Something similar, but not all the way down to one-half air pressure. A good friend on my survey team had a sudden and significant oring leak develop at a DIN connection about 1200' penetration into Phantom Cave in west Texas. Max depth had been 68', with the average about 30. I was still outside the cave and I don't know their depth at the time leak developed. It was the oring at the DIN reg to valve connection on one side of her isolation manifold. She started with 3000-3100 psi, but I don't know the remaining pressure at the time of incidence. (probably around 2500) They had been moving slowly taking compass shots and line measurements, so had been in a while longer than would have been necessary to normally get to that point. She was able to shut down the valve in textbook fashion. Her husband was close by all the time to assist if necessary, and they made a safe and easy return to the cave exit.
I was suggesting a long (5' or 7') LP hose for the SH reg on the right post of the manifold (as per "normal" tech setup). You seem to be talking about lengthening the corrugated hose on the right horn of your DH reg by a couple inches to account for the 7 inch offset of the cans to the left. I would think this would be unnecessary, as standard length loop hoses should still reach your mouth easily. Maybe not; I guess I'll find out when I try it. If anything, you could maybe shorten the left side of the loop a little or add a weight to keep it from floating up higher than desired (though this may also not be necessary). I'm going to start by trying it with the standard loop hoses it came with, both for simplicity and ease of switching back and forth between singe and doubles diving without having to change out the loop hoses. We'll see how that goes.tripplec wrote: ↑Fri Dec 28, 2018 4:35 pmThey used to make longer hoses for a DA if I remember right. I have been thinking your same thought. I think I may have even seen a picture somewhere of someone who pieced two hoses together for the outer most hose and used a long hose for the inside. A picture from the black and white days. I imagine the hoses would have to float the same height to keep breathing normal.
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No trouble turning my head to either side. No different than with 2 single hoses on doubles or a double hose on a single tank.
Yeah, the point was just to give an example of how the simplest solution for diving a double hose with double tanks may be to just take your regular doubles and swap out one of your single hose regs for the double hose reg you would like to breathe from. The test was "does it breathe OK if the DH is on the left or right, rather than right in the center" and my answer to that was "yes, it does."Ron wrote: ↑Wed Apr 17, 2019 6:39 pmSo let me preface this by saying that I firmly believe in "to each his own." However you want to dive is fine with me. I'm talking about this for the sake of the technical discussion, and not to be for or against your personal preferences.
This just seems like a sub-optimal use for isolated doubles. In this case, I'd just use 2 single hose regulators with DIN fittings. I just cannot see why this configuration is better than a 7 foot primary and a 22" bungeed backup.
I say that as a dude with 9 double hoses in my dive locker.
For me, I'd rather dive double 72's single outlet with a double hose, a buddy, and a hang bottle. That's how I do my vintage style deco dives. Now I don't do 200 foot dives that way on trimix, but I do 150 or so foot dives with small decos with a trusted buddy, a double hose, single outlet double 72's, and a bottle hanging at 15 feet. You can share air if you need to until your 15 foot stop, then hang on the bottle.
Would I do our local 210 foot deep wreck that way? No. I do that in double 100s with a isolator manifold, 2 single hoses, and a slung 50/50 aluminum 80 as a deco cylinder.
I just don't see what problem doing this actually solves. It's more complicated than isolated doubles with 2 single hoses. It's more convoluted. It's less easy to share air. It's less easy to route a 7 foot hose. It just seems like something to do...just to do. Again, to each his own. I just don't see how this is a better use case or more optimal configuration that what the rest of the tech diving world already does. I reserve the right to be swayed from my present opinion.
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