+ Reply to Thread
Results 1 to 9 of 9

Thread: Obligatory 'Hi' and 'What should I buy' questions :)

  1. #1
    RBW Member sciron is an unknown quantity at this point sciron's Avatar
    Join Date
    May 2010
    Location
    Australia
    Posts
    2

    Obligatory 'Hi' and 'What should I buy' questions :)

    Fist and foremost hi to everyone, you certainly have a great resource here and you're certainly an active community all round (with varied opinions at times!)

    So with that quickly out of the way I suppose that i'm going to ask the 'what should I buy question' but not so much in terms of gear/brand (although i'm sure I will at the end of this post!), but more in terms of respectuflly asking if rebreathers are the right thing for me and my buddy?

    (i'll bore you all with the details now and appreciate honesty and candour in your responses.)

    My profile is that i'm 32, motorcycle riding for about 4 years (Honda Blackbird, 1100cc, beautiful) and (currently) relatively new Scuba diver (60 dives). I'm nitrox certified and about to do training on twins to get up with advanced enriched/deco diving.

    My best mate is also motorcycle rider (got me into it) and has knocked off a couple of hundred dives, also advanced enriched trained.

    What we both enjoy diving is wrecks and looking @ the southern cross divers site in Sydney (Southern Cross Divers Calendar) there appears to be a cavalcade of great wreck dive sites in the 45-75m space that would (I think) be ideally suited to rebreathers for extended bottom time while staying well on the conservative side of relative safety.

    ie A wreck dive with the possibility of 30-40m bottom time to explore would be amazing.

    Psychological profile of both of us is that (as an example) when we're out on the bikes, we both come home to a wife/gf so while we don't mind 'bending' the speed limit .... we're always riding 8/10ths (go hard, but still be conservative) and we both enjoying doing courses that continually push us to improve our craft, those that teach discipline and effective management of the infinite number of variables that exist when you're out there and mostly, how to make it home in one piece and not in the back of an ambulance.

    With that said, that 8/10th's attitude has helped us slowly progress into quite solid/fast riders and we can both easily handle ourselves with any of the 'fast' groups of riders that are out on any given Sunday.

    We are however always shaking our head at 'numpties' who are a casket/pine box addition waiting to happen.

    Not a club we want to be joining so we avoid the 'stupid' stuff.

    With all of that in mind, we have had numerous discussions around the lines of:

    1. We want to dive wrecks ... and a number of great wreck sites are in 55-70m of water + there's a plethora of great o/s wreck dives (Truk Lagoon etc) in that range.

    2. And diving OC on single tank to that depth is short and sweet at best and even on twins we're still getting (relatively) small bottom times.

    Which is how we got to talking about the proposition of rebreathers as a possible alternative.

    3. We're not the types of guys to be going to 100m or caves etc (though I respect those that want to), it's just not in our psychological profile to be wanting to go that hard, so while keeping it at 50-70m is still definitely risky, it leaves a lot more margin for error than is possible if you push yourself and your gear in situations where others may tread.

    (Much in the same way that while i've seen 250k's on the bike a few times, it's only after careful consideration of the risks, but then recognising that something can absolutely go wrong (think, kangaroo) and you have to live with the reality that you may not make it back and fatailty is a very quick step in those situations.)

    4. I've know i've said it above, but i'd like to say we're quite disciplined. When I first starting riding the bike my mate (Dan) and I would literally ride weekends, nights, inclement weather, etc etc (in every type of condition possible) to build that level of respect for all the elements that riding throws at you and to build as much awareness as possible on how to manage it when things (inevitably) go wrong.

    It was slow and boring, but built me into (I believe) an extremely capable rider.

    4. From the research we've done and speaking to a couple of dive shops here in Sydney that train on rebreathers, the feedback we're getting is that:

    a. It takes time, *lots* of time to get up to the skills on rebreathers, so as long as you're prepared to take it very slow and steady, you can have a great time with them and dive 'safely'.

    b. With that said, our number of dives at the moment (particularly for me) is not of deep concern as long as we're prepared to work at building skills, we are both disciplined and work together we've got (at least) 100 hours before we'd be doing dives of 50,60,70m

    So with all that in mind:

    1. Welcome your thoughts on 'is rebreathers the right technology' for doing the type of dives we want? Or should we just stick to twins/trimix (or some other combo?) as rebreathers are just not a good fit?

