I’m interested in sidemount diving but before I invest in the equipment, I have some questions:
- all the movies are made in nice hot water but I dive in cold water with a drysuit and a Weezle undersuit: how does the system work in cold water? What with the lead, do you need more lead?
- the Z-system is for 1 stagebottle. Is it possible to put a second stagebottle on the harness in the future?
- most of my dives would be as sidemounting but rarely I still want to dive as backmounting. Is it possible to install a divebottle on the back?
If I read your explanation, if I buy a UTD Z-Plus - Single System Complete (Rec. Side-Mount Version), then I have everything to dive sidemount and backmount. Another question: can I put an OMS backplate on it for backmount diving?
As a side note: Divers have expressed concern that the Z-System has a single point of failure in the Z-manifold. This is true, but that is a risk that has an equivalent in back mount and that we have a protocol to handle. Let's discuss this point. We do have the same single point of failure when you dive a std UTD/DIR double tank system. That is the isolator knob. If we somehow damage the manifold isolator knob, we will be unable to shut down the knob and loose all the gas. Remember, it is high pressure, if you smack it and destroy it, it will be a catastrophic lose of gas. Secondly your "only" bailout is your teammate. With the Z-System, if you were able to damage the Z-manifold (much lower profile than the Isolator Knob on a set of doubles), it is low pressure, far less catastrophic than a high pressure failure, secondly your bailout is "Traditional Side Mount". Meaning that simply unplug the QC6's, and you now have independent double side mount tanks with a second stage attached to either the first stages of the cylinder. You can also have a second stage with QC6 female in your pocket and simply plug the QC6'ed onto each of the stages as needed. Keeping in mind a third option is your buddy (std UTD/DIR option.) SO in actually fact you have two (2) bailout options in Z-System whereas in UTD/DIR std back-mount you only have one option.
While I appreciate your point of view, a single point of failure exists in all systems, from backmount DIR to rebreathers to Side-Mount. For example in backmount DIR (Double Tanks with Isolator Manifold) if you were to slam into the ceiling and shear the isolator knob off (High profile, high pressure, dynamic o-rings) on a set of doubles (That is a more reasonable scenario than breaking the z-manifold), you would first and foremost lose all you gas and all your diving functionality including breathing gas, bcd gas and drysuit inflation. Your bailout would be solely be your buddy.
In the Z-Side-mount system, we use the z-distribution block to "enhance" the functionality of the system and DO NOT RELY on for the dive. By distributing the gas, one is able to enjoy all the benefits (Long hose, necklace, bcd and so on at all times) with far less risk than an isolator knob on a set of doubles (z-manifold is low profile, low pressure, static o-rings). If you have any issues such as you suggest, your first line of defense is bailout to side-mount and then ultimately your buddy. By bailing out to traditional side-mount you can simply unplug the cylinders and use a standard second stage to breath the gas, you can orally inflate the BCD. and obviously you are bailing out so you are heading home so drysuit inflation is unnecessary. I know..... I know, you gonna say but in a cave we may have to...........My answer would be "Like in any special circumstance, if you have to descend on the way home, you can put an extra LP hose on a cylinder, or wear a separate drysuit inflation bottle like we already do for technical and trimix." Point is, I could make a thousand and one arguments as to why the "typical" side-mount configuration will fail in a circumstance, if you lost this hose then this or that hose then that. Here is the crux of the matter. With the Z-Side-Mount System and the Z-Manifold Block (Distribution block) what I get is all the benefits (listed below) without increasing risk, in fact less than an isolator knob on a standard set of doubles manifold which I dove successfully for 20 years anyways. IMHO
Benefits of Z-Side-Mount System over Traditional Side-Mount
Scalable - I use ONE system for all my diving... Single (1) Tank (Recreational), 2 tanks (Tech-reational), 3 tanks, 4 tanks. Deco bottles, Stages.... even my Rebreather (PSCR and mCCR) - One CANNOT do it this with traditional Side-mount. Imagine that you can now stage a cave with cylinders, and deco bottle, plug them into the system and always have donate-able long hose, necklace, bcd, drysuit and even rebreather function with any cylinder in the cave
Consistent - Within a UTD/DIR Team and all environments. Can easily dive wihin a mixed team (back-mount, rebreather and side-mount) and still have the donate-able long hose wrapped around your neck (NO MORE Stuffing the long hose) Best of all you can ALWAYS DONATE FROM MY MOUTH - again something traditional Side-mount configuration does not offer. With Z-System we can even do better than with traditional UTD/DIR back-mount in that we even have donate-able long hose during DECO :)
Minimalist - Only take what we need. We don't need to configure every tank and/or stage bottle with two regualtors, drysuit hose and BCD hose. Again when staging a cave ( dropping stage and deco bottles) to do big pushes, we do not worry about the fact that the stage bottle only has a single regulator on it (traditional BAck-Mount and side-mount) When we use to dive stages, we would use them first and drop them at 1500+200. Scary thing was when you came back to it, it only had a single regulator on it, NOW we has this ability plus we can pug it into the system and get FULL Functionality.
Integration - It integrates perfectly into our already established 20 years of UTD/DIR/Hogarthian system. The light is still on the right side, the argon is still worn on the left, the 7'/2m long hose still wraps around your neck and tucks under the light or knife, you are always breathing a donate-able hose, you still have a necklace regulator always ready to go, you still rock bottom gas management, you still use Ratio Deco... blah blah blah. Essentials it fully meets the 10 covenants of UTD.
This of course is a short list, but gives you the basic idea. Let me know if you have any questions.