Question about exceeding the 'loadable weight' of a BCD

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Get a DUI weight harness and divide the weight. It will also allow you to change your trim up and down on your body. Different people dive with different weights. Less is nice, but floating up at the end of a dive is terrible. Don't let anybody tell you to take off weight unless they are willing to carry the additional for you through the end of the dive in case you need it. I had a know it all divemaster tell me they would have spares, but they lied. I ended up with a big rock off of the bottom.
Thank you. I wanted to go in with 30 lbs which was the correct amount for a 2 piece 7mm. The divemaster probably didn't realize it and told me to just use 24 lbs, which was correct for a 1 piece 7mm. Since I'm very new, you could imagine how puzzled I was when I couldn't go down at all.

He did carry extra 4 lbs for me but wasn't quite enough for a noob like me and led me to float up in the end.
 
Thank you. I wanted to go in with 30 lbs which was the correct amount for a 2 piece 7mm. The divemaster probably didn't realize it and told me to just use 24 lbs, which was correct for a 1 piece 7mm. Since I'm very new, you could imagine how puzzled I was when I couldn't go down at all.

He did carry extra 4 lbs for me but wasn't quite enough for a noob like me and led me to float up in the end.
I hate being too light. It gets worse if you end up with enough nitrogen that you really need to stay down on the safety stop, and are low on air so you are lighter than normal. You end up swimming head down to maintain depth when you really need to relax and conserve your air and breathe off some N.
 
I have seen many new divers think they have a fully deflated BC (jacket style) not realizing that the way they are trying to dump air is leaving a huge air bubble in the bladder. Poor sizing and the shoulder dump is on the front of the shoulder not the back. A dip in the inflator hose. Or simply not lifting the inflator hose above the air bubble on there back. Now there is an air bubble they don't realize they have and try to fix it with more weight. All too common for a divemaster to throw weight at the problem for it to go away and not actually look for why the need the weight.

One of the best things to do is when getting back to shore or heading up the boat ladder at the end of the dive is to dump the air and see how negative you are. Or get neutral a foot below the surface. Get out of the water and check the bladder and see how much air is really in it. You might be surprised at how much air there is.

Another thing about diving wet. You can have a fair bit of air trapped in the suit. Makes you floaty when you first jump in. Takes a little bit for that water to leak in and make the wetsuit wet on the inside. That water leaking in is matched by air leaking out. Depending on the fit of the suit it can be a good amount of air trapped inside.
 
Holy cow that's a lot of neoprene and lead. I hated the Michelin Man suit and bricks of lead when I learned to dive in California. Now I dive a drysuit in a variety of water temps and will never dive with that much neoprene and lead again. If you stick with diving I predict you too will switch to a drysuit. And steel tank.
 
Thanks! It makes more sense now. Luckily I bought a one piece and also no need to worry about overloading my BCD. I will try out the skills you mentioned. Thanks again!

Skimming the thread I'm not sure if anyone already expounded on this: keep in mind that if you do go deep enough to lose wetsuit's buoyancy to compression, you'll have only the BCD's aircell and your fins to get you back up. I don't have a problem with wearing 20-something pounds of stuff and a 25lb wing in local lakes, but there's a hard bottom at maybe 30' on those dives and in the pool I can swim up and around in speedos and a diving brick in each hand.

Edit/PS: meaning, I wouldn't got on a 30 m dive in a #32 wing with 30lbs of lead even if the lead was all ditchable. I would go on a 10 m dive though.
 
Actually one more question. When you put in the extra weight, did you put them in the zipper pocket or the releasable pocket?
I suppose if the former, then there's no risk of the clip failing but of course the extra weight cannot quick release. But quick release 20 lbs might already be enough?
I would discourage you from loading any weight you can't ditch (minus the trim pockets) for safety reasons. The weight pockets you have should hold the weight you need to load just fine. Looks like you're getting some good advice on buoyancy/weighting from others. Just remember, you should dive with the least amount of weight you can get by with. However, everyone's body composition and gear set up is different, so use that as your guide. As a new diver, you will figure it out with experience.

I'd also recommend making detailed notes in your log book about what you wore, how much weight you used, etc so you can use it as a guide to get your weighting correct and as a reference when diving similar sites/conditions. An entry in my log book might look something like, "7mm full, 7mm hood, 5mm gloves/boots, salt water - Used 28 lbs, try 24 next time"

Happy diving!
 
I would go the other way around. Avoid too much ditchable weight. If you are running 30 pounds of ditchable weight and drop a pocket, you are now 15 pounds positive. You can't fight that to stay down if you are trying to avoid a rocket ride to the surface. By splitting the weight up and having some non-ditchable weight you could loose a pocket and be able to fight to stay down and not be a rocket, but still be able to ditch both if you need to. How much rocket assist do you need to surface?

But as most of this thread went on about, you can probably dial in your diving and get the weight down.
 
I would go the other way around. Avoid too much ditchable weight. If you are running 30 pounds of ditchable weight and drop a pocket, you are now 15 pounds positive. You can't fight that to stay down if you are trying to avoid a rocket ride to the surface. By splitting the weight up and having some non-ditchable weight you could loose a pocket and be able to fight to stay down and not be a rocket, but still be able to ditch both if you need to. How much rocket assist do you need to surface?

But as most of this thread went on about, you can probably dial in your diving and get the weight down.
And that is why I suggested the DUI weight harness. It is ditchable, but will never drop by accident, and it lets you spread your weight around so if you lose a weight it is controllable. I learned this the hard way.
 
Thanks all for your help. Dove yesterday wearing a one piece 7mm w/ Steel 100 and used 20 lbs. Worked perfectly and could go down with ease. Probably can reduce to 18 lbs.
 
Any time my students need more than say 10-12lbs I advise them to distribute it between several systems.
It helps with trim and reduces the chance of a rapid ascent should they lose one of the components.

For example, if they needed 20 lbs, 6 would go in the rear trim pockets (3&3) with an al80, leaving 14 to be accounted for. 8 would go on a weight belt and the other 6 would be divided between the two weight pockets so that in the event one of the pockets would be lost (more common than it should be with certain brands) or needed to be jettisoned, they could still make a controlled ascent.

You rarely if ever need to ditch all your lead. At depth if the BC fails you try to swim up. If you can't, you drop one pocket and chances are that is more than enough for you to start to get positive. Once you start to get positive you keep getting positive.

Lead over a certain amount should never be all loaded in the BC. It makes the rig hard to handle and it risks creating a rapid ascent if the diver doesn't react properly. Some instructors don't know how to distribute lead on a diver. They shove it all the BC because they can and forget about it.
 
https://www.shearwater.com/products/perdix-ai/

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