Buoyancy help

[IowaDiver]

My husband and I have both logged in about 13 dives. We have begun our AOW because we were told that it would help our buoyancy. I can't seem to get it undercontrol. I seem to be on the bottom (20' down) or on the top. I've tried adding a bit more weight. I've been told to just keep practicing. My questions are:
What are some secrets that will help me get this under control? It's frustrating to both of us.
Am I ready to try deeper dives if I don't have this under control?

 

[MikeFerrara]

The AOW class is where you do things like your first deep dive, navigation, ect. My recommendation is to run from any instructor who wants to take you deep before you have a handle on basic skills. Navigation is pretty hard without decent buoyancy control too.

Practicing will make for slow progress if you're practicing it wrong.

It's more likely that you have too much weight than too little.

Aside from having the right amount of weight you need to have it in the right places for balance. you need to have correct body position and control and combined with the right amount of weight in the right places combines for good trim.

Try some searches. There are tons of posts on this board that explain this in detail as should have been done in your entry level traiing.

you might also consider pointing your instructor tho the board ao he/she can get it figured out too.

 

[beachdivequeenbelam]

My husband and I have both logged in about 13 dives. We have begun our AOW because we were told that it would help our buoyancy. I can't seem to get it undercontrol. I seem to be on the bottom (20' down) or on the top. I've tried adding a bit more weight. I've been told to just keep practicing. My questions are:
What are some secrets that will help me get this under control? It's frustrating to both of us.
Am I ready to try deeper dives if I don't have this under control?

One cool game my husband and I came up with for helping with kids during OW and AOW is
1) get down about 15 feet on a platform(rock quarries are good for this) overweight yourself
2) Lay down on the platform face down
3) Breath in and see how you rise and breath out and see how you sink
4) the contest is to see who can do this the slowest and with the most control over speed
5) Once you establish this pattern, you can take off a pound at a time until doing the exercise you start to float.

I used to use up to 27 lbs when I only had 7-15 dives. I came up with this during Rescue Training so I didn't have to use my LP inflator hose so much. I use 4- 6 lbs depending so my tank.

It is really cool when I am in the crusher houses at these quarries I dive in to use my lungs to move inside the wreak area rather than messing up the viz by kicking around a lot

 

[Jason B]

I'm with mike, buoyancy control is the cornerstone to all other diving activities...navigation, photography, etc...

 

[Uncle Pug]

You don't need help with your buoyancy... you need help with your buoyancy control. This is an important distinction.

First there is a difference between static neutral buoyancy and dynamic buoyancy control. You can achieve perfect neutral buoyancy only to have it *disappear* the moment you start moving. Since most divers are constantly moving they never really know if they are neutrally bouyant or not because of the dynamic forces effecting them as they move through the water.

Secondly trim (body position in the water) plays a critical role in dynamic buoyancy control. At the base level understand that when you move forward through the water at the typical heads up body inclined up trim a lifting force is being generated. Your body is like an airplane wing moving through the water. To counter this upward lifting force most divers will be carrying extra weight. When they stop moving forward the lift is lost and they sink. They have the choice of adding air to their BC to stay off of the bottom, resume moving to generate lift or to just go ahead and settle to the bottom. Moving on from this level of experience the typical yo-yo diver will probably move into the rototiller level where they have given up on controlling buoyancy and are content to till along the bottom with their fins while their head is up by two or three feet. This is often the level at which divemaster has been achieved and it is not uncommon to see an accomplished rototiller *leading* a pod of yo-yos. Of course the only time the yo-yos can see anything is at the top of their swing when they can finally looking over the cloud of turbidity coming from the fins of the divemaster/rototiller.

Now I personally would suggest that you skip those levels of diivng expertise and move in a different direction. To achieve buoyancy control you will need to be properly weighted. Properly weighted you should be able to remain stationary in <10' water with minimal air in your tank (200~500 psi.) To ascertain your correct weighting you will need to go on a shore dive with an empty tank (200~500psi) and drop weights. Weight bags in a mesh belt are nice for this but you can also use hard weights in a bucket. Start ditching weight in 2# increments until you find that you can no longer stay down. Add back one 2# weight and you are now properly weighted.

Next you should practice swimming through the water in horizontal trim so that you are not adding positive or negative lift while moving. This will come easier than you might imagine if you dedicate your dive to geting the correct trim rather than just doing your normal dive agenda and *tacking* on trim practice.

And added benefit to correct weighting and trim is that you will move through the water much easier with much less drag and therefore your air consumption will improve dramatically. Also your CO2 retention will be much less.

 

[ShakaZulu]

What kind of BC are you using (how much lift)? Are you small in stature? Sometimes, the BC offers to much lift and if you add too much air, you'll shoot to the top. The air in your lungs affect bouyency at 20ft a lot. Use small squirts of air, and allow time for the increased/decreased bouyency to take place. It's not a on/off switch. Try to use the rear dump valves in your BC, so that you don't have to go vertical to dump air, this has a tendency of making you more positive. Dive more.............

 

[MyDiveLog]

First off, relax; your problem is the most common one encountered by new divers. It IS solvable, partly with simply more dives. My experience is that, somewhere between 20 and 30 dives a lot of this just seems to "click" for new divers.

I can give some general hints on how to improve bouyancy control, but would probably be more "on target" if I knew a few more things about you & yoru diving:
1) What kind of water are you diving in & what temp? (assume fw, since you're from the mid west).
2) What kind of exposure protrection are you wearing?
3) How much weight are you carrying?
4) What's your height & weight? Would you characterize yourself as "skinny", "normal", or "plus-sized" ... the ratio of one/muscle/fat changes your inherent bouyancy a bit, but not nearly as much as people think.
5) How do you descend? Are you able to vent your BC & descend easily in a head-up position, or do you need to swim down to get to depth?
6) Do you need to add a couple of quick puffs of air at depth to get neutral, or in a number of long bursts?
7) When your BC is fully deflated at depth, has your buddy confirmed that it actually IS? Often times new divers have their body positioned so that the vent is below the air bubble in their BC. They assume they're vented when they aren't.
8) What brand/model of BC do you have & where are the vents?

To respond to your questions, definately NO on going deeper to resolve the issue. If you are over-weighted (most new divers are), then the problems will get worse, not better. You'll vent air, then realize you're descending way too fast, so you blast air into the BC. There's a delay in the response to this, so most new divers over-shoot, then realize they are now rizing too fast, so they vent...usually too much, and the process repeats itself. I've heard it referred to as "elevator diving." In the worst case, they end up shooting to the surface from too great a depth, risking a DCS hit.

Make sure you know where the 2 or 3 vents are on your BC and are able to reach and use them comfortably uw. If you are head down or swimming laterally, it's usually easiest to vent air from the vent at the back/bottom of your BC. If you are "head up" then the vent on your inflator hose or opposite shoulder (if you have one) makes more sense. Make sure you tilt slightly to the side to place raise the vent a bit. New divers sometimes also only raise their inflator hose a bit when venting, leaving it in a "U" shape. Since air wants to rise, the air in the BC doesn't vent much or at all. Make sure you pull the inflator hose fully upward when using it to vent. The Seaquest BC's all you to dump air simply by pulling down on the inflator hose, which obviates this problem.

Probably most importantly, did your instructor take the time to work through bouyancy issues with you prior to your ever putting on scuba? Are you able to comfortably float in a swimsuit in the shallow end of a pool, exhale fully, and lie on the bottom? If you can't, there's a chance you're holding air in your lungs, which can add 10 - 12 lbs of bouyancy. Beachdivequeen recommended some 'games' on scuba that do much the same thing.


Good luck & hang in there...don't let normal challenges sour you on the sport. That state of neutral bouyancy, once you can acheive it, is almost magical!

 

[Xanthro]

If you can get to the bottom at 20 feet without swimming down, then you don't need more weight.

Too much weight makes it HARDER to maintain control.

People have already posted good information. I'll just add, don't allow momentum to build up. You should descend and ascend slowly. It's not a race to the bottom, nor the top. As you descend, add air to your BC before you start to gain speed, as very small burst will do. Changes to your bouyancy take time to take affect.

People keep saying practice, because practice is what allows you to gauge when to add air to your BC and when to vent, without gaining too much speed.

I like to descend where a good breath will stop the descend, and ascend where near full exhale will stop the ascend.

Also, remember that tension affects bouyancy. If you are relaxed, you'll sink, if your are tense or flex, you'll raise, assuming at the time you're neutral.

Remember, everyone has to work or bouyancy in the beginning, you're not alone. Plus, the vast majority of divers are trying to improve even after many dives. I tried Uncle Pug's ascending horizontal and face up, and let's see the results weren't what I was hoping for. LOL.

Xanthro

 

[Jason B]

hey up, good post!

 

[OE2X]

You don't need help with your buoyancy... you need help with your buoyancy control. This is an important distinction.

First there is a difference between static neutral buoyancy and dynamic buoyancy control. You can achieve perfect neutral buoyancy only to have it *disappear* the moment you start moving. Since most divers are constantly moving they never really know if they are neutrally bouyant or not because of the dynamic forces effecting them as they move through the water.

Secondly trim (body position in the water) plays a critical role in dynamic buoyancy control. At the base level understand that when you move forward through the water at the typical heads up body inclined up trim a lifting force is being generated. Your body is like an airplane wing moving through the water. To counter this upward lifting force most divers will be carrying extra weight. When they stop moving forward the lift is lost and they sink. They have the choice of adding air to their BC to stay off of the bottom, resume moving to generate lift or to just go ahead and settle to the bottom. Moving on from this level of experience the typical yo-yo diver will probably move into the rototiller level where they have given up on controlling buoyancy and are content to till along the bottom with their fins while their head is up by two or three feet. This is often the level at which divemaster has been achieved and it is not uncommon to see an accomplished rototiller *leading* a pod of yo-yos. Of course the only time the yo-yos can see anything is at the top of their swing when they can finally looking over the cloud of turbidity coming from the fins of the divemaster/rototiller.

Now I personally would suggest that you skip those levels of diivng expertise and move in a different direction. To achieve buoyancy control you will need to be properly weighted. Properly weighted you should be able to remain stationary in <10' water with minimal air in your tank (200~500 psi.) To ascertain your correct weighting you will need to go on a shore dive with an empty tank (200~500psi) and drop weights. Weight bags in a mesh belt are nice for this but you can also use hard weights in a bucket. Start ditching weight in 2# increments until you find that you can no longer stay down. Add back one 2# weight and you are now properly weighted.

Next you should practice swimming through the water in horizontal trim so that you are not adding positive or negative lift while moving. This will come easier than you might imagine if you dedicate your dive to geting the correct trim rather than just doing your normal dive agenda and *tacking* on trim practice.

And added benefit to correct weighting and trim is that you will move through the water much easier with much less drag and therefore your air consumption will improve dramatically. Also your CO2 retention will be much less.

I went through the Uncle Pug School of bouyancy control and I must say that his recommendations were spot on for me. We worked on the basics: shallow beach dive, subtracting weight and working on trim. I dropped 10#'s and have stayed within a pound of his advice. Did the head thing as well. It works! I love being able to hover 6" off the bottom and not stir it up. One cool excercise that UP does is to bring out a magnifying glass - hover without touching the bottom and look at the critters. If you can do that w/o mucking things up then you have it nailed.