buoyancy

[marpac]

what's the best way to improve on buoyancy. any thoughts or is it just log the dive time and practice practice practice.
I'm looking for ways to improve

[Akimbo]

Please let me know if you find this post useful:

Minimum Diving Weight

[BobSch]

One important factor is that your lungs can turn into a BC so just remember to let out as much air from your lungs as you can and try shollower breaths. This of course one of many possiblities but can be over seen and forgotten. Enjoy and diving should be relaxing.
Remember Take only pictures leave only bubbles!
R. Schneider

[PfcAJ]

Get your weighting right, and dive dive dive, then dive some more. Try to ween yourself off of holding on to ropes/ lines when ascending too.

[herman]

Get rid of your BC and learn to dive without it. Buoyancy is all about proper weighting and learning to use your lungs as real time buoyancy compensators. For whatever reason, most divers have forgotten...or more likely were never taught, it is a buoyancy COMPENSATOR, not an add air to make me neutral with a lot of extra weight compensator. I know most don't want to do away with the BC so instead try diving with no air at all in the BC. This will require you to get your weights dead on and to learn the proper use of your lungs. You will be amazed at how easy buoyancy control becomes once you get your weighting adjusted correctly and learn how to use you lungs instead of pumping air into your BC to compensate for poor weighting. While you are thinking about this, what should your BC actually be compensating for anyway? In normal rec diving, tank buoyancy changes from air use and wetsuit compression are the only things that change in buoyancy and consequently are the only things that the BC should have to compensate for. Tank variance is only in the 4 lb range and is easily handled with lung volume alone, wetsuits vary from none to a good many pounds and may require some diving techniques not taught today or in the case of very thick wetsuits may actually require the limited use of a BC. Wetsuit compression varies greatly with different wet suits and has to be dealt with on an individual suit and dive basis. Tech diving with large tanks and a lot of required gear is a different discussion.

Learn to use the BC for what it is intended for, buoyancy COMPENSATION, get rid of all unneeded weight and learn to not rely on the BC to cover for poor diving practices. There are a couple of recent threads on no BC diving, do a search and read the post, you will find a lot of good information in them.

[Akimbo]

Get rid of your BC and learn to dive without it. Buoyancy is all about proper weighting and learning to use your lungs as real time buoyancy compensators. For whatever reason, most divers have forgotten...or more likely were never taught, it is a buoyancy COMPENSATOR, not an add air to make me neutral with a lot of extra weight compensator...

Well stated. Unfortunately it is a lot harder to go without a BC while wearing a wetsuit made from Neoprene blended materials that dominate the market now. These materials are much more flexible and comfortable than the older Rubatex suits, but are also much lighter in weight and more compressible. The weight change from the surface to 60' on my full 7mm farmer can be in the 12 Lb range where my old Rubatex suit was closer to 3 Lbs. The new material is warmer on the surface, but I estimate that I am as cold at 50' as I was at 150' in the Rubatex suit.

Aside from being less expensive, the flexibility of new materials allows off-the-rack suits to fit far better. It is unfortunate they perform so poorly at depth.

[herman]

Very true, which is the reason I included the part about maybe needing to use a BC when diving a thick wet suit. As you know, there are old school ways to deal with it but for those times a BC is the easiest way and then it is being used as it should be, to compensate for buoyancy change.

[TSandM]

marpac, what kind of buoyancy problems are you having?

Good buoyancy begins with proper weighting. If you are underweighted, you have problems staying down. If you are overweighted, you carry too much gas in your BC (to "compensate" for the extra lead) and that makes you very unstable, since that large bubble expands and contracts with depth changes. So doing a formal weight check with a near-empty tank is the first step to improvement.

Once you are correctly weighted, you can address your posture in the water. If you are diving head up and feet down, then every time you kick, you are trying to push yourself upwards. The only way to avoid ascending is to keep yourself negative (not put enough gas in your BC to compensate for your lead and gas). That means that, if you are distracted and stop finning, you will sink. Achieving a horizontal position makes you much more stable in the water, because now you can be truly neutral.

Buoyancy issues on ascent are often a combination of problems. Too much gas (from overweighting), a failure to anticipate the need to adjust your buoyancy before you have lost control, and apprehension leading to a change in breathing pattern can all contribute to issues while ascending. I try to tell students, when they are too novice to FEEL the changes, to watch their depth gauge -- if the numbers are getting smaller, they are going to need to vent SOMETHING!

Remember that the easiest BC you can vent is your lungs; when you feel yourself getting light, the first thing to do is EXHALE. That buys you time to adjust your BC (or dry suit).

Anyway -- those are some general ideas; if you tell us what your specific problems are, we might have some additional tips.

[Dyno Bill]

I agree that using you own natural skills to control buoyancy trim is a skill that has been evolving for a long time. Kind of like old fashioned carburators on a car compared to fuel injection of today. The ability to dive without or at least a small amount of help using a balder of some sort to make basic adjustments is what we all strive for. My opinion after freediving for years the use of a tank is an extra burden that is a waste, but some insist there is a benefit to the use of an air supply under water. I have given a lot of thought to the subject and it seems advising a new diver to leave the BC in the boat is like advising someone to leave the seat belt unhooked for the pleasure of being free and of course there is the dreaded motorcycle helmet. When I started diving we used a horse collar that you could orally inflate should you need flotation at the surface. I would recommend that divers work to become less dependent on equipment but in actuality most seem to love the goodies hanging all over them. I watched a utube video the other day of a diver in a kelp forest diving a dry suit carrying three tanks and god knows what all else he was hauling but to be in midwater in a kelp forest he might have been at 50 fsw give or take moving like a used car lot. The less we depend on stuff the easier and more efficient we are but in some cases the more vulnerable we also become so my advice would be to dive what you have been taught and work to get better at trim and air consumption and for gosh sakes do some navigation. More folks get lost quicker than you might imagine. But I don't give advice to people I havn't been in the water with.
Bill

[rk288]

My limited experience compared to the other posters here has taught me that proper weighting and breathing plus trim adjustments are the key to great buoyancy control.
Had a night dive this year where I ended up in 3 ft of water with 110 lbs left in an AL80. I asked my Instructor who also taught me Peak Buoyancy how I did that...she said your'e getting better at this.