    2. Thoughts on diving Inspiration gear for this type of diving (both the shops we've spoken to train on them and seem to recommend them, I also understand they both have a number of people who dive them)?

    3. Anything else that you think is pertinent?

    Couple of other things before you all die of boredom.

    We're both financially in a position where we can 'afford' our toys, so we're not specifically thinking of this in terms of cost per dive or overtly concerned with reducing cost. (I know some people try to 'justify' the cost of diving rebreathers on costs, we simply wouldn't look at it that way, the sport is expensive and we're ok with that)

    With that said we just want to buy gear that we know as much as possible is reliable/high quality and with that the Inspirations seem to have sold the most number of units which is what is attracting us to them.

    And or course with two places local training on them i'm sure we can work on negotiating a good price for us :)

    If you've made it this far, my thanks to you, I (we) genuinely appreciate your honest and open feedback.

    Regards,
    Adam (and Dan)

  2. #2
    Enjoying the silence Lake_Tahoe_Diver will become famous soon enough Lake_Tahoe_Diver will become famous soon enough Lake_Tahoe_Diver will become famous soon enough Lake_Tahoe_Diver's Avatar
    Join Date
    Feb 2006
    Location
    Reno, Nv. (Lake Tahoe)
    Posts
    287
    Prism Topaz

    Kiss Sport

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    First, welcome to the group.
    There is no exact answer as to which rebreather is the best since each has it strong points. You can choose a ECCR or MCCR or some people like a hybrid that is both a ECCR and MCCR. There are many good rebreathers out there just need to figure out the one that matches your needs the best.

    Search the various reviews of the rebreathers and see which one meets your need then ask some questions.

  3. #3
    RBW Member Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1 has a reputation beyond repute Gobfish1's Avatar
    Join Date
    Apr 2005
    Location
    on the grassy knoll
    Posts
    1,454
    ybod

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    id stick with oc / till you hit 50m , twinsets and side slung is a nice work up to then going ccr, all tho you can still get 30mins bottom time at 70m on oc,, no need for ccr

    i used to get some good dives/ times with my twin 12s and a side slung 12l of bottom gas , in the 60m to 70m range.

    just my p2 worth ,, im sure others will say go and get a ccr now , and put some time in on it ,,

    no matter oc or ccr you will need to put some more dive time in
    ps welcome to rbw ,,
    Last edited by Gobfish1; 14th May 2010 at 01:13.

  4. #4
    RBW Member Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike has a reputation beyond repute Drmike's Avatar
    Join Date
    Feb 2005
    Location
    tokyo
    Posts
    4,504

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    on many dives the bottom time is dictated by how much deco you want to do (espeically on multi dive day trips) and on how much bail gas you can carry. More often that not unless splitting bail gas amongst team members and therefore team diving that means you will quite often end up doing the same BT on a set of twins as you would on an Rebreather. Of course there are exceptions but i regularly dive wrecks in that range with oc divers and buddies and often there isnt a huge disparity between what BTs we are doing (the main disparity is that they are doing the dive with less risk and a hell of a lot less buggering around) Like I said its often (but not always of course) how much deco one wants to do rather than gas availability that limits the BT

    Personally If I was in your position Id get some twins get a load of experience diving 50m wrecks on air - great training to become a solid diver. This is a good cheap and safe way to gain experience. [I am a firm believer in divers needing to learn how to deal with narcosis. learning to adapt response behavior and learn dealing mechanisms under narcosis i believe helps a heap when (not if) you have to deal with CO2 on a Rebreather.]

    Then do a mix course and do some mix dives 50-70m depth. Only after than would i suggest you go to Rebreather if you still want to.

    If you bail on a deep Rebreather dive you will find yourself suddenly and stressfully doing a deep trimix OC dive. If you havent got some deep trimix oc dive experience you are putting yourself at risk - IMHO right at the worst possible time. Some disagree - but mostly they have never had to bail deep.

