How do I control my bouyancy and trim?

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uses is no Jedi stuff. He is using his lungs and you can use them too (yours, not his :) )
How?
You can use your lungs effectively only if you reached good buoyancy, which is not a secret thing or something that cannot be mastered, just a matter of practice and experience.

Lets assume that you are neutral buoyant at a certain depth. When you inhale you'll rise up a little, when you exhale you'll sink back. That's all. It is the same as if you removed (or added) a small quantity of air from your BC, but you can control it with more accuracy (although our lung's volume are about 5 liters we never completely empty or fill them). You can use it in order to make small depth corrections and you can't avoid it anyway since you'll be breathing anyway during all your dive. You don't have to hold your breath to rise up a few inches, just alter a little your breathing, a few more seconds before exhaling (or inhaling). If you need to go up (or down) several meters you don't use your lungs for that.

If you are not neutral buoyant, it won't work and anyway you'll have to keep in constant motion to keep yourself in the same depth which is not so good.

Don't carry excessive weights, it makes buyancy controlling more difficult.
 
You are on the right track. If you lose a weight or even use less weight the amount of oxygen in your lungs can be used to keep you bouyant. I have been diving for 16 years and weigh 220lbs. all i use is 12lbs of weight to keep me down the rest i mediate with how much and/or how deep i breath. Find the medium, with your breathing once you have regulated your bouyance leave that amount of air in your lungs and just breath the amount of air you need.


:cool:
 
Originally posted by smkscrn
...the amount of oxygen in your lungs can be used to keep you bouyant
But only if you're 20 feet deep or less. :grad:

Roak
 
20 feet

thats snorkeling

filling my lungs works great in cave diviving

@ 80-100 feet once your down I dont realize it, but i do the same thing.

Habit i guess :rolleyes:
 
Originally posted by smkscrn
20 feet

thats snorkeling

filling my lungs works great in cave diviving

@ 80-100 feet once your down I dont realize it, but i do the same thing.

Habit i guess :rolleyes:
Woosh.

I was poking at you using the word "oxygen" rather than "air" or "gas."

You're not going to be doing any buoyancy control at 80-100 feet if you're on oxygen, you're going to be dead.

Roak
 
I have my entire Venture Crew trained to all yell out "But we don't dive on oxygen" if anyone makes that mistake. I do make a point of purposely slipping up just for the entertainment aspect of it all.
 
Hi Uncle Pug,
Thanks for your advice. You are right, I am not light in the feet. Fastening the bcd higher on the tank has solved the trim problem.
 
Originally posted by Uncle Pug

Now another thing that will help your buoyancy control immensely... in fact I consider it THE key... keep as much gas out of your suit as possible. Use the proper undergarment to keep warm... use argon if you must... but keep at least a 20' squeeze on the suit. (Don't be like Nate & Christy though and take it to the extreme - 65' squeeze and suit hickies all over.)

Hey, I resemble that remark. :wink:

Seriously though, I just downloaded my dive profile from last week's dive with UP (I was on a business trip all last week and finally got caught up at home and had time to fill out my log), and I noticed that my last dive I used the least amount of gas. I think it was because on that dive I ventured to let in a little bit of gas (more than on any other dive), so I wasn't working so hard to stay warm.

The worst that can happen if you use too little gas it suit hickies (they *are* nasty looking, but didn't hurt at all), but the worst that can happen if you've got too much gas is messed up buoyancy and an out of control ascent.

Given the choice between the two, I'll choose hickies any day.


Nate
 
Originally posted by newton
Given the choice between the two, I'll choose hickies any day.
Hey buddy.... glad to have you back!
And I'm thinkin' that maaaaybe you kinda like those hickies....
Hmmmmmm?
 
Originally posted by GeekDiver
I want to dive Texas Flower Gardens in a few months and don’t want to have to stay 5-6 ft above the bottom out of fear that I will crash into the bottom. That’s the reason I need to improve on this.

I beg to differ...

First of all, as I can tell you from experience, if you decide to stay on the bottom, you will miss much of what the flower gardens has to offer. I always prefer to stay at least 10-15 feet from the bottom to give myself a wider view then drop down to those things that interest me the most. Some portions of it can be like a 'coral maze' and if you end up close to the bottom you will just be like a rat running from one corridor to the next.

Secondly, there are sooooo many more reason that provide a more pressing 'need' to improve on bouyancy, but the important fact here is that you WANT to learn and WANT to improve. Wanting is the first step to doing.

Enjoy your trip to the flower gardens, they are fabulous (esp. compared to the usual Tx diving)

Dive often, but dive safe

John
 
https://www.shearwater.com/products/swift/

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