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UTD Z-side mount with isolatable manifold

Discussion in 'Sidemount Diving' started by eelnoraa, Jul 29, 2013.

  1. MScorpa

    MScorpa Solo Diver

    # of Dives: I'm a Fish!
    Location: Westminster, Maryland
    What a great thread! I love when experienced divers get to bickering as to why 'thier' way is the better way...seriously. It brings up a lot of very good points and insights that may not have occured to some people.

    Personally, I constructed a distribution manifold (like the old z-system) when I first started sidemounting. It actually did work extremely well! Just plug in the tanks and go. The newer isolation manifold resolves one of the key potential problems with my rig. It was nice to have everything in its place. I think it gave me a good sense of comfortability and familiarity while transitioning from backmount to sidemount.

    The reason I stopped using it is because it was a much heavier rig for traveling and took up more space with the additional hoses etc. I also prefer to dive as minimalistic as possible and lets face it, this just isn't the rig for a minimalist. I didn't like the fact that I had to turn the tanks off as I was breathing them down, I like my air on and available at all times. I also pondered if a panicking out-of-air diver did come to me I could just give him a tank and send him on his way, not possible with the z-system.

    As previously mentioned, it's training and comfortability in the water that is key in an emergency situation. My instructor used to say, "It doesn't matter what happens to you, because things will happen, it's how you deal with it." If you are diving with someone in a tight cave with zero vis and you run out of air, you'd better be familiar enough with your buddy's equipment beforehand to handle that situation. It shouldn't make a difference how he has his rig set up.
    tiki_bill likes this.
  2. TheRedDiver

    TheRedDiver DIR Practitioner

    The QC6s hoses can be assembled for much cheaper than what UTD is asking (male / female) (~120$ per hose side... so ~480$ for just the hoses).

    Get the SS-QC6-D-4PF and SS-QC6-B-4PF (SS = Stainless Steel, QC6 = Quick Connect 6, D = Double shutoff, 4PF = 1/4 NPT Female threads, B = Body) for ~20$ each and 1/4 NPT Male to 9/16 Scuba Male for ~15$ ... for a total of ~35$ per hose end. If you have some 22" hoses laying around like I did you can just connect those ends up and boom (~140$ for all QC6 ends, which is 340$ savings). If not, the hoses aren't too expensive (~15$ each, so 200$ total, which is still 280$ saved).

    You can, alternatively, get SS-QC6-D-4PM and SS-QC6-B-4PM (male threads) as well, but rather than the above mentioned adapter you will need 1/4 NPT Female to 3/8 Scuba Male (cheaper on amazon) & 3/8 Scuba Female to 9/16 Scuba Male adapters (I did this since it was cheaper, but more adapters, so some might not like it).

    I would avoid anything with a K# at the end... these are keyed and only work with others of the same K# (K4 works with K4, but not K2, etc)... from the picture it doesn't look like UTDs are keyed.

    The isolatable manifold (if you want it) is an irreplaceable cost (I looked into making something similar, but it was just a mess of too many connectors, ugly, etc). If you want just a distribution block (open water should be fine for this), you can get two Low Pressure Y Blocks - 3 ports and a 9/16 Male/Male Union (or any other combination [<- what I did] that accomplishes the same thing... free air movement between 6+ 3/8 scuba ports)

    You also need a OPV on your 1st stage, btw.

    Every thread in which the z-system is mentioned, regardless of if it is about the manifold or not, will degenerate into an argument over why the manifold is a good/bad idea... almost like a rule of the internet.

    I built a distribution block too! (see above)...

    The weight/bulk is definitely true... my cobbled together distribution block and hoses weigh a bit all together and are kinda bulky in the regulator bag (but both 1st stages, 2nd stages, block, etc all fit in my edge dive flag bag)... and re-attaching the block/hoses/regs to the rig when assembling for a dive takes time (guess I could leave it on, but then the harness is more bulky in the dive bag)

    If you have the 'spare reg' you could disconnect the tank from your QC6 and plug in the spare reg and give them the tank (they would have a 2nd stage on a 26" host basically)
    Last edited: Aug 22, 2013
    WhiteSands likes this.
  3. victorzamora

    victorzamora Solo Diver

    So, I know I'm kind of late to the party....but there's been one thought process not really touched in this thread: WHY sidemount doesn't need a manifold, and WHY backmount does.

    The reason for a backmounted isolation manifold is to prevent total gas loss from a tank. In the case of a leak, one can shut down the post and still access gas from both tanks. The time it takes to find the leak, figure out what's leaking, and then prevent the leak, still allows ample time for gas to be lost. The possibility of losing ALL gas is a risk mitigated by proper training.