    Of course there are many valid reasons to buy a Rebreather.

    One such reason is because one wants a new Toy - and thats a fair one

    My moto is 'he who dies with the most toys wins!'

    Im still collecting new toys, heres this months addition to my collection :)
    Attached Images
    Last edited by Drmike; 14th May 2010 at 03:54.

  5. #5
    Apprentice Meg Pilot kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu is just really nice kieranu's Avatar
    Join Date
    Sep 2005
    Location
    WA, Australia
    Posts
    708
    Megalodon APECS 2.7

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    I agree with what most of Mike said. Doing some 40m+ cavern or wreck dives in cold water on OC air will certainly help you adapt to dealing with issues while narced.

    If you are doing a fairly square profile and make appropriate gas choices with your buddies then bottom times and deco would probably end up fairly similar between twins and CCR though, unless you have to do a full bailout, gas usage will be considerably reduced so your gas costs will be reduced and can be more convenient when traveling (for instance I recently did a road trip with 4 3L cylinders, 1 5.7L cylinder, and a 11L cylinder containing all the gas that I needed for ten 60 minute dives and more). Most of my bailout cylinders are over a year out of test because they don't need to get topped up very often. So far I have been fortunate and haven't fully flooded my rebreather so I have never been required to do a full ascent from depth while bailing out so most of the off-board gas depletion comes from use in my dry suit, sanity breaths, or manual addition if I run out of onboard gas.

    Personally I'm a fan of team diving (and if you and your buddy plan to dive together most of the time then you have the right framework for it) so this means that you can carry enough gas for yourself to bailout from the bottom and deco gas can be split between you.

    I also went straight to doing CCR trimix. My opinion was that since I had a CCR and no intention on doing OC trimix dives and OC bailout was to be a major component of my training that doing OC trimix training and subsequent dives would not be money well spent. Others obviously disagree and if you want to take the slow, steady route and money is no object this is one way to go.

    As for choice of unit - there are lots of options varying from mCCR to eCCR and hybrid and everyone has their reasons for choosing one over another. I chose my unit because I wanted an electronically controlled CCR and because I was and am still hyper-vigilant at monitoring my PPO2, listening out for the sound of the solenoid, etc. I also chose it because I tend to break things and the Meg has the ability to manually plug in any of your offboard gas and proved to be virtually indestructible and capable of going as deep as you care to go (which for me is not all that deep, the 70m-80m range). Since buying my unit a local service facility has also become available in Queensland which is handy.

    My buddies dive Megs, Pelagians, KISSes, PRISMs, Optimas, and Inspirations and all appear to be happy with their choices apart from the latter (about half are constantly complaining about wiring problems and shoddy service from APD in the UK and are looking for an alternative).

  6. #6
    All IMVHO obviously... Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field has a reputation beyond repute Ben Field's Avatar
    Join Date
    Aug 2005
    Location
    Weymouth, England
    Posts
    3,023
    NVMCCR Inspiration

    Classic KISS, Sport KISS

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    My standpoint is common with some others expressed here about "when" a rebreather is worth considering, normally when you need one (for whatever reason) however in the last couple of years I've met two divers who went to rebreathers straight from PADI OW and are up to Trimix level now! I do wonder what will happen if as Mike points out they bailout at depth with their last OC experience being in less than 20mtrs but so far (touch wood) they seem okay...
    I find it alittle crazy you can learn on rebreather before learning basic underwater navigation and rescue skills but this is the system we have....

    While everyone above has given generic advice I'll be alittle more direct. (Although its all In My Very humble Opinion)

    1. Start on an MCCR- IMO this breeds an excellent mindset for a rebreather diver, "fear" trains you to monitor your PPO2 properly and the lack of a solenoid gives you a superb insight into the effects of depth, metabolism and activity on PPO2, loop volume etc.

    2. Servicing and Parts Support is vital, there is no point in having a £5000 bit of kit when spares are unobtainable (in a reasonable time frame) here in the Uk we are very lucky, there are so many divers we can borrow spares and the longest a part ever took to get here from jetsam was 48hrs, not sure how that effects you down under?

