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Bailout rebreather?

Discussion in 'Rebreather Diving' started by Thrutch, Apr 5, 2021.

  1. marsh9077

    marsh9077 Contributor

    # of Dives: I just don't log dives
    Location: Australia
    344
    289
    the Triton does not have a solenoid. Its a manual ccr, O2 is leaked into the loop via CMF orifice feed from a Apeks DS4 with a blanking plug. ADV is activated to keep the loop full of whatever diluent your using for the depth your diving this way there is always breathable gas in the unit and as you do dil switches you flush dil through your BO unit also to keep matching dil your primary is on. If you do have to switch to your BO unit you then adjust CMF accordingly to the SP you want, also can use MAV to help make adjustments especially on accent.

    But like I said earlier there are tons and tons of different trains of thought on BOB and I can't really say what way is correct and what is wrong. Many people just experiment and find out what works best for them and there diving style or have learned from someone and just dive a BOB that way because its how they were shown. There are not formal trainings or course on BOB. If your doing dives that required a BOB then you already are very aware of the risk involved and there are many different ways to execute a dive like.
     
    evandroairton likes this.
  2. Heat Miser

    Heat Miser DIR Practitioner

    # of Dives: 200 - 499
    Location: Perth
    117
    75
    On the rEvo a CMF limits the unit to 80m, so I assumed thats why Jablonki and Lungren say "no ones doing meaningful exploration with a CMF."

    What's the depth rating of a Triton? Would you use a BOB for dives shallower than 80m?

    I guess if you don't have a solenoid you have to constantly fly both breathers manually, on ascents and it can be alot of work, when tasked.... I dunno I'm a newb .... but happy to be educated. @grantctobin
     
  3. grantctobin

    grantctobin ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: Chicago
    993
    691
    Shh nobody tell the KUR guys with a plugged IP Fathom. Technically with the needle, it's a variable CMF. With correct springs, higher test hoses, and a little luck on abysmal Apeks seat quality, you can get towards a 20bar IP.
     
    kensuf likes this.
  4. rjack321

    rjack321 ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
    Location: Port Orchard, Washington State
    11,181
    5,922
    Yeah ummm this is waayyyy out of date.

    Many people are either running way smaller orifices than the 0.035" in the Revo with a blocked 1st stage at a much higher IP. Or they use a high IP blocked 1st with a needle valve. Or they use an unblocked 1st and a needle valve. Getting below 80m on mCCR is easy peasy. Personally I have a 200psi blocked 1st.

    The days of CMF being an engineered depth limit are long gone.
     
  5. tbone1004

    tbone1004 Technical Instructor ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Greenville, South Carolina, United States
    18,457
    10,825
    make sure to check out Divesofts series on bailout breathers. The video linked before is the first of the series.
    They identify essentially 3 types of "non-primary" rebreathers.
    Bailout-if primary fails, switch to secondary
    Redundant-alternate between primary and secondary. Similar concept to sidemount diving where you switch every 10-20 minutes or so. Typically used on dives where the bottom time exceeds the scrubber time of the primary rebreather, but also as a way to avoid carrying OC bailout
    Deco-leave in habitat or "park it" to use on deco. Primarily on the dives where total run time is touching the capacity of the primary rebreather *6+ hour cave dives*.

    They have big names in the field who are diving these configurations talking about what paradigm they use and why which makes it quite interesting.

     
    Thrutch likes this.
  6. broncobowsher

    broncobowsher Solo Diver

    1,977
    1,456
    Somewhere down this rabbit hole you will be wondering if you should have made that left turn in Albuquerque.

    I think we answered the OP question if it really does exist.
     
    cathal likes this.
  7. Thrutch

    Thrutch Solo Diver

    # of Dives: 200 - 499
    Location: Reno, NV
    32
    55
    I got more answers than I bargained for. So much to learn!
     
  8. marsh9077

    marsh9077 Contributor

    # of Dives: I just don't log dives
    Location: Australia
    344
    289
    As Rjack321 has mentioned this is a pretty old school train of thought, I am not saying its wrong as some may still go by this however I don't believe this. But as I have said be for there are many different factors that play into the style, thoughts, mentors of other, regions you learn in, etc. on sub 100m diving etc. as its not something that is commonly done, your talking about maybe 1% of the diving community.

    I think out of the box the Triton is CE rated to 100m but that is beside the point, not realy trying to get info a debate about what unit is the best for BOB this is all personal opinion and based on what type of diving your doing and the application. Every unit has its strengths and weaknesses. I would not consider using a BOB for an 80m. For me I think the 150m rage is about where you start to consider a BOB or when your TTS exceeds your scrubber time this is where I mentioned earlier it makes a great deco unit. There are lots of different applications for secondary units so it really depends of what your trying to do with it.

    For me primary unit is an eCCR secondary would be a mCCR so primary I just set my SP and monitor no manual flying required and secondary I just make sure loop has the dil I'm diving for that depth and flush through accordingly as I dil switch. If you need to switch to secondary unit then primary unit is switched to low SP and you just forget it. Secondary unit you just monitor and adjust SP accordingly like you would just dive it normally like any other unit there is no extra work expect that you have to occasionally dump some gas from your primary CL on accent. But this is just one train of thought on how to dive two units, there are many others and a lot depends on the application.
     
    Heat Miser likes this.
  9. Heat Miser

    Heat Miser DIR Practitioner

    # of Dives: 200 - 499
    Location: Perth
    117
    75
    No probs, I'm not trying to debate, I'm just really trying to understand. As you say BOB's are for a pretty limited special application purpose. The Triton looks fantastic because of the size and chest mounting and I have heard of people talking about taking them to 200m, I'm just wondering how they a modified for bail out purposes.

    So when people on this forum are talking about plugged 1ast stages or CMF with needle valves are they talking about units with the CMF 'effectively' turned off? Or is there a nuance I am missing, that the CMF would get switched on or off during the dive?

    Here's a write up from Richard Harris (the twin megladon famed guy in Video above) talking about one of his team laying line to 175m, using a rEvo/Triton combo.

    http://www.wetmules.com/projects/thailand-cave-diving/REVO-TRITON.jpg?attredirects=0

    OR

    Thailand Cave Diving - The Wetmules
     
  10. rsingler

    rsingler Scuba Instructor, Tinkerer in Brass Staff Member ScubaBoard Sponsor

    # of Dives: 500 - 999
    Location: Napa, California
    5,621
    7,155
    Here goes another thread derailment, but...
    I hear this again and again: Apeks seat failure in a high O2 environment...
    Is there a thread? Should I start one? Where is the data?
    And if it's true, why hasn't everybody switched to Poseidon XStreams? Or at least 3960's?
     
    Geo7 and cathal like this.

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