First Rebreather Purchase - Lots of Questions

[AJ]

I'am looking into rebreathers also. Read a lot of theory about them and searched the internet for info. One thing to consider in my opinion is: how much help do you expect form your breather? It seems to me every rebreather type/manufacturer has it's own philosophy about the amount of help a breather should provide to the diver. Some breathers try to prevent bad things happening by adding extra electronic safety measures. This unfortunately makes the breather more complex.

For myself, I like a simple machine that I understand and can control. I absolutely hate a computer or machine thinking for me. Therefore I like the concept of the JJ. It's based on the KISS principle, but I yet have to try one so I may be wrong? Please chime in experienced breather pilots!

 

[taimen]

JJ is great and I love mine. I could still recommend another unit if you happen to have easier access to training and buddies diving it. And factor in the cost of training (including travel) up to MOD2 level if doing price comparisons.

 

[taimen]

For myself, I like a simple machine that I understand and can control. I absolutely hate a computer or machine thinking for me. Therefore I like the concept of the JJ. It's based on the KISS principle, but I yet have to try one so I may be wrong? Please chime in experienced breather pilots!

First of all, I am not an experienced diver but I comment on this because I have recently gone through all these questions. Opinions on electronis will be divided. Usually people who favor manual control are slightly louder. There are many issues in rb diving where (reliable) automation should add considerable safety (because many failure modes lead to progressive incapacitation and thus weaken your chances to stay in full control). Unfortunately implementations of these automatic safety features in rebreathers have been unreliable this far. Compare to cars, electronic stability control and anti locking brakes do prevent accidents but it took decades and millions of cars for the technology to mature.
With a JJ you have a primarily computer controlled eccr rebreather. It is just as simple or complex as any other Shearwater eccr with one solenoid. There are units with less computer involvement if that is most important for you. Personally, I don't care that much. It is not "trying to kill you" and it is not trying to think for you. It only tries to obey a simple set of rules but you must monitor it continuously as it is unable to detect or solve any problems.

 

[AJ]

Personally, I don't care that much. It is not "trying to kill you" and it is not trying to think for you. It only tries to obey a simple set of rules but you must monitor it continuously as it is unable to detect or solve any problems.

Ghe, ghe, I heard the statement "trying to kill you" lots of times. I don't believe this. Instead I believe the machine is trying to keep me safe, even with electronics. I trust electronics, I just do not want to blindly rely on them as some divers like to do, so I'am totally with you That's why the JJ appeals to me, but I could be wrong. Don't know yet.

 

[michael-fisch]

I've got a SF2 fitted out for cold water drysuit diving, with 2x3L tanks, 23Ah Battery tank, wing, backplate and the necessary 2lb P-Weight it weighs 43Kg ready to dive and has the most uncomfortable WOB of all my breathers.

My XCCR is fitted out the same way, with 2x3L tanks, 23Ah Battery tank, wing, aluminum backplate without P-Weight weighs 53Kg ready to dive. Even though it weiighs 10Kg more than my SF2, because of the superior WOB this is the breather I use most.

My next RB is going to be a JJ with 2x3L Tanks and I hope that I'll save about 5Kg compared to the SF2, with the same ease of breathing offered by the XCCR.

Instead of Bailout bottles on longer dives, I've gone to a FLEX, rigged as a selfcontained Bail Out Breather with 2x1,5L 300 Bar composite tanks, a 2 button MAV, with Shearwatwer Petrel II to let me know whats happening. Neutrally bouyant it weighs 22.8Kg, and is easy to breath.

Michael

 

[kensuf]

Apologies - the comment maybe could have used a bit of clarity and I think I may have ruffled a few feathers with no interest in the tech diving. It was more along the lines of carrying the 100+ pounds of gear etc on OC here in the PNW so a sidemount is probably not my preferred path.

I work in a highly technical scientific field so attention to detail is literally what I do on a daily basis - my ability to handle the CCR is definitely within my wheelhouse.

This was simply just a very general ask.

Even with a CCR you're going to be carrying a bit of gear. You'll need adequate bailout for the dive you're planning, no matter what the dive is. Plus a fully loaded CCR will be around 50#.

Might I dare suggest trying a set of double aluminum 80s? They're not that heavy, will give you twice the volume of gas to what you're currently getting, and relatively stable. Plus it'll be about $9000 less than a CCR with the appropriate training. Maybe $8200 less if you also sign up for a Fundamentals / Intro to Tech class as part of the deal. That's a lot of fills...

 

[doctormike]

Another vote for the JJ. Of course, I'm only certified on that one, and maybe I'm biased, but I did spend a long time looking at the various options.

The JJ is a marvel of engineering. Everything is VERY well thought out (happy to go into details if you want). Simple and robust. I really like the clean front with back mounted counterlungs and SPGs stowed in the back. No issues with WOB or position, in my experience. Great flood tolerance. Easy assembly, operation and cleaning (at least by CCR standards!). Built like a tank, and used by some very experienced divers. Great support both from the US distributor and from Jan in Denmark.

As far as the decision to jump to CCR, I understand what the OP is saying. I don't do dives where I need a CCR, where the OC gas requirements would be prohibitive. I do light deco, and I really like the longer bottom times in intermediate ranges. Plus the quiet for marine life photography (although I think that this feature is a bit overrated). But more than that, I just really love CCR diving. It has revitalized my interest in diving in general. I love reading about rebreathers, talking about them here, learning about them from more experienced divers. I even enjoy building it and cleaning it after the dive!

I'm a proponent of not buying a unit until you are certified in MOD 1. That's what I did. Yes, it costs a bit more since you need to rent a unit to train on, but until you are CCR certified, you just really can't understand the tradeoffs between the various rebreathers. I trained on a JJ, loved it, and bought one. But I can imagine buying a different unit than the one you got your first cert on, if you had problems that were unit-specific.

 

[rddvet]

Some units may travel slightly lighter, but none of them is small enough for flying without checking in some luggage.

I can get my entire Fathom setup into a carry on case including computers and wing. Only thing I don't put in the carryon is my backplate. I could make it happen, but then it would be very tight. For two divers in drysuits my wife and I can travel to Mexico with a carry on and personal bag each onto the plane and 1 checked for drysuits and other stuff like fins and mask

JJ is an awesome unit btw. One of the ones I was considering

 

[wedivebc]

One of the best travelling rebreathers is the ISC Pathfinder. It uses the same electronics as the Meg 15 (sadly discontinued). You can find used ones in the $5k range and since ISC is discontinuing the Pathfinder they may have a deal going since they only have a few units left. They have comitted to supporting the unit for quite a few years to come.
For deeper than 200ft you will want a Tiburon meg with mini (5lb radial scrubber) or cave can (8lb radial). All of these rebreathers will fit in carry on luggage.

 

[tbone1004]

@wedivebc I'm not entirely sure that it is "sad" that the Apecs electronics have been discontinued given that the Tiburon has come out with industry standard electronics these days....
Not having stood them next to each other, is the Pathfinder that much smaller than the mini Meg?