Playing with the UTD Z-system

[Jax]

Its a byproduct of pisspoor design in an unnecessary piece of the product being sold(ie, a crappy 'manifold' that solves no problems, but manages to increase hassle).

Ah, now bugger, you can do better than that! :blinking:

 

[Rainer]

The setup is a nice way to allow monkey diving and enable the divers to share gas, without any convoluted hose setups.

I occasionally monkey dive. I was never a fan of either having only one second stage (i.e. forcing buddy breathing or CESA) or stowing a spare under stage bands (takes time to access in an emergency).

What we've been doing here is taking a standard stage reg (1st, 2nd, 40" LP hose, plus SPG) and simply adding a second 2nd stage on a slightly shorter hose (~32") and bungeeing that one under our chins. This immediately gives you a spare second stage, the ability to donate from the mouth and go to a bungeed backup (typical DIR/OC tech donation), and is relatively inexpensive (I picked up a brand new Hog 2nd for about $70 and had a 32" hose sitting around already). Sure, a 40" hose isn't the same as a 5-7' hose, but it's no different that what you'd donate from a stage/deco bottle, and used to be one of the standard recreational OW DIR hose lengths. For ~30' max OW (non-overhead) dives, it's just fine. When you aren't monkey diving, just remove the extra 2nd stage and add back the port plug.

Personally, I see what we've adopted as a much simpler/cleaner solution to monkey diving than "monkeying" around with (expensive) QC connectors and manifold blocks.

I don't SM, so have no opinion on how the Z-system would fare for that type of diving (though as you note, it does seem to miss the redundancy benefits of either a traditional manifold or independent twins).

 

[SuPrBuGmAn]

What we've been doing here is taking a standard stage reg (1st, 2nd, 40" LP hose, plus SPG) and simply adding a second 2nd stage on a slightly shorter hose (~32") and bungeeing that one under our chins. This immediately gives you a spare second stage, the ability to donate from the mouth and go to a bungeed backup (typical DIR/OC tech donation), and is relatively inexpensive (I picked up a brand new Hog 2nd for about $70 and had a 32" hose sitting around already). Sure, a 40" hose isn't the same as a 5-7' hose, but it's no different that what you'd donate from a stage/deco bottle, and used to be one of the standard recreational OW DIR hose lengths. For ~30' max OW (non-overhead) dives, it's just fine. When you aren't monkey diving, just remove the extra 2nd stage and add back the port plug.

I use a 32" hose for one of my tanks SM'ing, or on an additional 2nd stage while monkey diving. It works perfectly fine. The 32" of line gives enough room should an OOA diver need it without me knowing(he has to get that close to get to it), and an easy swap to the long hose for exit/ascent. If I know a diver is OOA, the long hose is being donated anyway.

No Q/Ds, no shutting tanks down, no extra hoses routed around my back with a manifold thats completely unable to be shut down(to fix a nonexistant problem), simply no bull****.

 

[mikemill]

I missed something--what's the IP problem?

The manifold block is being fed from the 1st stage's low pressure port. So if you have two 1st stages with different intermediate pressure (IP) the tank attached to the 1st stage with the higher IP will drain and the other one won't.

 

[Dive-aholic]

It was just a tendency to roll to the left . . . and I'd stabilize out about 45 degrees left-side down. I talked to Jeff about it, and he said I needed to have my fins farther apart, and fin gently to resist the roll.

Completely unnecessary! Actually, you want your fins closer together. You shouldn't need to fin to resist a roll. My guess is either the cylinders you had on had different buoyancy characteristics (maybe a Luxfer and a Catalina?) or the rigging wasn't set up correctly. Finning may "fix" the problem, but it doesn't address the root cause.

Oh, and I'm going to guess it was more the rigging than anything else. Here's a video of my first monkey dive. At 5:07, you'll see me hanging motionless, no finning at all, and no rolling...

 

[ucfdiver]

Sheesh, UTD makes me lulz every time I turn on the internet.

In other news, they've released ANOTHER rebreather!

 

[LiteHedded]

Completely unnecessary! Actually, you want your fins closer together. You shouldn't need to fin to resist a roll. My guess is either the cylinders you had on had different buoyancy characteristics (maybe a Luxfer and a Catalina?) or the rigging wasn't set up correctly. Finning may "fix" the problem, but it doesn't address the root cause.

Oh, and I'm going to guess it was more the rigging than anything else. Here's a video of my first monkey dive. At 5:07, you'll see me hanging motionless, no finning at all, and no rolling...

yours looks like it's on the empty side while one of hers looks full and the other empty. that's probably where it's coming from

 

[TSandM]

Well, Rob, what I actually see is you a bit left-side down, and finning periodically . . . I'm not talking about being any more off-balance than that. I just don't like being off-balance, period.

I did do a "monkey dive" last fall in Hood Canal, where I carried a single Al80 with a backplate and no wing, and I did not feel as unbalanced -- but I wouldn't be surprised if I had moved some gas into my left arm and leg. You CAN'T hang weight off one side and not be unbalanced . . . but you can offset small amounts of unbalanced weight very easily with gas. The UTD wing is so small, and so confined, that you can't shift gas to one side of it or the other. The flip side is that, because of that design, it vents effortlessly.

I thought a long time before posting this, because I did not want the thread to turn into a UTD-bashing exercise. I am very grateful to Jeff for making this equipment available for us to beta test. I think the harness and wing have promise. I don't think the setup is unduly complicated for monkey diving, although it may be prohibitively expensive. I was very curious about its application for cave diving, and I am again grateful to have been given an opportunity to play with it, and make my own decisions about its usefulness. I am also very happy that here are folks thinking outside the box . . . most currently available sidemount setups are adaptations from backmount or open water rigs. These guys are at least trying to come up with something that's really built from the ground up for sidemount. There are limits to what they have done, and they need to know what they are, and go back and redesign. But I think there is no need to be snide about it.

 

[Dive-aholic]

I didn't mean to come across snide. I just don't think finning is the answer. I don't see myself left side down in the video and certainly didn't feel it during that dive. And there was no compensating for anything with gas. I didn't have a wing and that's a wet suit I'm wearing. The occasional finning you see was to control my buoyancy when my lungs weren't quite enough to do the trick.

I'm glad there are companies out there thinking outside the box, too. I believe the z-system has its uses, just like the Razor. There's no one sidemount system out there that will fulfill every the needs of every single diver. There's no "one size fits all", contrary to what some manufacturers believe (not referring to UTD here). As you've seen, I don't think any of the commercially available systems fit perfectly for my diving. I have ideas on what I would like. I just don't have the time or resources to put it together. I'd rather be diving.

 

[Tegg]

Just wondering... did you attempt to dive the rig without inflating the wing for any period of time?