How do you feel about upside down trim pockets on waist for BP/W ballast solution?

[BRT]

If I threw you into the Sea of Cortez in your swimsuit and handed you 12 lbs of ballast how long could you tread water?

Tobin

Well I've never been in the Sea of Cortez, but with a snorkel, so I didn't have to hold my 15lb of ugly fat out of the water to breath, I think I could tread water a long time holding 12 lb. I have to swim down like crazy to freedive in saltwater without any wetsuit. Think it might be the air in my head? Or is it some Zen thing that lets me overcome simple physics?

I just went over to a free diving forum and it appears there is a wide range of opinions there. Difference is everybody agrees that if they are going deep they can use less weight (lung compression). Of course they don't do safety stops. Kind of crazy to hear about people wearing 12-17lb for shallow freediving. Then there are the people who can do it with no weight at all and think everybody should.

Like I said before, I'm jealous, but I still need 14-16lb in my Lavacore. And I still believe lead is warmth in a drysuit.

---------- Post added April 27th, 2015 at 10:57 PM ----------

FWIW, I did a session in the pool the other night with a 6lb plate in a 3/2 full suit and an AL80. I was over weighted. Hared pressed to see where I should need more than a copuple of pounds at most in salt with the same config.

Let me see....if that was me...210lb for me plus 6 lb for the backplate, 4 lb for the suit, 42 lb for the AL80 with air and valve, 2 lb for the reg, 4 lb for the fins would give me a total weight of 268. Add 2.5% of the weight of the fresh water I am displacing to replace it with an equivelent volume of salt water would be 6.7lb. You were heavy with the AL80 but you probably didn't breath it empty in the pool either. I think by the end of a dive in saltwater you may need more than a couple extra pounds.

 

[cool_hardware52]

I think I could tread water a long time holding 12 lb. I have to swim down like crazy to freedive in saltwater without any wetsuit.

Try it and let me know.

Tobin

 

[decompression]

BRT, could you try something for me? This is what I do with my students to get them in the ballpark for weight.....previous to this we have spent time in the pool, just suits, using their lungs, controlling their position in the water. Also, adding lead (usually2-4 lbs) or buoyancy (neoprene vest) to get them neutral.

Wear your full suit with hood gloves boots....into the pool or calm body of water (ensure fresh or salt is factored in later).
Exhaust as much air as possible (dry suit), have your BCD on deck or floating with reg in your mouth and grab 1lb weights, until you sink when you exhale.
This will confirm your suits/undergarment positive buoyancy. I estimate around 20-25 lbs.
From there you can easily establish the neg or pos of your equipment.
Place jacket BCD in a mesh bag and add lead until it sinks.
For bpw and regs and all neg items just weigh them or check manufacturing specs.
Check the tanks that you use specs for pos or neg.
Now you've got all your positive buoyancy and all your neg.

Minus the neg from the pos and that gives you the correct amount of lead to add.

The weight of the gas is compensated by the lift provided by the wing. Which can be exhausted as the air is used.
The squeeze of the suit can be reduced by adding air when diving, just enough for comfort. This will replicate closely what it was like in the shallows and not adversely affect the calculations.

This is a balanced rig calculation. Note that body weight isn't a large part of the equation as tissues are a large part water anyway. The extremes of body type are to be considered, certainly due to exposure suit size and its part in buoyancy.

Then this is confirmed by a weight check.

You've probably heard this many times but I do think you are considerably over weighted, there is a chance you are not and this would solidify in your mind that you have the right amount for you.

The downfalls of overweighting are many (dynamic instability, unnecessary air use, increased drag, difficulties exhausting leading to rapid ascents......).

This is why weight is such an important issue and one that gets far less attention than it should.


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[BRT]

BRT, could you try something for me? This is what I do with my students to get them in the ballpark for weight.....previous to this we have spent time in the pool, just suits, using their lungs, controlling their position in the water. Also, adding lead (usually2-4 lbs) or buoyancy (neoprene vest) to get them neutral.

Wear your full suit with hood gloves boots....into the pool or calm body of water (ensure fresh or salt is factored in later).
Exhaust as much air as possible (dry suit), have your BCD on deck or floating with reg in your mouth and grab 1lb weights, until you sink when you exhale.
This will confirm your suits/undergarment positive buoyancy. I estimate around 20-25 lbs.
From there you can easily establish the neg or pos of your equipment.
Place jacket BCD in a mesh bag and add lead until it sinks.
For bpw and regs and all neg items just weigh them or check manufacturing specs.
Check the tanks that you use specs for pos or neg.
Now you've got all your positive buoyancy and all your neg.

Minus the neg from the pos and that gives you the correct amount of lead to add.

The weight of the gas is compensated by the lift provided by the wing. Which can be exhausted as the air is used.
The squeeze of the suit can be reduced by adding air when diving, just enough for comfort. This will replicate closely what it was like in the shallows and not adversely affect the calculations.

