Rebreather with a long hose

[Kevrumbo]

offboard o2 is ridiculous (you don't need 40cf, you need maybe 4 to 6cf)
And creates a whole bunch of new ways for nasty water to get into your solenoid or orifice.

The GUE JJ uses onboard O2 fyi

And it's placed in a horrible spot.

They get used to it. . .

 

[Michael Guerrero]

offboard o2 is ridiculous (you don't need 40cf, you need maybe 4 to 6cf)
And creates a whole bunch of new ways for nasty water to get into your solenoid or orifice.

The GUE JJ uses onboard O2 fyi

Water intrusion into an orafice might be a concern, but people don't seem to have a problem with the unit I'm looking at. No solenoid on it though.

Are you saying that if I bailout at the end of a dive from a couple/few hundred feet and have to deco on OC then there is no way I would need 40 cuft of O2 for my deco time?

 

[kensuf]

offboard o2 is ridiculous (you don't need 40cf, you need maybe 4 to 6cf)
And creates a whole bunch of new ways for nasty water to get into your solenoid or orifice.

The GUE JJ uses onboard O2 fyi

You should have the option to switch O2 to an off-board feed. IMHO, the feed should not be compatible with your DIL feed. I use a QC6 for DIL and standard schrader (inflator) for O2.

A friend of mine had a seat failure on his O2 when he was 3500' back in a cave at 330' of depth. He was staring at 6 hours of deco too. I bet he was glad he could plumb a second O2 source into his rig. I make it part of my regular SOP to carry a spare O2 on "bigger" dives.

 

[rjack321]

And it's placed in a horrible spot.

seems hard to reach
Personally I don't like the backmounted dil/BO because

I'm essentially setup like the KUR guys although I don't know their long hose stowage places/procedures.

Water intrusion into an orafice might be a concern, but people don't seem to have a problem with the unit I'm looking at. No solenoid on it though.

Are you saying that if I bailout at the end of a dive from a couple/few hundred feet and have to deco on OC then there is no way I would need 40 cuft of O2 for my deco time?

I'm not going to belabor the UTD version of the Kiss. No solenoid, no orifice and running the unit manually 100% of the time is just dumb. I don't think anyone has died on one yet but their market penetration is tiny anyway. People die from hypoxia - more often than they should. Relying on manual operation dive after dive is playing with fire when you get distracted by fishing line, or scootering or running line or a big whale you swim after and ascend at the same time. To each is own but that "design" was done by someone who never dove a CCR before.

On most ocean dives to 180-200ft ish every CCR diver I know brings an 80 of bottom gas and an 80 of deco gas, 50% and 70% are probably the most common choices I see. Its a long way up to 20ft and so O2 is a poor first deco gas choice unless you are already shallow. Its pretty hard to rack up much deco on a recreational depth CCR dive in the ocean (for me) I either run out of dive site to see or my buddies get cold or the current changes or we multilevel up or whatever but on a 90ft dive I basically never have ocean deco.

I only add O2 for deco below about 180-190ft so I think carrying 40cf of the wrong gas is a waste of space and a whole bunch of drag for nothing.

 

[rjack321]

You should have the option to switch O2 to an off-board feed. IMHO, the feed should not be compatible with your DIL feed. I use a QC6 for DIL and standard schrader (inflator) for O2.

A friend of mine had a seat failure on his O2 when he was 3500' back in a cave at 330' of depth. He was staring at 6 hours of deco too. I bet he was glad he could plumb a second O2 source into his rig. I make it part of my regular SOP to carry a spare O2 on "bigger" dives.

I have a BC whip on all my deco gases for exactly this reason. But that's different than hauling around an al40 of O2 (into the cave too) because you only offboard your O2.

I use a QC6 for dil and BOV too

 

[PfcAJ]

seems hard to reach

It also doesn't scale. It only works with those baby lp50 tanks. If you need more bailout (85s, 120s) it goes from difficult to reach to impossible.

 

[rjack321]

It also doesn't scale. It only works with those baby lp50 tanks. If you need more bailout (85s, 120s) it goes from difficult to reach to impossible.

My buddy diving this unit/setup just adds stages. No bigger backmount bottles.

 

[PfcAJ]

My buddy diving this unit/setup just adds stages. No bigger backmount bottles.

Less than ideal. Adding in gas switches and more equipment because your configuration can't support larger tanks only serves to complicate your response in a true emergency.

 

[rjack321]

Less than ideal. Adding in gas switches and more equipment because your configuration can't support larger tanks only serves to complicate your response in a true emergency.

Agree but for different reasons. Backmounting tanks is ghastly heavy and for the BC caves I dive running OOA (or BO) isn't the issue. Breaking your ankle is a significantly more prominent risk!! I had a friend break his leg walking on wet grass in doubles (compound tib-fib fracture) here is the city with an ambulance 5 mins away. Doing that in the bush is life threatening.

Hence the SM. I max out with 2x sidemounted 130s. While in theory I could add a stage bottle to 130s, in practice its beyond me right now. I can add a stage to sidemounted 85s as they are smaller diameter and easier to work around. So net I end up with a few options:
SM 80s = 150cf (for peacock or something like that)
SM 85s = 200cf (most dives)
SM 85s plus a stage = 280cf
SM 95s = 240cf
SM 130s = 260cf

Open water is different, I have yet to need more than 80cf of my deepest gas.

 

[Kevrumbo]

Less than ideal. Adding in gas switches and more equipment because your configuration can't support larger tanks only serves to complicate your response in a true emergency.

Well, this petite JJ CCR GUE Diver here in LA can very well manage a 70ft/21m MOD back-up Open Circuit deco 11L cylinder: