Doubles, Weight and Dry

[ucfdiver]

WHAT!? Ditchable weight is for beginners.

neareas doesn't understand redundant bouyancy, which is sad, seeing how he's now calling out myself and other posters, as well as their instructors without this knowledge. He's wearing more non ditchable weight than the people he's calling out, which is the funny part about it.

 

[TSandM]

I'd hate to have to ditch weight to establish neutral buoyancy. I always thought ditching weight was a way to achieve POSITIVE buoyancy, which is precisely what is wrong with doing it anywhere other than the surface . . .

 

[LavaSurfer]

I'd hate to have to ditch weight to establish neutral buoyancy. I always thought ditching weight was a way to achieve POSITIVE buoyancy, which is precisely what is wrong with doing it anywhere other than the surface . . .

It is in my book!

The way I typically dive, deep and long, ditching weight isn't much an option.
In fact if I have to ditch weight it was bad planning or a serious emergency and bolting to the surface probably is still a bad idea.

I am comfortable with or without the ditchable. As I said, I am just planning all the contingencies and avoiding the folly of a dirt dart to 90 feet into the mud. I feel I have a solid plan for the next steps and am comfortable with it. Once I get the weight dialed in and logged in several different configurations and garments then I can concern myself with where I want to place the weight. More than likely, if its needed it will be on my back in pockets placed to adjust trim.

Ditching weight to become neutral makes no sense to me either. It is a last ditch effort at the surface and I view it again as really bad planning and unfamiliarity of your gear and requirements. This is why i am doing this now and not on the bottom where it is an emergency.

 

[Web Monkey]

Ditchable weight is good and I like the idea but I was more concerned with contingencies. Lets say I were into the dive a few minutes and I have a failure in the wing, I have my drysuit, but can it get me up while swimming?

Unless it's way too small, your drysuit has enough airspace to send you to the surface much faster than you want to go.

Terry

 

[JeffG]

Ditching weight to become neutral makes no sense to me either.

On paper it makes sense. Assumption: You start the dive negative, equal to the weight of the gas on your back

Now, lets say you have a weight belt that is equal to that same amount.

If you have a catastrophic BCD/buoyancy failure at the start of a dive, you are at you most negative state...but you also have no decompression obligations.

Drop the weight belt and you should be around neutral and should be able to get out of dodge.

If you have a catastrophic BCD/buoyancy failure at the end of a dive, you should be around neutral, so you should be able to do your decompression obligations without ditching your belt, but also shouldn't be a state where you are not dirt darting it to the bottom.

Now, having said that. In practice it is tough to get a system to do fit that system. Double Alum 80's and a drysuit come very close. Double 130's in fresh water...doesn't.


adding weight to a weight belt just to make "it" ditchable on a very negative rig (double 130's with a SS plate for instance) is just stupid. It means someone took a "rule of thumb" and applied it incorrectly.

 

[nereas]

neareas doesn't understand redundant bouyancy, which is sad, seeing how he's now calling out myself and other posters, as well as their instructors without this knowledge. He's wearing more non ditchable weight than the people he's calling out, which is the funny part about it.

As I said before, if you are diving with no ditchable weight, then you are simply permanently overweighted and unsafe. Enought said.

"Are you sure you want to add ucfdiver to your ignore list?" Definitely!

 

[nereas]

I'd hate to have to ditch weight to establish neutral buoyancy. I always thought ditching weight was a way to achieve POSITIVE buoyancy, which is precisely what is wrong with doing it anywhere other than the surface . . .

This is what beginners are first taught. Eventually this notion of "establishing positive buoyancy" needs to be outgrown. Positive buoyancy is nice once on the surface, but underwater it can be a major hazard, as I am sure you can imagine.

 

[LavaSurfer]

This is what beginners are first taught. Eventually this notion of "establishing positive buoyancy" needs to be outgrown. Positive buoyancy is nice once on the surface, but underwater it can be a major hazard, as I am sure you can imagine.

nereas

Please give an in depth view of buoyancy as you see it.
What you are saying is not making sense to me at all and maybe I am just missing something.

if you are diving with no ditchable weight, then you are simply permanently overweighted and unsafe

Are you inferring that at the front of the dive you are over weighted due to the inability to ditch weight at the beginning of a dive? If so, I see where you are coming from although I tend to disagree if I have alternative means of buoyancy control in case of a failure, redundancy is king here. I know many people that would never be able to dive doubles and possibly AL80s in FW if the general rule was no diving unless you can ditch weight and achieve neutral without the aid of a BC device. Some people sink no matter what.

Ditchable weight and being over weighted are two separate issues, I cannot get my head around why you want to make them one. I can dive perfectly weighted without ditchable weight and likewise I can be seriously over weighted with lots of ditchable weight . The two just are not related at all in this context.

For example, in SW I use my SS wing and 4 lbs on the straps with a 3mm shorty. at the end of the dive, 500 lbs in an AL80 I am slightly negative. at 300 lbs I am neutral and at 100 lbs I need a rope to stay down. That is, perfect weighting for me. NOW, the weight is not ditchable per se, Yes I could take it off the pouch and then drop it but it is not on a belt. I could however move that weight to a belt and make it ditchable. doing so would not effect my buoyancy in the least, it would only F up my fine tuned trim. so I am curious how you are tying the two together.

 

[ucfdiver]

This is what beginners are first taught. Eventually this notion of "establishing positive buoyancy" needs to be outgrown. Positive buoyancy is nice once on the surface, but underwater it can be a major hazard, as I am sure you can imagine.

Let's say I'm doing a dive that requires steel 130's, and I'm wearing a drysuit, and do not require any extra weight to be negative.

Do you suggest that I
-Not do the dive since I'd be negatively buoyant?
-Add dropable weight?

 

[nereas]

Alternative buoyancy is fine, so long as you understand the situation that you are in. However it still makes little sense failing to wear a weight belt, and failing to load that weight belt with the amount of weight corresponding to the volume of your breathing mix multiplied by 0.08 lbs per cu ft. Thus you then and only then have the option to ditch the belt in the early stages of the dive, in case your buoyancy wing (or suit, or both) fails, thus being able to establish neutral buoyancy at that point.

Having such a weight belt also gives you the ability to establish positive buoyancy at the surface after the dive, as well, should the wing and/or suit fail.

There is simply no reason to omit these standard precautions, and diving without any ditchable weight is simply dangerous and negligent. I muted Jeff a long time ago because of his nonsense posts, and today I added ucf to the list. In this way, I do not waste my time on negligent dangerous divers.