This is a balanced rig calculation. Note that body weight isn't a large part of the equation as tissues are a large part water anyway. The extremes of body type are to be considered, certainly due to exposure suit size and its part in buoyancy.

Then this is confirmed by a weight check.

You've probably heard this many times but I do think you are considerably over weighted, there is a chance you are not and this would solidify in your mind that you have the right amount for you.

The downfalls of overweighting are many (dynamic instability, unnecessary air use, increased drag, difficulties exhausting leading to rapid ascents......).

This is why weight is such an important issue and one that gets far less attention than it should.


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Decompression, I appreciate your help and interest. I need to go to a local lake to try this exercise sometime this summer. Please answer some questions. If with my current weighting, a very low tank, say 300psi and no air in my BCD I can float neutrally, why would I want to know how little lead I can wear with all possible air exhausted from my drysuit? I'm not going to dive it that way. I'd be cold, and I like diving warm. Standing in water up to my neck I can get air out of the suit much faster and easier and more completely than I can at any other depth or position. Why would I want to weight myself so I have to exhaust that much air to stay down at the end of a dive with low air in my tank? If I am approaching a 15 foot safety stop and feel light how much time do I have to get my left shoulder at the highest position, legs straight down and concentrate on trying to get my suit as empty as I could standing in water up to my neck? At that 15 foot point what are my options? BCD is empty so I can't dump that. If I turn and swim down I can't exhaust any air. What I do in that situation is raise my left shoulder slightly and the problem is cured.

Thanks in advance for your answers.

 

[decompression]

Decompression, I appreciate your help and interest. I need to go to a local lake to try this exercise sometime this summer. Please answer some questions. If with my current weighting, a very low tank, say 300psi and no air in my BCD I can float neutrally, why would I want to know how little lead I can wear with all possible air exhausted from my drysuit? I'm not going to dive it that way. I'd be cold, and I like diving warm. Standing in water up to my neck I can get air out of the suit much faster and easier and more completely than I can at any other depth or position. Why would I want to weight myself so I have to exhaust that much air to stay down at the end of a dive with low air in my tank? If I am approaching a 15 foot safety stop and feel light how much time do I have to get my left shoulder at the highest position, legs straight down and concentrate on trying to get my suit as empty as I could standing in water up to my neck? At that 15 foot point what are my options? BCD is empty so I can't dump that. If I turn and swim down I can't exhaust any air. What I do in that situation is raise my left shoulder slightly and the problem is cured.

Thanks in advance for your answers.

No worries BRT,

When you say float neutrally I assume you mean be neutral under water.
So, with your current weight (54#) and 300 psi in your tank, no air in BCD and you are neutral......that's the right weight.

Although, how much air is in your drysuit? This is the fine line between warmth and the inability to properly control the air in your suit.

Firstly, you have to agree to the downsides of excessive air, if you don't then there is no reason to strive for this goal. Which is the minimum amount of air while still being warm and functional.

So, just to make sure we're on the same page, getting rid of air at the surface for the test, your suit is "roughly" the same buoyancy as at depth (with added air)....all due to the pressure.
This simulates actual dive conditions, now, you favor lots of air so this wouldn't feel right to you. The more air in your suit doesn't necessarily equate to warmth, that's the undergarment. The amount of air is to reduce squeeze and let the undergarment perform as designed. Granted, a squeezed undergarment is less effective. Why I think you maybe overweighted is there aren't many undergarments that are 50 lbs buoyant. But if your DS is thick neoprene and a heavy undergarment then it's possible that +50 is required.

Although, I had a suit leak on a 90 min dive (no air in suit really) and my weezle undergarment was soaked, I was only slightly chilled. The air had little to do with its insulating properties.

If you are weighted properly, then exhausting air from your DS is almost a non issue. They can vent themselves or as you say just a quick shoulder movement.
If you have a large amount of air it will take longer to exhaust and less time to do it in the shallower you are, risking a positive ascent. The idea is to be neutral at all times.

Have I explained this ok? If not let me know.


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[BRT]

No worries BRT,

When you say float neutrally I assume you mean be neutral under water.
So, with your current weight (54#) and 300 psi in your tank, no air in BCD and you are neutral......that's the right weight.

Although, how much air is in your drysuit? This is the fine line between warmth and the inability to properly control the air in your suit.

Firstly, you have to agree to the downsides of excessive air, if you don't then there is no reason to strive for this goal. Which is the minimum amount of air while still being warm and functional.

So, just to make sure we're on the same page, getting rid of air at the surface for the test, your suit is "roughly" the same buoyancy as at depth (with added air)....all due to the pressure.
This simulates actual dive conditions, now, you favor lots of air so this wouldn't feel right to you. The more air in your suit doesn't necessarily equate to warmth, that's the undergarment. The amount of air is to reduce squeeze and let the undergarment perform as designed. Granted, a squeezed undergarment is less effective. Why I think you maybe overweighted is there aren't many undergarments that are 50 lbs buoyant. But if your DS is thick neoprene and a heavy undergarment then it's possible that +50 is required.