    3. If I where in the market right now I'd be looking at one of (what I call 3rd generation units) JJ, rEvo, Vision, they carry improvements learnt from the earlier days of recreational rebreather diving, proper testing and are "complete" out of the box (except for rEvo and lack of BOV, another essetial IMO) with simple electronics and built in deco. Redundacy is great but unless you intend to be miles back in caves its a false economy, when OW diving if in doubt BailOut to OC and fix your unit properly on the surface rather than arsing about at depth trying to fly a unit of secondaries or with issues- diving is supposed to be fun not hard work afterall!

    4. Again, just IMVHO but I would avoid older designs- Meg, KISS, Classic Inspiration, they contain a bunch of issues (which can be resolved) but why bother- go straight to somthing that works.

    5. Lastly I'd also avoid anything bespoke, rare or requiring unique spares that can be difficult to acquire, again- that might be a different situation in Oz to Uk so you'll have to discuss with the locals.

    6. Almost forgot- get a BOV, good instruction and if in doubt- Bail Out.

  7. #7
    RBW Member jlovold is a jewel in the rough jlovold is a jewel in the rough jlovold is a jewel in the rough jlovold is a jewel in the rough jlovold is a jewel in the rough jlovold is a jewel in the rough jlovold is a jewel in the rough jlovold's Avatar
    Join Date
    Jul 2006
    Location
    Sandnes, Norway
    Posts
    287
    rEvo III Micro FT

    Pelagian DCCCR

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    While I lack experience on other rebreathers (only a trydive on a Meg), I can highly recommend the Pelagian, as it is extremely compact and lightweight, very simple to run, and easily serviceable with off-the -shelf parts almost anywhere in the world.

    What is unique about the Pelagian is that it use a needle-valve to control the flow of oxygen (very easy to learn and use).

    It also has instant cell validation, (you exhale a bit of the loop-volume, and trigger the ADV by breathing in, letting the diluent blow across the cell-faces, giving you the PO2 of the diluent at depth, then all you need is to divide the PO2 with the pressure (30m=4ATM), and if everything is working correctly, the result should be the percentage of your diluent.

    If your readings are a bit off, you exhale a bit, and then inhale harder to blow moisture off the cell-faces. Works like a charm!

    And what sweetens the deal even more, is that it is small and light enough to take as carry-on-luggage. Including a bag and a few extra bits like swagelok QC-6, but without the x-plate, it was still only 12kgs, and would easily fit in the overhead compartment in most planes (tight fit in some, but doable).

  8. #8
    RBW Member sciron is an unknown quantity at this point sciron's Avatar
    Join Date
    May 2010
    Location
    Australia
    Posts
    2

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    Afternoon All,

    Apologies for the tardy response, and greatly appreciate all the feedback.

    As an FYI, I am currently working on more OC diving, probably aim for all of this year to clock up more bottom time and gradually increasing depth to continue to build experience before having a crack next year at CCR.

    (and of course i've started an agressive saving program to purchase a unit which will take me into next year :))

    Will continue to read, read and read and lurk around here to build a better understanding of the ins and outs of this endeavour.

    Again, thanks for all your time.

    Adam

  9. #9
    RBW Member kopaz is on a distinguished road kopaz is on a distinguished road kopaz's Avatar
    Join Date
    Jan 2009
    Location
    Denver, CO
    Posts
    148
    rEvo II

    Re: Obligatory 'Hi' and 'What should I buy' questions :)

    There is a lot to be said about getting OC skills honed. In fact I think these are vital.

    I would recommend getting some OC Normoxic Trimix experience before getting a rebreather... This will help you understand the trades better and it will give you the skills required to bailout and plan a bailout properly. A good grounding in tech diving would help.

    Another consideration is a rebreather has high entry cost and some additional fixed cost in maintenance with the O2 cells and what not, where OC cost is just gas and tank, regs & BC annuals.

    Bottom line is that you can treat an OC tech rig like a motorcycle or car, but you MUST treat a rebreather like an airplane.

    Airplanes and rebreathers require the same kind of commitment and attention to detail - the same mind set - to manage them safely.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts