Let's discuss peoples over-reliance on BC's and over-weighting.

[TMHeimer]

I've done it when divemasters insisted I didn't need THAT much lead. Not really ideal in a coral environment without a lot of heavy rocks loose on the bottom. You have to start looking early.

Yes. Here there is no coral in shallow depths (yes, I hear Black Coral is deeper). It doesn't matter much how good you are buoyancy-wise here-other than how enjoyable will be your dive. Rocks and seaweed.

 

[northernone]

TWO reasons I've observed why overweighting is common:

1. Overweighting is the TV of parenting (or is that the ipad?) The instructors I know who overweight like to have the students easy to glue to the bottom if needed, significantly negative.. in these formative dives as students it's learned that negative is normal and the bcd is the fix.

2. Later, it's easier to add a puff of air in a bcd if overweighted then to pull an extra lead block out of your %*\ even needed if you've erred on the side of under weighted. So I know guys who toss on a few extra lbs(kgs) to avoid struggling with being light the whole dive.

If I'm not diving with buoyancy redundancy I have a few weights I can ditch separate from my main weights to insure I can comfortably hold deco in mid water without building up CO with shallow breathing or struggling the whole time swimming up.

Outside of the OP topic scope is the wildcard of deep diving in thick wetsuits and multiple cylinders. The buoyancy swing from deep full tanks to shallow empty tanks (emergency requiring more gas consumption) is significant in some rig configurations and unsafe to try to use lung volume to compensate for this.

Dive safe,
Cameron

 

[Storker]

And one trick to diving without a BC is to wear too little lead, swim down hard and suit compression will take over after a certain depth. When you are ready to ascend (if there is no rope to climb) you grab a 6 or 8lb rock and kick up. You carry the rock until you reach the surface and then drop it.

The "carry a rock" trick works pretty well if you're a little underweighted with a BCD, too. I've used it on occasion, when I've underestimated the extra amount of weight I needed to compensate for the additional undergarment I added when the water got cold. When I do the "carry a rock" trick, I try to find a somewhat long, narrow and flat - or at least flat - rock that I can stick under my harness and keep my hands free(ish).

 

[AfterDark]

I believe that they shall put the Buoyancy course in between the OW and AOW, and make that course a must before getting your AOW, and put the time in there to do it right.

Great idea, make another course for something that is scuba 101, charge more and make it a must have cert. You should apply to PADI for a job.

 

[Diving Dubai]

This is a subject close to my heart. I deplore over weighted divers. One of my hobbies has been to reduce teh weighting of even experienced divers. I have never had to buy the drink that was the bet...

Of course initial instruction is the starting point, but then people use lead as a comfort blanket. You'll often hear them say tell you that their instructor told them they needed X weight, and so that's what they've always used. On trips away I'll see young fit petite girls with 3 - 4 times the lead that I wear, and I'm a slightly pudgy middle aged tall guy.

Occasionally I've mislead clients, by pretending to give them the weight they demand (or slip some off between dives, only then after the dive or dives when I tell them do they realise.

Sometime on week long trips people can be persuaded to lose weight (or they remove it by themselves), The simple fact is that if you're diving infrequently then you have little chance to work on your weighting.

People also get so accustomed to a certain over weight that their "technique" is developed around diving that weight, and it takes some effort to "learn" to dive with less

Some people have no interest in perfecting their weighting and it does require some practice and effort (especially for those divign over weight for a long time) Others do have an interest and are amazed at the difference it can make.

I have to carry extra weight on some dives which is fine, but removing it and going back to perfect weighting is a lovely feeling

 

[Killerflyingbugs]

and I'm a slightly pudgy middle aged tall guy.

Me too I'm 6 ft 10 inches tall and a little soft in the middle.

 

[dumpsterDiver]

Me too I'm 6 ft 10 inches tall and a little soft in the middle.

No wonder you don't need a BC. You can just stand up if there's a problem

 

[Killerflyingbugs]

 

[spoolin01]

I suspect divers learn early to carry too much weight because as has been alluded to, the usual protocol when learning is to float at the the surface in a group, then drop as a group, and you need extra lead to make that drop happen, NOW. I suspect a lot of folks also like that kind of responsiveness. I have a friend who just cannot be convinced to drop any other way, and she is regularly over-weighted by a small amount, by my standard.

On the other hand, who cares (within limits)? There can be good reason to want to carry extra lead when shallow, wanting to be able to immobilize on the bottom for photography or just watching, especially with surge.

Less lead for less lead's sake can just as well lead to bouyancy control problems at the end of the dive. Even just enough might not always end up being adequate or preferable.

If you are happy overall with your bouyancy, who cares if someone else would choose less?

 

[dumpsterDiver]

I suspect divers learn early to carry too much weight because as has been alluded to, the usual protocol when learning is to float at the the surface in a group, then drop as a group, and you need extra lead to make that drop happen, NOW. I suspect a lot of folks also like that kind of responsiveness. I have a friend who just cannot be convinced to drop any other way, and she is regularly over-weighted by a small amount, by my standard.

On the other hand, who cares (within limits)? There can be good reason to want to carry extra lead when shallow, wanting to be able to immobilize on the bottom for photography or just watching, especially with surge.

Less lead for less lead's sake can just as well lead to bouyancy control problems at the end of the dive. Even just enough might not always end up being adequate or preferable.

If you are happy overall with your bouyancy, who cares if someone else would choose less?

To a large degree, I agree with you. As long as the diver has enough ditchable ballast to survive a total BC failure AND they can perfectly manage their ascents and descents...carrying extra lead is not a problem.

Way too many people view scuba as a competition - seeing how little air they burn and how little lead they need. They don't have any good metrics to compare divers, so they gravitate to using these quantifiable parameters as indicators of competence. Both of these "obsessions" have very little value in my book.

I often carry extra ballast so that I can work effectively and be stable in a current. In warm water, I wear a 2 mm full suit and dive with various steel tanks, use a recreational BC and require ZERO lead. I can often get two dives from my 149 cu-ft tank. On the first dive when I head down with 3700 psi, I am really pretty heavy. If I take it on a second dive and run the pressure down to 400 psi or something on the safety stop, I am quite a lot lighter. So when I use this tank, with this exposure protection, I can not really fine tune my ballast. For the first dive, i am heavier than I need (or really want) to be.

The problem with excess lead is that many people "can't handle it" at it complicates their buoyancy control and can cause out of control ascents - especially with a thick wetsuit - since they got the double whammy of expanding air in the BC and expanding wetsuit.

The extra (unnecessary) lead causes them to have excess air in the BC at depth and this does not enhance their hydrodynamic efficiency due to drag AND difficulties with trim. So it is not beneficial to wear too much lead, but I think there is a somewhat blurry line between being "over" weighted versus just carrying a little extra lead.

As a DM, I have seen idiots make extremely poor decisions and have even gone so far as to DEMAND that they reduce ballast or I would refuse diving with them. When you see someone who THINKS they need much, much more lead than they need, then I KNOW they are unsafe and incompetent and have stepped in to avert an accident. Typically this is someone who has only dove in cold water and thick wetsuit and then comes to Florida with a shorty and tries to use the same amount of lead.