Larger BC, more weight?

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Some things aren't adding up for me here. I saw some posts on doing a proper weight check, and I would recommend this as well. Just going to add a few points.

27 lbs with a steel 100 sounds really high to me. However, you are also using a much thicker wetsuit than I'm familiar with, so it's possible that's what you need. For the sake of discussion, your lift needs to be sufficient to offset your total ballast. I'm assuming that you are able to at least establish neutral buoyancy at depth. If that's the case, that's a data point indicating that your lift is not undersized. That said, with the amount of weight and the negative properties of the steel, you may be really close. Your exposure suit offsets some of the weight at the surface, but that goes away at depth with a wetsuit. How full is the wing when you first get to the bottom and establish neutral. If it's full, or nearly so, you may need a larger wing for that given weight.

Since you said wing, I'm assuming BP/W or at least rear-inflate. No matter how large the wing is, it will never be able to float someone during a surface swim without using a snorkel or regulator. Assuming we aren't talking about backstroke, the lift is all on the diver's back, so at most the back will be at the surface, but everything else underwater.

You really need to do a weight check at the end of your dive during a safety stop. At this point, your tank is closer to empty, your wetsuit has re-expanded. So in other words, you'll be at your most buoyant at this point. Your wing should be empty, or nearly empty. If it's not, there's some weight that can be shed.

If your dive count in your profile is correct, being overweighted is pretty much expected. A lot of instructors teach with their students overweighted as they feel it's easier that way. Also, it's a normal tendency for a newer diver to hold a bit more air in their lungs. This will get better with time.
Thank you for your contribution.
Yes, neutral buoyancy at depth is no problem. Once I drop and get down to depth, I give my BC no more than 2-4 quick air shots and I'm good. The rest is breath control and my lungs. Yes, it is a BP/W setup.
To add additional clarity, I was talking about backstroke on the surface. The 32# did not do well getting me out of the water, but my WTX-D40 is sufficient to accomplish out of the water backstroke surface swimming.
At safety stops, my wing is empty or pretty close to it.
 
Thank you for your contribution.
Yes, neutral buoyancy at depth is no problem. Once I drop weight and get down to depth, I give my BC no more than 2-4 quick air shots and I'm good. The rest is breath control and my lungs. Yes, it is a BP/W setup.
To add additional clarity, I was talking about backstroke on the surface. The 32# did not do well getting me out of the water, but my WTX-D40 is sufficient to accomplish out of the water backstroke surface swimming.
At safety stops, my wing is empty or pretty close to it.
Perfect. Sounds like then you are probably as close on weighting as you need to be. 27lbs of lead and a steel tank will be pretty close to the wing lift capacity. Especially if that 27lbs is on top of the backplate itself. Larger wing definitely sounds like a good idea then.

For comparison, I dive in much warmer waters, so thinner BC at most. I use a back inflate BC with 35lbs of lift. The most weight I use is 8lbs, but 6lbs is generally sufficient. Adding this just to show the delta between lift and ballast in the two cases, not to compare my weight needs in warm water to yours. Weighting needs are individual.
 
How new is the neotek? I bought one a few years ago, when new it took 28 lbs (it was a 3x) and after 10 dives or so it took 18 lbs to sink.

With weighting it always takes what it takes.
 
How new is the neotek? I bought one a few years ago, when new it took 28 lbs (it was a 3x) and after 10 dives or so it took 18 lbs to sink.

With weighting it always takes what it takes.
The Neotek2 is phenomenal. I dove a standard 7mil wetsuit during my certs and got cold towards the end of my second dives. The integrated hood keeps things nice and snug. The baffles inside and fit with the 2XL keep water out. Even when a bit sneaks in because of my head turns, it never gets very far. The metal rings in the cargo pockets are perfect for attaching my GoPro and spare mask. This thing is winning all around.

I never thought that I would be spraying baby soap all over myself at the beach, but it's needed to get inside :-) Highly recommend the NeoTek2.
 
The Neotek2 is phenomenal. I dove a standard 7mil wetsuit during my certs and got cold towards the end of my second dives. The integrated hood keeps things nice and snug. The baffles inside and fit with the 2XL keep water out. Even when a bit sneaks in because of my head turns, it never gets very far. The metal rings in the cargo pockets are perfect for attaching my GoPro and spare mask. This thing is winning all around.

I never thought that I would be spraying baby soap all over myself at the beach, but it's needed to get inside :) Highly recommend the NeoTek2.
It’s ok, try a dry suit.

My point is the weight requirements will likely change as the suit breaks in.
 
