introduction and seeking advice

Gill Envy

Greetings! Hope giving a long initial introduction is OK.
I’m a “wannabe” breather here in seattle. I have been diving OC for 10 years with aprox 600, mostly cold water dives. Have developed this hankering for kayak diving the current swept passes and coast line of north America from Baja to the northern gulf islands in British Columbia.
Myself, my wife and a few friends are getting tired of hauling some 22 scuba tanks out to remote areas for 35 to 55 min dives. We feel pretty whipped after an extended jaunt from all the nitrogen and physical exertion and wondering if we are even tempting fate with a DCI hit or accumulating any undesirable sub-clinical effects decompression. It seems clear that we would benefit from what rebreathers have to offer in terms of lightening our load, extending our range both in bottom time and how far we can realistically kayak our gear, improve our energy level during and post dives, potentially reduce our risk of over exertion related DCI, help us stay warmer and moister and so on. SCCR’s don’t offer us enough of an advantage and it appears that CCR’s are reaching a more attractive threshold in economy of scale and technological reliability as of late to warrent serious consideration for the advanced recreational diver.
We are getting ever closer to taking the plunge in $ investment and the extensive training we will need to unlearn our OC habits and basically start over as CC divers. We are trying out the evolution/inspiration next Thursday and the megalodon, kiss classic and the new optima from dive rite the fallowing Saturday. Before we try them out, we are attempting to gather opinions on their pros and cons so that we can make a more use of the try outs.
We are leaning toward a brand new megaladon (greater flexibility with O2 and dilluent tank sizes since it has no back cover, and can go as carry on without tanks and it looks like it is really well made though not as sexy, oh and it should come with a decompression computer next spring I’m told) vs. getting a used inspiration and upgrading the electronics (larger gas capacity than the evolution, and overall a well oiled stream lined machine with an integrated decompression computer and long track record…used and upgraded would cost a little less than a new megaladon with all the bells and whistles).
We typically dive no-deco and we’d like to venture deeper with little to no deco as we don’t see ourselves becoming deep tec divers. We realize that with the requisite experience and training our comfort zone may expand, so we are thinking it would be best to puchase a unit that has a largish gas capacity, while on the other hand are a little leary of having a big gulky unit. And we are planning trips that would take us away from our vehicles for several days at a time, so having larger and fewer bottles seems logical. We are planning on taking 40 cft bail out. From the outside looking in, it is hard to get a real good idea of weather we should be going with a smaller unit and larger bail out or a larger unit to extend depth/time number of dives per set of chemistry and gas. We need help figuring out the pros and cons between these models and maybe others. Any comments and suggestions about models or general feed back about what to look for as we try out different models or more generally cautions and confirmation about how rebreathers apply to our application would be greatly appreciated. People with actual cross model experience would be especially helpful!
Gill Envy

CCR-Wrecker

I'm a little confused(a natural occurrence ) you speak of larger tanks as an option for the MEG, then say you plan on staying in the 130' range. I carry my bailout externally, as do most I'd guess. So I don't see that as a factor.
I myself dive a YBOD with a few mods. I am quite sure this would fit the type of diving you do, however.....if I was in the market for a new unit I'd probably look at the PRISM or the MEG. To each his own....

Ohh BTW- WELCOME !!

Andy

denzel

Welcome!

If you're looking at saving weight and want to pack as much as possible in a kayak, or keep the kayak as light as possible I'd look into the sportkiss.
Very different from a meg, but as simple as they come.
Don't get me wrong, I think the meg is a legendary unit, and my wet dream, but to say it's lightweight would be a lie...

denz.

__________________

Gill Envy

thanks for your reply andy. I modified my intro to clarify the depth thing. we'd like the flexibility to go deeper, we're just not sure what our goals will be until we see what we are really comfortable with. do you have a preference between the prism or the meg...if so, why?
I'm unfamiliar with the YBOB, does it have an integrated decompression computer? if not, do you use a deco computer?
thanks a gain,
george

CCR-Wrecker

Sorry George, YBOD=Yellow Box Of Death, aka Inspiration. I have a "classic" 2 handsets that double as fragile hammers , no deco computer is included. I cut tables using V-planner and run a VR3(tables are backups).
PRISM or MEG hmmmmmm YES!!! They both have strong points, oh and a back cover is actually a benefit IMHO, mine is scratched from bouncing off the Peanut tunnel. If you have the oportunity to try units, my advice would be: try as many as you can. Don't let people "turn you" based on brand names. Find one that fits and go slowwww.
My $.02
Good luck!
Andy

cajuncaver

Ok all... I am a Divemaster with 16 plus years diving. I'm working towards becoming a technical diver specifically going from Cavern to Full Cave. I have read multiple reviews/recommendations on several rebreathers; Expedition, Inspiration, O2tima. Can somebody point me in the direction of a document or a person who can tell me which one is the best to purchase and train on? I want to plan this purchase and get the device that will give me the longest and easiest use. HELP!

