How much weight do YOU use?

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ZAquaman:
.... And never think that it's a bad thing to be using more weight than your buddy. If you're neutral at the surface with an empty tank and an empty BC, you're just right!

Good summaries. It cracks me up how many new divers (and some with more experience) think the weight they use is some sort of measure of skill. While it can be if a diver tries to descend with air in the BC, etc., there are so many factors that determine necessary weight. You see some people announce they use X lbs of weight and someone else jumps in to say "wow that is too much weight" without knowing gear/body type. This identifies the person with the comment has no idea what they are talking about. They don't even know if they are talking about a trilam suit with summer thermals and steel tanks or a thick neoprene suit with tons of thermals and alum tanks. Not in all cases but you can find these posts. You need what you need. Take the necessary steps to ensure you are not overweighting of course.

--Matt
 
Good observations but I thought the thread asked for general gear type by general catagory and most people gave it so the remaining factors not asked for was body type. Another pointed out lung capacity and that was a good one as well that differs between people. Still, it is hard to figure how people in the same setup have weights that run from a couple of lbs to over 30 lbs? Interesting certainly. Too bad we cannot go back and add body type, height, weight, gender etc., and body fat % if known. I doubt many people know their lung capacity--lol. Good thread anyways. N
 
Tri-lam dry suit
Polar fleece and long johns
Zeigle Ranger BC
Al 80
6'2"
15% body fat

35 lbs salt water-30 lbs fresh


When I free dive with a wetsuit, I load up to be neutral at 40-50 feet. That means I'm packing 15 Lbs in salt water and 10 lbs in fresh. Buoyance changes a huge amount when freediving due to lung volume chage and suit compression. I float like a cork at the surface and sink like a rock below 60 feet.

I've noticed that the salinity of the water makes a difference in weight requirements as well. When I'm on vacation diving tropics, or if I'm using different gear and don't know what my weight requirements will be exactly, this is what I do to find out what weight is right:

Most tanks change about 5-7 lbs full vs empty, steel, aluminum, high pressure, whatever. So I just jump in, add weight until I'm neutral at the surface with the BC empty. Then add 3-5 lbs of lead. The extra lbs keeps me from floating of my saftey stop @ 15 feet.
 
Why does "how much weight" I wear important to some many people? Someone can wear 2# of weights with steel tanks(-6), steel backplate(-2), canister light (-2), big knife(-1) would equal someone with 10# of weight with with aluminum tanks(+2), aluminum backplate(-1), tourch light (0), bc knife(0).

So is the guy with 10# of weight any different than the guy with 2#??? The weight can easily change it shape into other items.

(My numbers might be off)
 
"Why does "how much weight" I wear important to some many people?"

I think it was because the original poster was interested in what other people use so as to help him/her find a good starting point and perhaps an eventual goal. I see there is no consensus but like I said, good thread. Some people like a lot and some people like a little, some people feel like a nut and some people don't. (advertizing jingo from way back--lol) N
 
ZAquaman:
How you breath and lung capacity make a big difference. Average lung capacity is around 5 liters for most people. Each liter of air in the lungs has 1kg of lift (2.2 lbs). Some of us have larger chest and lungs (I know some folks with over 10 liters of lung capacity!), some have smaller than average chest and lungs.

Most people don't take this into account when talking about weights. They assume lotta weight = lotta fat. That's true enough, fat floats. But don't make it a numbers game. You can't predict the health of a diver or his skill by the amount of weight they use.

Get your weight right for you and your equipment. Use the same setup as much as possible and leave as much weight as you can on the boat or on shore. And never think that it's a bad thing to be using more weight than your buddy. If you're neutral at the surface with an empty tank and an empty BC, you're just right!

I hate to correct you on this but you are wrong.. The amount of gas volume displaced INSIDE a rigid container (your body) has no effect (well extremely little) on buoyancy.. Your buoyancy shift from taking a breath has very little to do do with actual lung volume.. Your buoyancy is altered by how much your BODY displaces.. There is not a 1:1 correlation.. It will vary by individual but the amount of delta diplacement is small.. You see only a small buoyancy shift.. in reality the volume change for an avg adult is somehwere in the range of 3 liters (you always have something left in your lungs),your WATER displacement change should be less than this..

I challeng you to get yourself perfectly neurtral at the bottom of a pool (minimal breathing volume) , then grab a 3 kg weight a take a DEEP breath.. You will not come off the bottom...
 
padiscubapro:
I hate to correct you on this but you are wrong.. The amount of gas volume displaced INSIDE a rigid container (your body) has no effect (well extremely little) on buoyancy..
If you're going to correct someone, at least be right.

The human body is not rigid.

Every liter of air you inhale is one more liter of volume your body takes up. The vital capacity of the lungs (the difference between maximum inhalation and maximum exhalation) for most people is around 4-5 liters, give or take. That means that you can change your body's own buoyancy by 4-5 kg just by breathing.

Normal breathing changes your lung volume from .5 to 1 liter between an inhalation and exhalation. There is generally about 1 *more* liter you can exhale at the bottom of the exhalation, and 3 *more* liters you can inhale at the top of an inhalation. All of this directly affects your buoyancy.

I can make myself 3 kg (almost 7 pounds) more positive or 1 kg more negative
(over 2 pounds) just by breathing in the correct range.

I find it very surprising that an instructor of your level does not understand basic diving physics.
 
padiscubapro:
The amount of gas volume displaced INSIDE a rigid container (your body) has no effect (well extremely little) on buoyancy.. in reality the volume change for an avg adult is somehwere in the range of 3 liters (you always have something left in your lungs),your WATER displacement change should be less than this..
Just to prove to you how silly this sounds, keeping the body's volume constant while you put 3 liters of air into it would require that the air in the body have a constant volume and you're increasing the pressure.. just like filling a scuba tank.

Inhaling is not a matter of pumping air into a rigid space.. it's a matter of making the space larger and keeping the pressure constant. The pressure in your lungs exactly equals the pressure in the mouth. There is nothing pumping air into or out of the lungs.. the diaphragm and chest muscles *expand* the lungs, so air rushes into them.

Wrap some duct tape tightly around your chest while taking normal breaths.. then take a very deep one. Tell me your chest doesn't expand.
 

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