    In SM, in the case of a leak, one can see the tank valves. One can easily shut down the valve to prevent further gas loss. There is NO possibility of total gas loss. The gas lost from a properly executed manifold procedure can be comparable to the gas lost over the rest of the dive by "feathering" the valve. This is an easy process, and I was taught to do it first (switch to reg from tank that needs feathering and bleed it dry, so in case things go wrong I have a "good" tank with as much gas as possible). The NEED for it is low. If you NEED the added complexity, cost, and failure points of the Z-manifold, then there is a training deficiency. This is the MOTHER of all "gear solution to a skills problem." In good conditions, I should be able to unclip or breakaway my long hose in VERY short order. In fact, in caves, I just drape my long hose over my shoulder and RARELY clip it off. If a buddy needs gas, I just throw the long hose at them.

    Also, you will RARELY have to donate gas in SM configuration if your buddies are in SM. If you're diving in a mixed team, and they go OOA without having foreseen it then they need better training and you shouldn't be diving with them. It's still easy to donate the long hose, but that should, IMHO, be your last dive with that buddy.

    ---------- Post added August 25th, 2013 at 07:51 AM ----------

    You MUST have a training deficiency if you think that in a zero viz drill, single file out through a restriction, that a buddy can "ZONK" your reg out of your mouth. I was taught my buddy is behind me pushing me out, in contact with the line and the buddy. Buddy up front has hand protecting head. Buddy behind has hand on front buddy's knee/thigh. Both other hands are on the line. If one buddy goes OOA, shake the contact point with other buddy and wait for donated longhose. In class, my instructor WATCHED me exhale fully, and then gave me the OOA signal (he touched my neck). Without cheating, my buddy was able to provide me with a long hose before I ran out of air. Heck, I didn't even get nervous/frustrated...I just waited.

    In the OW in good viz, a buddy "zonking" my reg out will be met with what I was taught in a cave. As soon as you see the diver go OOA, deploy the long hose with your right hand. Grab buddy's right arm with left hand and turn away from me while putting long hose in face. It only takes a second and is now a natural reaction. Buddy can't "zonk" anything, they get a good air source in their face, and everything works out. I've done both of the above drills, in a cave, over a dozen times. I know it doesn't sound like much, but they all went well and by the last 7 or 8 it was second nature.

    You're right, as long as something has a proper procedure we'll be fine. Let's reduce failure points and STILL have a proper procedure: I'll donate my long hose. If you're coming towards me and I don't have my long hose deployed and waiting for you, look at my right shoulder. If not there, jerk it out of my mouth.

    ---------- Post added August 25th, 2013 at 07:57 AM ----------

    I've never dove a scooter before, but I can imagine it well enough to know one thing: what you're proposing is crazy. You're stating that closing/opening one tank valve on your right and then opening/closing a tank valve on your left is easier than switching regs? If you put me on a scooter in OW RIGHT NOW I'd bet I could switch regs before you could get one valve closed. Also, if your hand is on the trigger then how do you shut the gas down on that side?

    PS- The note about "tell me more about SEA WWII wrecks" was sarcasm. You must've posted >1000 times with the dates, your He costs, and stories about it. I don't mind, I have just learned to mostly skip those posts.
  4. Kevrumbo

    Kevrumbo Banned

    # of Dives: 1,000 - 2,499
    Location: South Santa Monica Bay/Los Angeles California, USA
    (Reply to post #53 above):
    As for the process of switching tanks on Z-sidemount while on-the-fly-scootering (Right Tank currently open to start):
    --Turn on Left Tank valve with your left hand;
    --Take your left hand and replace your right hand that was operating the scooter trigger, continue trigger operation with left hand;
    --Turn off your Right Tank with your right hand.
    --Replace left hand trigger with your right hand as needed. . .

    Is that too hard (or crazy) for someone to imagine, even for a diver with no scootering experience at all?!

    Fundamental long hose DIR/Hogarthian technique has you ALWAYS breathing the long hose primary regulator on bottom mix, unless you've just donated to an out-of-gas buddy. In sidemount Z-system, the virtue of the distribution block [or the new isofold/manifold] is that you never have to switch out regs as you alternate breathing off of left & right tanks --i.e. alternating between shutting down one tank valve and opening the other in Z-system sidemount diving, you are always breathing the primary long hose regulator.

    Again, contingency training with the "added complexity" of the QC6 connectors [Z-distribution block or Z-isofold/manifold] is not hard to accommodate at all and can be learned like any new novel skill, technique & task. The fact I was able to utilize Z-system sidemount "right out-of-the-box", wreck diving in Truk & Palau, after only a few days orientation sessions before at UTD headquarters, is a testament to the ease of design, integration and implementation of this system: other than learning the new mechanics of QC6 connections and alternating independent tank switching & gas management, all my previous base knowledge, training and diving experience in long hose tech/deco/wreck overhead was perfectly consistent --quickly, seamlessly, and intuitively applied. . .

