' down..... I mean logically I know that I can avoid going too far down via my suit, BCD, weight ditching if absolutely necessary... So I'm not certain why this thought still sorta bugs me.
Any advice is always welcome.
Happy Diving!

 

[Michael Schlink]

I don't reccomend using your drysuit for bouyancy adjustments. I would suggest that you use your BC for adjustmenst and only put enough air in your suit to keep it "comfortable". As far as getting nuetral that usually takes time and practice, although you should be able to get awfully close by now. You will be able to fine tune your skills with more experience and practice. practice a horizontal hover on your safety stops until you can do it without any real effort or concentration.-M

 

[jonnythan]

You will get better, no worries. Just keep working on it. If you try to keep yourself horizontal in the water and focus on maintaining your buoyancy while *not moving at all*, it'll come.

 

[VanGirl]

Thanks for the encouragement...and the tips!! My own inclination was to use my BCD for buoyancy control when diving dry. But my instruction, in true PADI style, stressed "suit only" at depth. I figured I was missing something if I didn't get a firm grip on "all suit buoyancy control". The day I can master hovering at 15' will be
G-L-Orio-US!!
Cheers & Happy Diving!!

 

[jonnythan]

There's a lot of stuff on the boards here about using your BC for buoyancy instead of your drysuit. Personally, I think it's a great idea. Dealing with a relatively large bubble of air in your suit is not good. Having that large bubble in your suit also creates a less stable buoyancy issue since there will be a greater buoyancy change per foot you go up.

 

[VanGirl]

Cheers Ya...I've been reading a good thread on the whole suit vs BCD debate. Seems the concensus is on using your BCD. I'll definitely have to master this hovering thing before I decide to go deeper. And it seems I might have been overweighted a titch this weekend... My first stop once the gear was hung up was to log on here to see what I could learn. Y'all are awesome!
Happy Diving! :bouncesbl

 

[MXGratefulDiver]

Remember that you can use your "other BCD" for bouyancy control as well ... the one you were born with.

Proper breathing is key to good buoyancy control ... especially at shallower depths.

In another thread you said you're wearing 37 lbs of weight (actually, from the description it sounds like you meant to say 34 lbs). If you are overweighted, you have to compensate with extra air in your BCD and/or drysuit. That makes it more difficult to maintain good buoyancy control as you ascend to shallower depths because all that air expands ... sometimes to the point where it's difficult to let it out fast enough to avoid popping to the surface. This is a fairly common problem with newer divers.

Some things to work on then would include ...

- Do the weight check I described in the other thread, and eliminate as much weight as possible to maintain a hover in 10 feet of water.

- Working on using your breathing to control buoyancy. If you start to rise, breathe out. Then as you have to breathe in again, let a little air out of your BCD to maintain position. If you're starting to sink, breathe in ... then as you breathe out, add air (in very short bursts) to your BCD to maintain position.

- Use your BCD sparingly ... and add or remove air in short bursts. Remember that it takes a couple of seconds for the change in buoyancy to become apparent. Many new divers tend to overuse their inflator buttons, which results in "taking the elevator" a lot. Add or vent air in small increments.

- Work on improving your "awareness" of when you need to add or vent air ... often a newer diver will wait till they're already on the ascent to even find their inflator hose. You know about Boyle's Law ... so it only makes sense that when you're coming upslope you should have your inflator hose in hand, ready to vent as soon as you feel yourself starting to get positive. Waiting too long means you're starting to rise. Then the air in your BCD is expanding even while you're trying to vent. If you wait too long, it's a game of "catchup" that usually results in overreacting ... then you'll bounce off the bottom because you let out too much air trying to stop ... inflate too much causing you to rise ... deflate too much, etc. It's a very common phenomenon while you're learning.

Proper breathing, awareness, and using the inflator in small increments is the key to good buoyancy control.

Hope that helps ...

... Bob (Grateful Diver)

 

[VanGirl]

It all helps a ton!! Thanks. I can't wait to get back at it to keep learning. Gotta say despite the freezing fingers and 'mile' long hikes to the dive site with a 'million' pounds o' gear on.... I love the sport & look forward to new challenges.

 

[theskull]

All good responses so far. Buoyancy is an art and needs constant attention and practice. A couple more tips for you:

For right now:
1. Make your ascents along a wall, sloping bottom, or ascent line. This will give you a visual reference to help control your buoyancy AND something to grab if you do need a little help.
2. Dive often, and with divers who have great buoyancy control. You will learn alot from watching and emulating, and they will offer tips if they know you are seeking to improve.

For skill development:
1. Perfect buoyancy is most difficult to maintain at shallow depths, so practice swimming just off the bottom in 5-10 ft. of water--pool or open water, doesn't matter.
2. Attempt to maintain very strict control. Make it a goal to swim exactly 3 feet off the bottom, or to ascend at exactly 30 feet per minute, or to make your safety stop at exactly 17 feet. If your goal is very specific, you will be in great shape if you vary by a little bit. However, if your goal is to make a safety stop around 15-20 feet, you will not be developing your skills.
3. Safety stops are an excellent place to practice your buoyancy control. If you are using an ascent line, stay close enough to grab it if needed, but make it a goal to just "stick" at the desired depth exactly. . . without kicking. . . without sculling. . . without adjusting your BC after getting it right once. . . by using the quantity and rhythm of your breathing to stay right where you want to be.
4. NEVER descend to the bottom! Descend to just short of the bottom, controlling your BC so that you come to a gentle stop a few feet off the bottom without having to kick so you don't stir up the bottom.

You have a great attitude and will surely master this in short order.

theskull

 

[diverbrian]

Some of us who get cold easily wind up using the drysuit for buoyancy control "without intentionally doing it." I personally wind up bleeding some (not much) air from my BC at depth to add it to my drysuit to fluff the undergarments a bit. When the undergarments are compressed they tend to lose a little insulation value :ice:.

So, I wind up venting my drysuit before my final ascent and using my lungs and BC to control my buoyancy at stops. But, I still have an appreciable amount of air in my drysuit at depth that must be accounted for.