Do you remember?

[ckharlan66]

Do You remember the first time you really had perfect neutral bouyancy?

I just got it for the first time on my trip to Ft. Lauderdale. It was great I didn't have to keep making adjustments I just got to enjoy the dive and have fun without having to worry about adding or subtracting air.

I am looking forward to hearing your stories.

Chad

 

[scubagatorgal]

in enjoyment level! Did you make any changes in your weight or did this result from more experience with your breathing?

 

[ckharlan66]

More experience plus a lucky WAG from the DM in regards to wieght because I was diving with different exposure protection than normal and it was my first dive in salt water.

I normally am pretty close to having it nailed but I have to fiddle with it a little. Hopefully I won't have to mess with it as much now. I just have to keep up the practice.

Chad

 

[Bob3]

Good point there, 'gatorgal.
The "average" adult has a lung capacity of about 6 liters, which translates into a little over 13 lbs of buoyancy. If you swing only half of that from inhale to exhale, that's a difference of over 6½ lbs. Breath control is the key for the fine tuning of buoyancy.

 

[scubagatorgal]

DM's jump in here at any time but the main reason new divers have so much problem mastering buoyancy is because they are overweighted. As nervousness increases newbie breathing and changes their "normal" buoyancy they usually are by necessity overweighted in those beginning and sometimes exasperating first attempts at scuba and descending. When buoyancy seems so difficult the student stresses slightly breathing harder so he dumps, sinks, adds air, dumps, adds and the tank is wiped quickly. As the student gets more confident and controls his breathing pattern he can attempt to lose some of the weight and between breathing normally and weighted properly it all falls into place...just not effortlessly or without practice.

I have found the best way for divers to find their ideal weight is to figure it out at about 15-20 ft with 1000 psi. After a dive is a great time because you should be breathing pretty normal by this time. Adjusting 1-2 pounds at a time until it is precision tuned and you can stay suspended horizontally or vertically without any effort. Personally I have adjusted my weight as much as a half pound by dumping shot out of a soft pack...but I HATE weight!

Of course your ideal weight changes with wetsuit changes, salt to fresh, carrying extra gear including floaty camera's or heavy tek stuff and the dreaded increased personal weight gain...

It is so worthwhile to work on this skill and take classes to fine tune buoyancy.

 

[jonnythan]

Originally posted by Bob3
Good point there, 'gatorgal.
The "average" adult has a lung capacity of about 6 liters, which translates into a little over 13 lbs of buoyancy. If you swing only half of that from inhale to exhale, that's a difference of over 6½ lbs. Breath control is the key for the fine tuning of buoyancy.

Can't argue with you about the breath control, but just because I'm kinda into this stuff, I wanna point out that even though lung volume is about 6 liters for the average adult, that's not the whole story.

The lungs have a minimum volume that can never be exhaled.. this volume is necessary for the alveoli not to collapse due to the fact that they're fluid lined. This is called residual volume and is around 2 liters.

The difference between a regular exhalation and a total exhalation is called the expiratory reserve volume and is about 1 liter.

A *regular breath* has a volume of about 2 liters.

The difference between a regular inhalation and complete inhalation is the inspiratory reserve and is about 1 liter.

Total: about 6 liters, the maximum breath (as much as you can inhale to as much as you can exhale)is usually a bit less than 4 liters (that's the vital capacity). People generally only find it comfortable to breathe within the normal 1.5 to 2 liter breath range... take small breaths at high lung capacity or low lung capacity and your lungs will start to hurt, or take full 4 liter breaths and your head will start to hurt.

So, even though breath control is important, no one has to worry about their weight swinging up and down by 6.5 pounds while breathing

Wasn't that EXCITING?

 

[Uncle Pug]

No.


Now for an interesting tid bit... applicable to those who donate the regulator they are breathing from to an OOA diver:

When handing off the long hose to an OOA buddy it is tempting to take a bigger than normal breath before giving it up...

This has the immediate effect of sending the donor up... and of course since the OOA donee sees his/her air source going up the temptation for him/her is to get a big first breath in case the supply goes bye bye. So up goes the donee as well.

Now both divers have a positive buoyancy problem and are on their way to an uncontrolled ascent if this is not corrected right away.

Moral of the story:
When donating your long hose resist the temptation to suck a big one before giving it up. You always have the backup under your chin and you won't die immediately when the primary is removed from your mouth.

 

[Fishkiller]

Originally posted by Uncle Pug

you won't die immediately when the primary is removed from your mouth.

now what is better? completly exhaling on every breathe or holding the inhale a little longer???

 

[Uncle Pug]

Originally posted by Fishkiller
now what is better? completly exhaling on every breathe or holding the inhale a little longer???

Are you talking before donating or just normal uw breathing.. or what????

 

[Fishkiller]

you never know the exact moment that your buddy will grab your hose away...

so the question goes to normal UW breathing as you would be in a calm relaxed state

then

in good warm clear water...