Thanks All,
Cajun Caver

__________________
To the Undiscovered Country...
Cajun Caver
New Orleans, LA

Gill Envy

hey there Cajun Caver, i've done a bit of talking around in the seattle diving community, particulary two long time divers i know from back when i was in the marker bouey dive club and sure enough, they both have switched from oc to rebreathers and both have chosen and rave about the megaladon for how reliable and bullet proof it is and how flexible it is in terms of using various sized tanks and such. I wish i could just give out their names but i don't have their permission. they are both tec divers, dive deep and i'm guessing their demands are more like yours than mine....for whatever that is worth. oh, and they both confer that getting a used inspiration with new vision electornics would be a great way to go too.
Gill

silent running

Hello Gillenvy, sounds like you've done some homework already. It is important to know and understand all the CCR designs you are considering. Understanding why each designer made the choices they did can take some time and will require a certain amount of reading btw the lines of manufacturer-speak.

It seems like you are pretty sure how you're going to use a CCR, and since you're going to do recreational profiles and don't have any tech ambitions, you'll probably want something simple and small-ish. This is where ironically, things get more complicated. The problem with smallest units is that they won't have much gas available for onboard bailout. You could wind up with a small CCR, that because of having to always carry extra offboard bailout, is not so small anymore. Most training agencies will require you to use offboard bailout, but for shallow NDL diving recreational diving to say 75ft, you would probably be OK with the onboard bailout capacity of the med. size units. IMHO, if you don't intend to carry offboard bailout, you shouldn't dive with less than 19 cuft dil cylinders and you would need to be able to top off the dil cylinders in btw dives. But this will not be possible unless there's a compressor onboard. So it could be that you will to have to carry offboard bailout anyway. Believe it or not, a good option could be a CCR converted Drager Dolphin/Atlantis. I have seen some nice passive addition, variable orafice conversions with very small O2 and Dil (8cuft I think) mounted on the side and the big stock Drager cylinder on the bottom as bailout. It was reasonably small, about as simple as it gets and should give you a whole day's diving without a refill.

I am not convinced of the need for integrated deco/computer in a CCR and they are all expensive, not to mention all the glitches I keep hearing about in the first generation units. I am not a fan of handsets with buttons, hoses and seals other than those in the head. There is definitely an argument to be made for keeping your dive computer and CCR separate as it's much less complicated and trouble shooting will also be simpler. If your unit keeps it set point properly, you don't really need to integrate a dive comp.

A big choice you will first have to make, is the one btw manual/passive addition or a electronically controlled sytem. Both have merits. I believe the Prism, which I dive, is a good meeting point of the 2 as well as being efficient and small. Take your time figuring things out and good luck-Andy

caveseeker7

Hi Gill, welcome to Rebreather World.
Just realized you made the same post in two locations, so I moved the single reply in the other thread over here and deleted the initial post. No sense having the same twice.

__________________
Cheers
Stefan



"It is still a good day if you are on the green side of the grass!

Su amigo Roberto!"

Sponsor Lou in Race For Life!

silent running

Hello again Gillenvy, I wrote my reply to your post before you edited it and included the additional info above, hence all the speculation about bailout. If you want to occaisionly go deeper or longer than recreational limits, the size of the onboard gas supply becomes less critical and more a matter of convenience. At this point the scrubber then becomes the limiting factor in dive planning.
As for cylinder capacity, on my Prism, a stock full 3000 psi 19cuft O2 cylinder will give me at least 10 hrs of diving. However, unless you have a booster pump, you might not be able to get a full O2 fill to 3000 as it is hard to find anyone who pumps it that high due to safety concerns. Anyway, your particular situation might necessitate a unit which can take bigger cylinders. Both the Meg and the Prism can be fitted with larger cylinders, the Prism up to 40cuft's, sans cowling. Or you could just get another spare pair of the smaller 19s and save yourself a back ache.
I still think the CCR converted Drager is a great simple recreational unit, as I mentioned above due to the small cyls for the O2 and dil, with the stock Drager cyl functioning as a good sized bailout. They can handle up to a 5 ltr. But I also think the Prism is a good bet as in stock form it's got the best scrubber duration and except for the Sport Kiss, is the smallest and lightest. Mine is 47lbs ready to go. The Prism also has the lowest WOB and can be tricked out for tech stuff easily. I think it's also the safest because it can be flown with no battery power, due to the passive secondary gage. Take your time deciding and things will become clear-Andy