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Thread: Weighting Query

  1. #1
    Purine hurts my feet Major Clanger's Avatar
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    Weighting Query

    Can anyone see any issues including the weight of bailout and deco cylinders as part of overall weighting requirement? I get the need to not include removable equipment as part of basic weighting, so, if I don't plan to ever remove the cylinders underwater, is the any reason why they can't become part of my basic weighting? Clearly I'd need to allow for their buoyancy on minimum gas and buoyancy according to gas type eg 50% being more neg than a mix etc.
    GaryL

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    Charlie SoggyBottoms's Avatar
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    what about when you need to hand off the cylinders?
    regards, Charlie

    charliesez http://tinyurl.com/bjjus8g

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    Moderator GLOC's Avatar
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    If you dive the team bailout/support strategy, Charlie's point is valid. Even more important is that if you are handing off that stage, it could be anywhere upto 3kg if you are handing off an AL80 of 50% or 80% (nitrox rather than Trimix).

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    Purine hurts my feet Major Clanger's Avatar
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    Rtfq The bit where I said if I plan not to hand them off...
    Last edited by Major Clanger; 13-01-2013 at 01:44 PM.
    GaryL

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    Established TDF Member Barrygoss's Avatar
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    Weighting Query

    So your bail of 15/50 is all used up and has gone positively buoyant. What do you do? Bag it off... but you can't do that because it started a couple of kg's negative and is part of your weighting......
    Stages shouldn't be part of the weighting.
    B
    Rebreathers are like women; they pretend to love you, whilst taking all your money and trying to kill you.

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    Closed Account: User Requested nickb's Avatar
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    You need to consider the effect of breathing them down. Ali80s are slightly positive once breathed empty, even with a regulator fitted. I've sent on up an SMB line before, which is essentially the same as not having one, so do the maths

    [EDIT] Baz got there first!

  7. #7
    Purine hurts my feet Major Clanger's Avatar
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    Quote Originally Posted by Barrygoss View Post
    So your bail of 15/50 is all used up and has gone positively buoyant. What do you do? Bag it off... but you can't do that because it started a couple of kg's negative and is part of your weighting......
    Stages shouldn't be part of the weighting.
    B
    And if your bail was in a steel cylinder...
    GaryL

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    Closed Account: User Requested nickb's Avatar
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    Quote Originally Posted by Major Clanger View Post
    And if your bail was in a steel cylinder...
    You'd still lose the weight of the gas, which would be the same.

    This is basic stuff.

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    Established TDF Member Barrygoss's Avatar
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    Weighting Query

    Quote Originally Posted by Major Clanger View Post
    And if your bail was in a steel cylinder...
    What size? What gas? I'll run the maths to find out just what the swing will be
    Rebreathers are like women; they pretend to love you, whilst taking all your money and trying to kill you.

  10. #10
    Purine hurts my feet Major Clanger's Avatar
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    Quote Originally Posted by nickb View Post
    You'd still lose the weight of the gas, which would be the same.

    This is basic stuff.
    Nick I did acknowledge in the OP allowance for minimum gas in the cylinder.

    If I use a steel cylinder for bailout and I've based weighting to include its buoyancy when empty I don't see any reason not to include it which is why I've asked if I missed anything else. Please assume I know the obvious
    GaryL


 
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