Although, I had a suit leak on a 90 min dive (no air in suit really) and my weezle undergarment was soaked, I was only slightly chilled. The air had little to do with its insulating properties.

If you are weighted properly, then exhausting air from your DS is almost a non issue. They can vent themselves or as you say just a quick shoulder movement.
If you have a large amount of air it will take longer to exhaust and less time to do it in the shallower you are, risking a positive ascent. The idea is to be neutral at all times.

Have I explained this ok? If not let me know.


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We can agree on excess air being bad. How much is excess is where we may disagree. For info I am wearing a DUI CF200 neoprene suit, a Whites undergarment and long underwear under that, wool socks, 6.5mil neoprene booties, 5 mil wet gloves and a Waterproof 5/10 hood. When I walk into the ocean with my vent valve open my drysuit vents air until my legs and lower body are covered by a drysuit that is just tight folds. . No question I am heavy. I keep some air in my BCD as I put my fins on so I lay down in the water, pull a dump and drop. As soon as I am under I squirt air into my suit and BCD and as I go down I put air in my suit to maintain about the same floatation and warmth. As I use up my tank I feel a little floaty and dump BCD air. Coming up I raise a shoulder or if needed open my dump valve a click or 2. Now the sticker. As I am going along at depth through my normal motion my suit will dump air whenever my shoulder gets high. I will find myself getting cold, so I close the dump a few clicks and put in some air. I know you guys are telling me it doesn't work but somehow I get warmer almost immediatly. Placebo maybe? No I don't think so. 1 lb or even 1/2 lb per square inch will compress my insulation layer. 2 psi will compress it a lot. A thinner insulation layer will insulate less. When I come up in the water column and start to get a bubble moving around a lot I don't like that and take care of it.

If I swam any amount I would be too warm. I usually have a 3442 steel 100 and commonly do an hour with max depths below 70 feet, lots of time at 15 to 30 feet and come up with 12-1500 lb. I'm just not doing anything so I don't use air and don't create heat.

In the 90's I dove a shell suit with about 35lb of lead IIRC. Froze every dive. That I remember well. Now except for my hands I am toasty for as long as I stay down. Dry gloves may be in my future.

I disagree strongly with you about exhausting air from a drysuit being a non issue. When my suit is tight it is very slow to get more air out of it and I have to get my legs down and my shoulder high and wait for air to migrate. Raising my left arm above me will create a place for air to go and then dropping the arm will help it vent but takes time and positioning. When I have some air in the suit I can exhaust some very rapidly. Is yours different from that?

I think the Weezles claim to fame is that it maintains loft when wet. Loft is the air space that actually insulates. Do you use the Extreme+?

 

[decompression]

You know, BRT, I think you are pretty much where you should be. I've had 4 shell suits, 1 compressed neoprene, a hybrid and and now a fusion. The shells were easy to vent, the neo was challenging (as you're finding) and my fusion is super easy.

Large amounts of Air will vent much faster as you've noticed, the goal with the exercise is to balance the weight and air so you don't have to vent as much air that's compensating for the lead. Especially as you have a neoprene suit which has inherent warmth but little dynamic change so the weighting for the suit should almost be a constant.

Your description of your dive procedure seems spot on, with the exception of the loss of air and its replacement. Certainly you could keep the valve closed afew more ticks and be conscious of loosing the air. Not really a big deal though as you've found.

I have to say, if when your DS vents you get cold and this is relieved by adding air, it's obviously the compression of the undergarment........

So, after all this.........I think you're good. [emoji3]

All the equipment you've mentioned have a fair amount of buoyancy, you've found the "warm spot" with the amount of air you use.

I'd love to try the exercise with you as I'm pretty sure we could drop 5-10 lbs......but honestly you seem happy where you are, so why change? It would be fun to find out, if you do ever get around to it, let us know if there was a change of not.

Cheers.

Jay



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[BRT]

My wife had a shell suit and she was fighting the bubble. We got her a Fusion and that complaint went away.

I really don't have problems venting the CF200 unless I'm trying to get it to squeeze down tighter than I would like to dive it for warmth. We spent 16 years away from cold water diving. Coming back to a drysuit I had a few issues early on before adding more weight but no full rides to the surface except when I dropped a weight pouch. My weight is a bunch more distributed now. Coming up I'd carefully vent my BCD and then struggle to get enough air out of my suit to avoid the ride. It is a lot easier when I have enough air in the suit to just tip a shoulder up to make an adjustment. And I'm a bunch warmer. I'd sure rather walk to the water carrying less lead!