    Development & reasons for the Z-system from Andrew Georgitsis of UTD:
    Last edited: Aug 26, 2013
  5. victorzamora

    victorzamora Solo Diver

    I'm not saying that switching hands and turning valves is crazy in terms of difficulty. What I said was "what you're PROPOSING is crazy"

    Your proposition is that a juggling act between valves and scooter trigger and valves is harder than "Switch regs". Opening and closing valves is harder and more time intensive than switching regs WITHOUT the scooter. I can only imagine that adding the scooter adds complexity. And time.
  6. DevonDiver

    DevonDiver N/A

    # of Dives: 5,000 - ∞
    Location: Subic Bay, Philippines
    When the head of an agency, responsible for drafting policy and procedures, is also a major beneficiary in equipment sales, there's likely to be all sort of shenanigans and justifications. That's all I've gotta say...

    I wonder if UTD would have unilaterally adopted the 'z-manifold' as a ultimate solution, if it had come from OMS or DiveRite etc. Just saying....
    xdjio, tracydr and Doppler like this.
  7. Doppler

    Doppler Dive Equipment Manufacturer


    Having all that hardware behind your head is exactly what SM is intended to do away with. As for your concern about donating a hose in an OOA event, two things I would like you to think about.

    1) How often do you have to donate anything... for real: not during an S-Drill?
    2) Put a longhose on both tanks.

    For issues about swopping second stages during the dive, see my article in the latest edition of X-Ray Magazine.
    ianr33 and tracydr like this.
  8. eelnoraa

    eelnoraa DIR Practitioner

    # of Dives: 100 - 199
    Location: San Francisco Bay Area
    I think some of you missed the point of AG's intention as discussed earlier. His sole intention is to make side mount compatible to DIR and enabled mixed team. Now we can argue if that make sense at all. I don't know enough about side mount to say I agree or disagree. The z-manifold is just a piece of detail in the execution.

    I think the right discussion is NOT z-manifold vs traditional side mount. It should rather be the concept of tradition side mount vs mixed team side mount.

    ---------- Post added August 26th, 2013 at 10:59 AM ----------

    I like the idea in 2). But I respectfully disagree with the mindset in 1)

    Do you have a link to your article?
  9. victorzamora

    victorzamora Solo Diver

    eelnora, mixed teams aren't a problem from a sidemounter's perspective as long as there is a good dive briefing, your BM buddies are comfortable/aware of the situation, and you can either unclip your reg or "yank" on it. Switching regs is MUCH less time consuming, MUCH less of a hassle, and MUCH less dangerous than opening and closing valves. Also, would you rather have an inconvenience EVERY dive multiple times per dive that could cause you an OOA situation, or would you rather move to having the inconvenience of replacing a single ziptie in a true OOA scenario, and practically no inconvenience on a regular dive? To me, opening and closing valves is too big of a hassle to be compensated for by always breathing off of your long hose. Plus, switching regs allows you to maintain assurance that both regs are working. One of the big benefits of donating the longhose is you know it's working.

    My short hose is NOT to be removed. That is MY reg. That's what I was taught. I'll go out of my way to keep more air in YOUR tank, but that is MY reg. If I see somebody REMOTELY act like they've gone OOA, I get my longhose 2nd stage out in front of me and ready to donate. I've got weak zipties so that if you do go OOA, and nerves keeps me from unclipping the first time I can just yank my reg off of my chest and hand it to you. I've tried to unclip twice before jerking the reg off, deployed the longhose, and been prepared to control the situation in the time it took a buddy who was FACING me to swim 10ft and get the reg from me. Unclipping your longhose is a skill hogarthian BM divers practice, and it's no different for me.

    Most importantly, I don't see what the big deal is. I can dive mixed teams all day long. If I'm diving with a rebreather diver, I'll need to ask him before we dive to make sure it's cool (I can't imagine it's not)...but if I see ANY diver have an issue or an emergency I'm deploying my longhose and asking questions later. If you're a BM diver that won't accept my longhose because I don't have a manifold, then I'll keep the gas for myself and you won't have to worry about diving with me. I mean, if you go OOA I'll give you a longhose attached to a source of breathable gas. I don't see why you should care what else it's hooked up to. The dive's over, and proper planning means that we'll be just fine.

    Edit: I understood AG's point, I simply don't believe it to be necessary. Like above, a good pre-dive briefing, proper training, and a well thought-out equipment setup works much better than the convoluted hassle that the Z-manifold has turned out to be. It's solving a gear problem that isn't there, and it's solving a training problem with gear.
  10. Doppler

    Doppler Dive Equipment Manufacturer

    The mindset expressed in one is simply to question the status quo and to take nothing at face value. I know this upsets some but I believe it is the safest option. Please understand, I am not saying that we should ignore protocols that are there to help deal with OOA incidents, merely that we need to understand ALL aspects of risk management (including quantifying specific risks) so that we can put the appropriate resources aside to deal with them.

    Front Page | X-Ray Magazine

    However, the issue containing my sidemount article has not yet "gone to press"
    eelnoraa likes this.

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