perils with no dive weight?

[Ayisha]

...If you're correctly weighted, the worst you will be at the surface at the beginning of the dive, is neutral. At the end of a dive with a mostly depleted tank, you would be a little positively buoyant, even if your wing didn't hold air. That's exactly what we want...

Bold added.

I never want to be positive at the end of the dive. If you're positive you're not properly weighted, you can't hold a safety stop or deco stop, and that's dangerous.

Not a fan of the obsession some get (not accusing you necessarily) within the dive industry of using as little weight as possible, which sometimes turns into a dangerous situation of being underweighted. I would always want to be a one pound or two overweight than one pound or two underweight.

Did you miss the part about being neutral or positive at the surface?

My post was directly related to another poster's concerns that he might not be able to be positive at the surface.

Did you also miss the previous paragraph about being correctly weighted, holding the last stop, and making a controlled ascent to the surface?
Not underweighted, correctly weighted.

Did you also miss the original poster stating that he was concerned that he would be a few lbs overweighted when he switches to his lighter exposure protection? Again, not underweighted?

Did you also miss that I stated that a few lbs overweighted is quite manageable?

Please read carefully rather than misinterpret what is written.

 

[UCFKnightDiver]

Bold added.



Did you miss the part about being neutral or positive at the surface?

My post was directly related to another poster's concerns that he might not be able to be positive at the surface.

Did you also miss the previous paragraph about being correctly weighted, holding the last stop, and making a controlled ascent to the surface?
Not underweighted, correctly weighted.

Did you also miss the original poster stating that he was concerned that he would be a few lbs overweighted when he switches to his lighter exposure protection? Again, not underweighted?

Did you also miss that I stated that a few lbs overweighted is quite manageable?

Please read carefully rather than misinterpret what is written.

In the English language, separate paragraphs typically contain related but unique thoughts.

If you're correctly weighted, the worst you will be at the surface at the beginning of the dive, is neutral. At the end of a dive with a mostly depleted tank, you would be a little positively buoyant, even if your wing didn't hold air. That's exactly what we want.

In this short paragraph, you essentially said if you are correctly weighted it is ok ("at worst") to be neutral at the surface at the beginning of the dive at which point you WILL be positively buoyant at the end of the dive. You then followed that up with a "That's exactly what we want." I'm not taking issue with the rest of your post, I'm taking issue with the paragraph/assertion above. I will go a step further and say, you should be slightly negative or neutral with essentially NO air in your tank at the surface at the end of your dive with no gas in your wing. You say you should be neutral at 10 feet, but a slow ascent to the surface from 10 feet is of similar importance to being able to hold a stop at 10 feet in my opinion. Obviously this is getting off topic or away from the OPs original question, but I think it's an important point to make.

And on a separate thought, it's super silly to suggest someone should somehow add buoyant material so they can add ditchable weight. I think this may have been suggested earlier in the thread.

 

[Ayisha]

A balanced rig is when you are neutral or slightly negative at the end of the dive and can reasonably swim your rig up. If you're too negative then it means having redundant buoyancy (drysuit, dual chamber wing, perhaps a lift bag, etc.). A balanced rig does not mean being positively buoyant.

A balanced rig does not pertain to only the end of a dive, and it's not about being able to swim a rig up at the end of the dive, but at the beginning with a full tank in case of wing failure.

The term balanced rig refers to dealing with potential failures on both ends (beginning and end) of a typical dive, not only swimming up from depth.

So, diving with a balanced rig means that in the event of a BCD failure with a full tank, you can swim up your rig, and with a nearly empty tank, you can hold a stop at 3m/10' and make a controlled ascent to the surface.

IOW, not too heavy to manage at the beginning of the dive, and not too light to manage at the end of the dive.

 

[happy-diver]

A balanced diver is weighted for dive conditions, so the ocean can't spit you out if it chooses

Not balanced for a stinking swimming pool, nor any other benign body of water, somewhere

Always negative so the diver is always able to maintain control no matter the seas conditions

and so you avoid hitting your head on the boat

 

[Bob DBF]

And on a separate thought, it's super silly to suggest someone should somehow add buoyant material so they can add ditchable weight. I think this may have been suggested earlier in the thread.

Depends on your objectives.

 

[wnissen]

And on a separate thought, it's super silly to suggest someone should somehow add buoyant material so they can add ditchable weight. I think this may have been suggested earlier in the thread.

Take it for what it's worth, I have only been diving in warm water a handful of times and am fat so even in a skinsuit I still need a few pounds. I read back into my PADI Open Water materials, and it says about weight systems in the very first paragraph, "Regardless of the type, the most important feature is a quick release that enables you, in an emergency, to drop enough weight to float even with an uninflated BCD. This is an important safety consideration so that if you have a BCD problem you could still make yourself float quickly." Establishing positive buoyancy when surfacing is literally the first thing you're supposed to do after checking that you're not going to get run over by a boat.

