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Buoyancy Compensators (BC's) and Weight SystemsPoint your weighty "BC" questions and input here. Tell others what you use and what you do and don't like about it etc...
Please note: The last reply in this thread was more than 1 month(s) ago.
BTW, I just uploaded an updated version, which can calculate lift for both weight integrated (lead on rig) and non-integrated (weight belt) BC. There are some substancial differences between the two.
Could someone please explain why the ‘lead on a rig’ is substantial different factor than integrated?
__________________
Everything in moderation, including moderation.
Well, maybe except for fun. Keep in mind, my word choice reflects only my thoughts and opinions and I don't see any reason to not have fun just because something is serious.
Could someone please explain why the ‘lead on a rig’ is substantial different factor than integrated?
Hi,
with weight-integrated BC's you put the lead on the rig - as opposed to the belt around your waist with non-integrated BC's.
That makes the rig heavier and requires more lift for the wing (you don't want BC to sink when you take it off...).
with weight-integrated BC's you put the lead on the rig - as opposed to the belt around your waist with non-integrated BC's.
That makes the rig heavier and requires more lift for the wing (you don't want BC to sink when you take it off...).
I’m not quite following, it seems irrelevant. Removing an integrated, one would drop it? I have integrated and sure not planning to let go of it.
And it is not changing anything with a yes or no.
Also, I’m not quite getting what/how to include gear.
Do I pile everything I’m carrying on a scale and that is my rig?
Mahalo, really appreciate this thing, If I can just figure out how to use it .
__________________
Everything in moderation, including moderation.
Well, maybe except for fun. Keep in mind, my word choice reflects only my thoughts and opinions and I don't see any reason to not have fun just because something is serious.
I often leave the BC floating in the water while I'm putting the fins on. The weight integrated BC with the lead on it requires more lift to stay in float than a non-integrated BC (when I have the lead on my waist).
It's a matter of preference, which type to use.
To add or modify equipment you change input area #1 (blue)
(positive values - for non buoyant stuff, negative - for buoyant (floating) stuff.)
I usually use the "light" field for extra equipment - it does not add to the rig weight.
The spreadsheet is designed with the following goals:
- keep the rig floating on the surface (by itself)
- keep a fully geared diver floating on the surface with the head above the water
- compensate for any negative change in buoyancy while underwater
- be neutral at safety stop
I hope this clears things up, pm or email me if you have any further issues.
Thanks for the feedback!
Quote:
Originally Posted by redrover
I’m not quite following, it seems irrelevant. Removing an integrated, one would drop it? I have integrated and sure not planning to let go of it.
And it is not changing anything with a yes or no.
Also, I’m not quite getting what/how to include gear.
Do I pile everything I’m carrying on a scale and that is my rig?
Mahalo, really appreciate this thing, If I can just figure out how to use it .
__________________
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New York City Doctor Divers .
Youth dive center "Shelf" - Crimea, Ukraine. http://shelfbaby.com/
This is a very nice spreadsheet. Enlightening, to say the least!
One observation: the sample configuration with just 5# of ditchable weight will not cause the diver to become positive at any depth or tank buoyancy other than 3m with an empty tank where the diver would be 5# positive. If the BC fails, the diver will have to swim up and will not have enough buoyancy on the surface to keep his head above water. The only solution would be to ditch the BC and let the wetsuit support the diver.
I need to think about this. Maybe the stainless steel backplate and steel tanks aren't always the best way to go. I seem to recall from training that the idea of ditching the weight belt was to cause the diver to ascend, no matter what.