More experience = Less weight

[ScoobaChef]

I was talking about my weighting one of the instructors at my lds the other day and he told me that as I gain more experience, I won't need to use as much weight as i currently use.

I know I'm still pretty much a noob, but I'm having trouble wrapping my head around this, because:

1. I'm about 135lb, 7mm semidry, 6# ss backplate and 15# ditchable weight, ally 80 tank.

2. I can easily swim up my rig with an empty wing.

3. When I did a test with 18# total weight, i could not sink at all even with an empty bc and fully exhaling.

What am I missing here?

 

[nolatom]

I would guess you're trapping some air in your suit, which will squeeze and osmose out during the dive. I don't know why that seems to happen less as you have more time/experience, but it does.

So does the relaxation that comes with more hours.

I don't know the science, but with the same gear I used to carry 14 pounds for, I'm now down to 8. Maybe the wetsuit has crushed down a little on buoyancy, but not enough for 6 pounds worth.

 

[SOFDiver]

ScoobaChef

Your instructor was trying to tell you that most divers as they gain experience use less weight because they better control their breathing, which in turn helps bouyancy control. The more you dive the better your diving skils will become, and the more efficent you will be.

 

[Angry Turtle]

Your comfort in the water has a lot to do with it. As new divers a lot of us would hyperventilate, even while unaware of it. I went from using 10-12 lbs to just 6 with an Al80 in a 3 mil.

Some instructors also overweight students to make them more manageable in the bottom (to the students detriment) and when people later are more comfortable they shed that weight as well.

 

[motorref]

Your comfort in the water has a lot to do with it. As new divers a lot of us would hyperventilate, even while unaware of it. I went from using 10-12 lbs to just 6 with an Al80 in a 3 mil.

Some instructors also overweight students to make them more manageable in the bottom (to the students detriment) and when people later are more comfortable they shed that weight as well.

I think AT has hit it on the head; when I first started (in 2010?)I was using 26# (10% of my body weight); on my last vacation prior to surgery last year I was down to 16#, using the same equipment/shop.
Comfort is a big issue, as is learning to relax and breathe properly - it'll come to you with more dives!

KevinL

 

[fjpatrum]

ScoobaChef, I'm not much further along than you, dive #s-wise. I found a difference of only 1 pound this past weekend did matter for me. I'd consider dropping by smaller increments and you'll find that you probably will lose some weight off the belt. When diving wet for cold I wear about 14 pounds and my plate. That's wearing ~14mm on my core with various levels down to 3mm on my lower legs. I'm 6'1 170. Diving dry this past weekend I found I'm essentially right at the same weight. My plate plus 14.5 pounds or so is perfect but 16 pounds I am constantly sinking and 13 pounds I'm too light.

 

[fnfalman]

I was talking about my weighting one of the instructors at my lds the other day and he told me that as I gain more experience, I won't need to use as much weight as i currently use.

That's a simplistic explanation and to me it's a cop out so that they don't have to teach you about proper weighting and proper descension/ascension techniques.

I know I'm still pretty much a noob, but I'm having trouble wrapping my head around this, because:

1. I'm about 135lb, 7mm semidry, 6# ss backplate and 15# ditchable weight, ally 80 tank.

2. I can easily swim up my rig with an empty wing.

3. When I did a test with 18# total weight, i could not sink at all even with an empty bc and fully exhaling.

What am I missing here?

Same BC? Same tank? Same everything?

Also, if you own your wetsuit, the dang thing is going to lose some positive buoyancy with use.

 

[emoreira]

I would say

more experience = right amount of weight

This of course, related to the gear you are using, more precisely the exposure protection.

 

[ScoobaChef]

Thanks everyone, some good info so far.

fnfalman - exact same equipment, same fill pressure, same conditions. (I prefer the FiveSeven btw

nolatom - good point about the wetsuit, I hadn't thought about it losing buoyancy with use and age.

I should clarify a few points.

1. I'm reasonably comfortable in the water with my current weighting, can stay within 1 metre of target depth while slowly swimming and can (most of the time) maintain a static horizontal hover within 2 metres. I only have a shot or two of air in my bc at depth to compensate for suit compression and only use breathing to control my buoyancy. No bottom smashing or corking.

2. When I lightened my weight by 3lbs (1block), I was completely unable to submerge even after emptying my wing and exhaling as completely as possible. I did a duck dive and was able to swim down, a bit, but floated right back up.

So I guess a better question would be: How can I be overweighted if I can't even forcibly swim down, and if I am overweighted, how does experience address this situation?

 

[SangP]

Thanks everyone, some good info so far.

fnfalman - exact same equipment, same fill pressure, same conditions. (I prefer the FiveSeven btw

nolatom - good point about the wetsuit, I hadn't thought about it losing buoyancy with use and age.

I should clarify a few points.

1. I'm reasonably comfortable in the water with my current weighting, can stay within 1 metre of target depth while slowly swimming and can (most of the time) maintain a static horizontal hover within 2 metres. I only have a shot or two of air in my bc at depth to compensate for suit compression and only use breathing to control my buoyancy. No bottom smashing or corking.

2. When I lightened my weight by 3lbs (1block), I was completely unable to submerge even after emptying my wing and exhaling as completely as possible. I did a duck dive and was able to swim down, a bit, but floated right back up.

So I guess a better question would be: How can I be overweighted if I can't even forcibly swim down, and if I am overweighted, how does experience address this situation?

There are many factors but a lot of times, newbie divers don't know what they are doing wrong. Like finning up while trying to release gas n go down. Hyperventilating and inability to stay calm.

However, no matter what you can't beat the laws of physics. If you are underweighted there is no way you can sink.

Put a couple more pounds and try this. It's called the dead man's drop. Dump all the air, close your eyes, stop moving n go limp. If you are completely limp, have closed your eyes and still can't go under, you are underweight.

A lot of times the more experience divers say they need less n less weight, well it's true they are more relax but also a lot of their gear is pretty well used but often they have some special techniques lol. Wetsuit is less buoyant due to compression after some time, bcd is well used and like an old backpack, the padding is pretty much gone. I remembered seeing this and wondering why they did it. A lot of dm I knew used to soak their bcd in water before tanking up, I now realize that it's makes the cam bands more secure but also removes a lot of residual air in the bcd.

Cheers