In calm waters with a boat maybe it doesn't make a difference at all. But if there were any kind of chop, or I might have to be dealing with another diver in distress, I would really prefer to not have to kick to keep my head well out of the water. Or to have to breathe off my reg. Would you want to be fussing with your reg or kicking if you or a buddy were in distress? Yes, it's extremely unlikely to have a simultaneous failure, so it may be a risk, like Angelo, that you're willing to take.

A few pounds, for me, is not a big deal to carry. Or maybe a slightly buoyant non-backplate BCD is more appropriate in this situation. (I know, they'll probably kick me out of Scubaboard.)

 

[boulderjohn]

Regardless of the type, the most important feature is a quick release that enables you, in an emergency, to drop enough weight to float even with an uninflated BCD.

Speaking as a PADI instructor, that supposed ideal is very hard to attain in many cases. I have had many OW students in pool sessions who will sink with a 3mm wetsuit even without any weights. When PADI added the emergency weight drop to the OW course, I asked headquarters what I should to with students who have little to no weight. Their solution for this skill was to have them do the exercise with a weight belt that was not theirs. I know of no recommendation anywhere in PADI (or any other agency) to add buoyant material to make ditchable weights a requirement.

And then there is technical diving, which is really where the idea of a balanced rig started. There is no way you can have a set of Worthington LP 108 doubles on your back and achieve that level of ditchable weighting. So what does PADI recommend for that? Redundant buoyancy. When carrying that much non ditchable weight, they recommend that you have an additional source of buoyancy, like a drysuit. Some agencies do not allow instruction with steel tanks without that. In PADI tech classes, students are required to do some of their diving using only their redundant buoyancy for floatation. Another possibility is a dual bladder wing, which would allow you to add air to the wing even if the main bladder is breached.

When I was training to be a TDI tech instructor, I similarly had to demonstrate the ability to do a controlled ascent using a lift bag.

 

[UCFKnightDiver]

Take it for what it's worth, I have only been diving in warm water a handful of times and am fat so even in a skinsuit I still need a few pounds. I read back into my PADI Open Water materials, and it says about weight systems in the very first paragraph, "Regardless of the type, the most important feature is a quick release that enables you, in an emergency, to drop enough weight to float even with an uninflated BCD. This is an important safety consideration so that if you have a BCD problem you could still make yourself float quickly." Establishing positive buoyancy when surfacing is literally the first thing you're supposed to do after checking that you're not going to get run over by a boat.

In calm waters with a boat maybe it doesn't make a difference at all. But if there were any kind of chop, or I might have to be dealing with another diver in distress, I would really prefer to not have to kick to keep my head well out of the water. Or to have to breathe off my reg. Would you want to be fussing with your reg or kicking if you or a buddy were in distress? Yes, it's extremely unlikely to have a simultaneous failure, so it may be a risk, like Angelo, that you're willing to take.

A few pounds, for me, is not a big deal to carry. Or maybe a slightly buoyant non-backplate BCD is more appropriate in this situation. (I know, they'll probably kick me out of Scubaboard.)

There's not really a situation that I can think of where I would recommend trying to add some sort of buoyant material so that you can then add ditchable weight. Essentially you're trying to go from being negative, to being positive, to then adding ditchable weight to be slightly negative again. Additionally, most buoyant material such as foam is going to compress at depth, so that the additional weight you added will eventually overcome that added buoyancy. If you are adding lead weight to the rig though, then it could make sense to make at least some of the weight ditchable.

What PADI should really say is that if you need to add weight, it's not a bad idea to be able to ditch that weight. And they should add, if you're super negatively buoyant, you should examine your gear choices to make sure your rig is balanced. Some of those gear choices could be a steel vs. aluminum backplate, steel vs. aluminum tanks. You could also consider using a redundant form of buoyancy such as a drysuit, a dual bladder wing, or carrying a lift bag, etc.

 

[Jim Lapenta]

This season I am going to be doing some fun diving at a local spot with weights and no BC. Using my 5mm free diving FJ suit, backpack and al80 or steel 72 depending on what I have filled. Worked with it in the pool last summer and over the winter. I might borrow a friends double hose since that was what I practiced with several times. Plus the camera to shoot some awesome bluegill nests.

 

[wnissen]

Speaking as a PADI instructor, that supposed ideal is very hard to attain in many cases. I have had many OW students in pool sessions who will sink with a 3mm wetsuit even without any weights. When PADI added the emergency weight drop to the OW course, I asked headquarters what I should to with students who have little to no weight. Their solution for this skill was to have them do the exercise with a weight belt that was not theirs. I know of no recommendation anywhere in PADI (or any other agency) to add buoyant material to make ditchable weights a requirement.

I know that you did not control the PADI response, but that is one of the dumber things I have ever heard. I guess the students, who won't customarily be wearing weight belts, would, in case they wear one, be familiar with the skill?

The rest of your post is interesting as well. I see that the magnitude of the weight would be much greater with a set of doubles, so it makes sense that you would carry a spare inflatable buoyant something if you didn't have a drysuit. Presumably there's no one out there so bony and muscular that they are 10 pounds negative...