Disadvantages of not having any weight to ditch?

[CamG]

Greetings RD and I think the things to consider have been discussed quite well.
This being said I have done dives without weight and I have had issues before.
One was wing failure that I simply used my dry suit to float my 95's..
Had the DS not been enough the lift bag on my plate would have taken care of it.
In one word REDUNDANCY!

If you are diving this rig all the time it would be wise to train for and expect failures so if and when one occurs you are ready!
Careful consideration and dive planning need to be a part of every dive!
I personally enjoy diving weighted perfectly and it can be magical!

CamG Keep diving....Keep training....Keep learning!

 

[dreamweaver21]

The important point is whether you can swim the rig up from depth where a wetsuit will loose buoyancy due to compression. With a jacket BC, AL80, and no lead you should be fine - even if you have a lot of metal in your bones

However, when you trade the AL80 for a steel HP100 (or something even more negative) and stay in a wetsuit you will be most likely at the mercy of a functioning BC with no redundancy and no means to escape BC inflation failure.

The goal is to have a 'balanced rig' that satisfies two important requirements:

• You can hold a safety stop with nearly empty tank(s)
• You can swim up with full tank(s) in case of BC failure

Sometimes that requires ditchable weight, sometimes it does not.

I did exactly that last year. I bought steel HP100s after diving AL80s for a couple of years. With the AL 80s I just had a few pounds of lead in my weight integrated BC. I have only dove the steel 100s with a full 5mil so far but even with the full 5mil and no lead I was heavier than I was used to at the begining of the dive and normal at the end. When it warms up and I am in a shorty, I think I am going to leave a mushroom cloud on the bottom of the sea floor when I hit.

 

[LeadTurn_SD]

So how would a person who is naturally negative ensure that they have weight to ditch. For example, when I was doing my checkout dives I was diving a jacket bc, al 80, and no weight and negative throughout the whole dive. Yes I could carry weight, but what good would it do me if I naturally sink anyways. How do you get around the conundrum of not having ditch-able weight in this case?

Lean folks in thin or no exposure suits will often not require any ballast weight. As long as they can swim their rig to the surface (as already mentioned) and remain at the surface with a full tank and empty BC (not mentioned enough), it is ok.

If either of those conditions cannot be satisfied, then a lighter rig is needed, or an alternative form of "flotation".

For a recreational diver, you need to be return to the surface without assistance, and then be able stay at the surface once you get there (again without assistance). It is really that simple.

If you have doubts, you can always test your ability to do both in a controlled, non-emergency setting.

Best wishes.

 

[Lobzilla]

I did exactly that last year. I bought steel HP100s after diving AL80s for a couple of years. With the AL 80s I just had a few pounds of lead in my weight integrated BC. I have only dove the steel 100s with a full 5mil so far but even with the full 5mil and no lead I was heavier than I was used to at the begining of the dive and normal at the end. When it warms up and I am in a shorty, I think I am going to leave a mushroom cloud on the bottom of the sea floor when I hit.

Here are some calculations that show how to determine your weighting/buoyancy and identify potential problems. YMMV as far as the exact numbers are concerned but you can see in the third example why steel tanks and wetsuits are generally not a good combination.

By comparing the first and second example you can see how I improved my odds at depth by shifting weight from the backplate to my weight belt/pouches.

(I dive a lot of different configurations like singles, doubles, steel, aluminum, wetsuits, drysuits, minimal undergarments, 'polar' undergarments, etc. To make the correct weighting manageable, I determined the buoyancy of each listed item in the pool with a luggage scale. The "diver plus exposure protection" item is determined by figuring out how much weight I need to barely sink, not wearing the rig and using the long hose as a hookah. Salt water buoyancy can be calculated via ((DW+FB)*1.027)-DW where DW is dry weight, FB is fresh water buoyancy, and assuming that salt water density is 1.027)