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Need a question answered

Discussion in 'DIR Diving' started by stevehusauk, Jun 24, 2017.

  1. Wibble

    Wibble Fish don't talk
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    Sorry, you're wrong.

    Firstly, I'm agreeing with all your comments about twindies. Main issue is practising and following the protocols to switch regs to balance gas usage.

    The *standard* twinset longhose primary donate works exceedingly well and absolutely excels when deco gasses are involved. The donate is whichever reg you're breathing from: no thinking, just grab the reg in your mouth, duck your head and donate, then scoop up the necklaced backup just under your chin. It's a completely automatic procedure taking less than a second.

    It's so effective that all agencies accept this as *the* standard configuration for diving with twinsets, and pretty much mandate it for technical diving with twinsets. Sorry, that's all agencies except BSAC.
     
  2. Tel

    Tel Super Moderator
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    FFS Wibs do you read posts before hitting the keyboard? This is a thread about indies.
    The standard PD long-hose config as used on manifolds ARE a total CF on indies with
    incompatible protocols.
     
  3. Mako-JD

    Mako-JD Active Member

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    So both primary and secondary are worn with necklace ? over right, and donate is clipped to left side with standard size hose.
     
  4. Tel

    Tel Super Moderator
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    Well you can do it that way with a necklace, I prefer to have 1 & 2 over right shoulder, but use the hose clip on my shoulder,
    so when I swap I just press the one that i'm not using in the clip. It's stupidly simple and works very well.

    Donate/alternate comes under arm left and hose length is down to you, but if using a long hose it's easy to stow.
    Remember by putting the SPG hose under the arm and shoulder strap nothing is on the left apart from the alternate, so the hose can
    be felt from where it's stowed.
     
  5. stevehusauk

    stevehusauk New Member

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    If your a local diver we may know each other if your over 40


    Sent from my iPhone using Tapatalk
     
  6. timmyg

    timmyg Super Moderator
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    Gents, calm down FFS, the OP answered a genuine question. There's no need for handbags at dawn. And Wibs, it was not too long ago that you would have been asking these types of question.

    Firstly, @stevehusauk, there is no wrong, unless something is downright dangerous. There's just a difference of opinion and training.

    As previously stated, the most common way, and the way that has been adopted by the majority of technical agencies, is to use a manifold. However, there are times when twindies may be preferable. Arguably the choice is yours, and each setup has had their pros and cons shouted from the roof tops so I won't repeat. Regardless of which setup you use, the standard is one first stage and one second stage per cylinder. There is no requirement for three or four, and again this has been mentioned.

    With regards to twindies and reg source, as Tel said, traditional AS secondary take would work well, however I disagree that PD is a total CF. If that were the case it wouldn't be one of the most popular ways to configure side mount. The only difference between PD on twindies or manifolded is that the clip has a breakaway on it (such as an o-ring). So to donate if breathing primary, no change to normal. To donate if breathing backup, grab primary and donate as normal. The breakaways will give out. An alternative method is 2 regs on a necklace which some side mounters do also use.

    With regards your comments about slob knobs, yes some people dive them but it's a sticky plaster on a bigger issue. I bet that I could shut down just as quick, if not quicker without one. It's down to technique and practice. Please consider that this is coming from someone who has dived PD with hog loop, PD with bungeed hose, secondary take, OPH, harness with a break, bungeed wings, slob knobs, twindies etc... before settling on my hogarthian rig. Unfortunately it has cost me a lot of money, but at least I can speak from experience. That is why I am keen on educating people on buying the right kit first time round. But again remember, there is no wrong, unless something is downright dangerous. There's just a difference of opinion.

    Regarding the comments about OOG in 30 seconds, there's a useful video here and article here. At depth (40m) the rough times are approximately 2 mins for a LP hose and 22 mins for a HP hose (based on a full cylinder).

    If you've any questions for me please do ask. I'll probably not get involved in the tit for tat arguments.

    TG
     
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  7. Wibble

    Wibble Fish don't talk
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  8. stevehusauk

    stevehusauk New Member

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  9. stevehusauk

    stevehusauk New Member

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    What a shame there are some arrogant guys in here genuine question followed by bs egos . Been diving 30 years seems you all think its impressive to play one up


    Sent from my iPhone using Tapatalk
     
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  10. Tel

    Tel Super Moderator
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    The standard long-hose is just a that a SINGLE long hose and the necklaced effort is a funnily enough a short hose.
    On manifolds the diver donates, switches to necklaced everybody is happy, they sort out the fubar or go home. For this
    system and especially when mix gas is used and by that nature (hopefully) more experienced divers its A1, no question.

    So what happens with indies? The same system will see at times the primary (as above) and that's absolutely fine, but for
    a percentage of the dive the primary has now become the alternate and it's short house time again.

    Ok so you can mitigate this by having two long-hoses, well imagine the fun with that :)
    Or you can come up with a plan that just works.

    PD works because the protocols are the same each and every time as hopefully is the config.
    On indies the same is a CF because both the protocol and the config has changed and it's a gamble as to which one the
    diver needs to use right now.

    Three regs work because it's not reliant on the config of the two primaries. Whatever reg you have in your mouth makes
    no odds as the protocols with a stand alone long-hose is the same. No doubt, no mess, no thinking, just the same action
    and response again and again.
     
