Not Enough Weight?

[AZNetEng]

You might have an air pocket in your BCD but likely being a new diver the variable is the air in your lungs.

 

[TMHeimer]

I agree that it may just be getting used to adding and venting tiny bits of BC air. That was a big point our instructor kept hammering at when I took OW. But, that may not be the problem too.

 

[Neilwood]

I suspect that the "sink like a rock or start ascending" sounds like you are adding too much air when you press the button on your inflater.

What you should be trying to do is slowly adjust your buoyancy on the way down and back up. As you descend, your wetsuit(?) loses buoyancy so you will have the tendency to descend quicker. A small squirt of air will slow the descent rate down (by small I mean 1/4-1/2 sec presses). What you want at the bottom is to be slowed right down prior to hitting bottom - at this point you should be able to manage your buoyancy by breathing. Bear in mind though that buoyancy control comes with a delay between the adjustment and its effect. It might take a second or so for your inhalation to start moving you upwards and the same goes for exhalation (it might take a second or so to start dropping).

 

[RonMurray]

This sounds like a classic case of overweighting. The physics do not change from the surface to 60'. That is to say, if you can descend from the surface, you do not need any additional weight. You are only going to be become more negatively buoyant as you descend (ignoring changes due to air consumption). You are not going to become suddenly positively buoyant 3' from the bottom unless you do it with your lungs - our your BCD. In my mind there is no question that there is air in your BCD, and given the problems you describe, there is a lot more air in there than you think and that is why it is difficult to manage.

Do a weight check on the surface, eliminate weight until you can float at eye level with an empty BCD holding a "normal" breath. At that point, when you then exhale you will sink, and become more negative as you continue to descend (and you descent rate will increase). You will then need to add very small amounts of air to your BCD to slow and finally arrest your descent.

I recommend practicing descending as slowly as possible. This will keep you from having to add a large amount of air, probably too much, to keep from landing on the bottom. I teach my students to never touch the bottom on a descent.

Good luck, once you get it - and you will - it is the closest to Zero-G you will ever be. Coolest thing ever.

 

[ouichef]

Thanks everyone! these are some great things to look at. I'm not taking the time (when diving) I need to work on buoyancy, period. I am seriously thinking about taking the buoyancy class. It will afford me the TIME to work on it without the distractions of OW cool stuff.
A few things:
Yes, I'm doing the SS and its not always easy.
When I vented the BCD, I was totally horizontal each time, the DM just were like "hmm that's strange" My OW instructor worked with me a little and it helped.
Your correct, my breathing is pretty controlled BUT this is a different sport and adjustments do have to be made.
Most of the time these things happen but not ALL the time, there are those moments when I say to myself "THIS is way it should be" and I love it.
It really doesn't help that 50% of the time I'm totally chilled and the other 50% I have no patience and really get frustrated, especially with myself lol
Practice, practice, practice and when I got it.....practice some more

 

[Tralfamadore]

Thanks everyone! these are some great things to look at. I'm not taking the time (when diving) I need to work on buoyancy, period. I am seriously thinking about taking the buoyancy class. It will afford me the TIME to work on it without the distractions of OW cool stuff.
A few things:
Yes, I'm doing the SS and its not always easy.
When I vented the BCD, I was totally horizontal each time, the DM just were like "hmm that's strange" My OW instructor worked with me a little and it helped.
Your correct, my breathing is pretty controlled BUT this is a different sport and adjustments do have to be made.
Most of the time these things happen but not ALL the time, there are those moments when I say to myself "THIS is way it should be" and I love it.
It really doesn't help that 50% of the time I'm totally chilled and the other 50% I have no patience and really get frustrated, especially with myself lol
Practice, practice, practice and when I got it.....practice some more

You're saying you were horizontal when venting. When doing this were you using your corrugated hose or your kidney pull dumps by slightly raising your backside and lowering your head?


I took the peak performance buoyancy specialty when I did my AOW and although it was loads of fun it doesn't do much to actually help your buoyancy. From what I recall the skills involved for myself were a short hover and some fun stuff like swimming through hula hoops. Go ahead and take it as part of your AOW but it's definitely no supplement for just getting in the water and diving. There's no better feeling than being really dialed in with your buoyancy. Everything else seemingly just falls into place afterwards. It will come with time like everyone else.

 

[NYCNaiad]

Thanks everyone! these are some great things to look at. I'm not taking the time (when diving) I need to work on buoyancy, period. I am seriously thinking about taking the buoyancy class. It will afford me the TIME to work on it without the distractions of OW cool stuff.
A few things:
Yes, I'm doing the SS and its not always easy.
When I vented the BCD, I was totally horizontal each time, the DM just were like "hmm that's strange" My OW instructor worked with me a little and it helped.
Your correct, my breathing is pretty controlled BUT this is a different sport and adjustments do have to be made.
Most of the time these things happen but not ALL the time, there are those moments when I say to myself "THIS is way it should be" and I love it.
It really doesn't help that 50% of the time I'm totally chilled and the other 50% I have no patience and really get frustrated, especially with myself lol
Practice, practice, practice and when I got it.....practice some more

If you were totally horizontal each time, then the air is definitely still caught up in your bcd. (The same thing can also be true if you were vertical as well if the air was trapped on the opposite shoulder of where your inflator hose is.) Think of a rectangular box filled with water & a small air bubble inside. If the box perfectly level, the air bubble will likely go towards the middle of the box. The only way to ensure that the air bubble goes to the location you want it to is to angle the box.

If you think of you/your bcd as that box, it becomes more clear that you need to angle your body/bcd while choosing the right location on your bcd to vent your air. (Even more so because your bcd has a lot more nooks & crannies than a rectangular box.)

• Try putting your head down a little & your hip up a little on the bottom dump valve side while using that dump valve.
• Or try putting your head up a bit & angling your shoulder up on the same side that your inflator hose is.

I think a good buoyancy class can work well if it's truly a good buoyancy class & especially if it's one-on-one with an instructor.

Most divers feel the same way you do at first. A lot of those feelings are resolved by time & lots of diving. I think most divers fall into somewhere in the newbie category till they have over 50 dives.

 

[Neilwood]

One thing that will help is, if possible get a friend to video you underwater. That will serve two purposes - 1) it will confirm what air is actually in your BCD and 2) how effectively you are adding/venting air.

1 is important because you might think it is empty when there is actually air left in it
2 is important because you can see how effectively you are at actually adding/ removing air. It is very easy to not have the dump in the best place (whether it is the hose, shoulder or butt dump). That might get rid of some air but not all of it.

 

[ouichef]

Sorry guys I meant VERTICAL. Straight up/down

 

[NYCNaiad]

Sorry guys I meant VERTICAL. Straight up/down

Right, but as I said above, even completely vertical you still need to hitch up a shoulder & choose the right valve to exhaust your air through. Try my ideas above about positioning yourself and/or @Neilwood's idea re: the video. Bet you'll be surprised.