It seems like I found my setup for saltwater. I'll be diving two cold freshwater lakes next week, but dropping 3 pounds or so.
If you're using the same suit & tank, you should drop about 7 lb going from salt to fresh. (This comes from the 2.4% difference in average water densities times the total mass, incl. you, tank, lead, etc.)
 
Just like in other places, PNW dive schools regularly put excess weight (here ~30 lbs) on students/customers, it's just easier/faster to sink the clients than to train them in the proper skills. There just isn't time. It would take several more focused dives to do so.

My point is that if he sets his weight so that the BC needs to be dead empty in order for him to hold his stop there will be times when that won't be enough to let him do so.
And yet, the full dump / weight dump / lie on bottom or crosslegs drill protocol always seems to be a net benefit.

Many people can drop a couple of bricks this way, and still have no trouble holding stops after that--if their other skills (trim, control etc) are adequate.

You are not critically underweighted until your BC/wing/suit are empty, you are holding your fins or laying on the bottom, and you still can't take a normal breathe without surfacing. Few are doing that actual test.

People used to dive without BCs/wings. A few purists still do

It's not a competition to use less weight. I see divers who can't hold the safety stop as underweighted. I can pull them down though.

Am I overweighted? Well you have a BCD to compensate. Better to have more weight that not enough.
People losing their stops often have poor BC/wing/suit dumping skills, poor management of residual air spaces, or poor trim & technique, rather than being underweighted. Adding weight as a 'fix' would be a mistake, unless done temporarily to ease skill development.

Overweighting is commonly done for sinking students/customers with undeveloped skills to save time, and then never corrected.

More weight = more residual air spaces, holding depth is harder due to expanding/contracting in proportion to volume with minor depth changes. Underwater profile bigger since the wing is partway full, increasing drag. Harder time swimming up if there is a BC/wing failure. Less buoyant at the surface. May need to ditch the extra weight, rather than being properly weighted enough that this is unnecessary. More encumbered/cluttered/setup on the surface.

I would guess that far more 'bad diving' and more diving accidents have occurred due to overweighting, rather than underweighting. It is actually quite rare for someone to be diving truly underweighted. Most err on the side of more weight, and then blame other issues on being "underweighted."

Instructors/guides can attest, on almost every single group/boat dive, there is a general-level diver who can't even descend when properly weighted, because they don't know how to dump, stop kicking and breathe out.

The ~3-4 lbs of air that they consume on the dive is almost never going to be the causative issue.
 
I’m a new OW diver trying to figure out optimal weighting and buoyancy. I am 6 feet tall, 245 pounds with around 15% body fat. I’m diving in salt water with a Neotek2 8/7/6.

I bought a 32# wing which doesn’t seem to lift me out of the water enough for a surface swim without a snorkel or using my air. With that said, towards the end of my dive, I can’t seem to stay down with an empty BC and 27 pounds of weight with a steel 100.

I’ve used several calculators and methods to figure out weighting; they vary from 24-27 pounds. Based on the data I have experienced while diving, it seems like I need another three or so pounds and larger single tank wing than 32#. Thoughts or recommendations?


Currently about same height/weight with a little more body fat.

Hearing you’re at almost 30 pounds is intriguing, but like most have said, as a new diver they overweight you in training and that’s all you know, plus the saltwater additions.

What BCD are you running? Any accessories? Faber HP100? Curious to know what your actual weight is loaded. Do you have a hand scale at home to weigh your BCD dry?

I’m running a BPW (30# Deep6, steel plate), two orca torches plus my octo/regs..and if I even look at lead, I sink like a rock unless I’m in a 5/4, which I have to add around 2-4 pounds (fresh). I understand saltwater and adding, but it sounds almost dangerous if you are unable to fin all that extra weight if something fails, or you’re so heavy you cannot remain surface swimming.
 
I'm another large frame diver. Couple years ago on entry I couldn't relax. This had me breathing deep, and retaining a lot of air in my lungs. Now on entry I find my happy place, and can easily breathe off the bottom or the top of my lungs depending on where I need to go. Using the same rig as a few years ago, but now with a smaller wing I've now dropped 8 lbs of lead and can easily dive a pair of AL80s on an 18lb wing and 6 lbs of lead.

Just use what weight you need, and gradually you'll be able to relax at the beginning of the dive.
 
This dude is a similar size

jason-mamoa-mc-221118-768cfd.jpg


My younger self was a similar size, still sort of am sort of

Way way into the morbid obesity range. You need to address this or you'll be looking at problems far greater than needing more weight in your BCD.

Best you trade in your Global Body Mass Index Warming book for the truthful amended version dude!
 

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