  11. stevehusauk

    stevehusauk New Member

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    Ps great video 3000 psi down to Zero but lower cylinder pressures lower volumes fully supports redundant air supplies



    Sent from my iPhone using Tapatalk
     
  12. hawk

    hawk Doing It Rong
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    Oddly I'm going to agree with Tel here re 3 regs on twindies - it does make sense (if you look past the additional point of failure).

    And, for the sake of argument, I'll assume you don't need a long hose for the sort of diving you are doing (e.g. not single file wreck / cave) BUT I still advocate a long hose and donate when diving twindies or SM.

    I have posted on here plenty of times on my views and, as Tim has said, there is a reason why it is the favoured config.

    Personally, I swap regs more frequently than Tel suggests but the principle is the same and ensures that (if I have done my gas planning correctly) I will always have enough gas to get me and a buddy to the surface.
     
  13. Tel

    Tel Super Moderator
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    An additional failure point? Yes true if looked at in reg terms, but as we've lost the failure points of the manifold, reckon it's even :)

    Depends on the type of diving sure, but yes one of the reasons for the SPG under the arm/shoulder strap is to give a clear side for the
    alternate, so a long hose can easily be configured, stowed and deployed cleanly.

    The biggest problem with indies tends to be those that dive them rarely, say when they don't have a lot of choice. It's understandably
    that a diver who uses manifolds, has a mindset that the standard PD config works and for them even a slight variant in memory
    skills feel alien so will adopt the same config regardless. If however the diver only uses indies then it makes sense to come up with a config
    and protocol specific to them. Where is the logic in using a protocol from a different system with key elements that are different?

    Yes this is really for the typical mid-range dives and standard slack times where 240 bar is the norm. It also makes for easy explanations
    with the maths :) Of course that 80 is an arbitrary figure, still has to be a calculated reserve.
     
  14. timmyg

    timmyg Super Moderator
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    Sorry Tel I do disagree, but each man to their own. A traditional hog works fine on indies. If it was such a CF it would not be taught as standard on most SM courses, and I know plenty of divers who use it with no issues. You always grab the long hose, wether it's in your mouth on your right shoulder.

    TG
     
  15. hawk

    hawk Doing It Rong
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    I've said on here (many times before) that I run a yellow reg on my long hose and that it has never confused anyone - it's pretty simple really GRAB THE YELLOW ONE.

    However, I really do fail to understand what all of the fuss is about for 2 reasons:

    1 - whichever reg I have in my mouth will work and if anyone grabs it, I can sort myself out without bother (the necklaced reg will break away if pulled). Once everyone is breathing again, we can swap if needed

    But mainly because

    2 - I consider myself to be a reasonably competent and aware diver and have never had anyone who is OOG (either RL or simulation) get anywhere near me without me having presented an alternate (whatever that may be)
     
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  16. Tel

    Tel Super Moderator
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    It's simple really. PD is cited as the ultimate one stop solution for manifolded twins diving with a tried and tested
    same protocol adopted by all the tec agencies and called optimum by at least two :)

    This system has many advantages and if it has a known flaw that's confined to new and very inexperienced divers who
    seeing as it's king in the tec world can be dismissed as not being that relevant. So (hopefully) we can all agree that
    long-hose PD is the way to go if you twin up with manifolds.

    The above though does have an Achilles heel and that;s primary take. We know that those that are schooled in
    PD will have a memory skill to say take the donated reg, the one that was in the guys mouth. We also know that a diver
    gasping for air will usually revert to training and instead of waiting for a donate could well grab. With standard PD this is
    NOT an issue because A) The long hose is the one in the mouth and B) Those taught PD have been taught that PT is a
    possibility, reg goes switch to necklaced no big deal.

    Trouble is that with indies the same doesn't apply. Now in a PT situation depending on what gas management routine is
    being used a large percentage of the time Diver 1 will have the necklaced reg in the mouth and in the case of PT the
    OOG diver taking the reg from Diver1's mouth will now be faced with a reg that may or may not come away clean and
    even if it did may not have enough hose length and could even end up being used upside down. If that's not a CF in
    waiting then don't know what is :p
     
  17. Wibble

    Wibble Fish don't talk
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    It'll only be upside down because it's on a short hose or the person's not turned it round the right way.
     
  18. Tel

    Tel Super Moderator
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    "the OOG diver taking the reg from Diver1's mouth will now be faced with a reg that may or may not come away clean and
    even if it did may not have enough hose length and could even end up being used upside down".



     
  19. Wibble

    Wibble Fish don't talk
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    Therefore use a longhose and there isn't a problem. Put a yellow reg on it and it's unambiguous: "take the yellow one, even if I give it to you".

    Then you've some space to use whilst you're sharing gas; putting up the bag, sorting out the person's rig, whatever.

    Just like the sidemounters do.
     
  20. Tel

    Tel Super Moderator
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    Yeah already do that, it's on the third reg, which has a yellow face, a yellow long hose and is dedicated to one role
    from a cylinder that always has the most gas - did you forget about gas management?

    Can't get more unambiguous then having a single protocol to grab the same reg no matter what :)
     

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