+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 18

Thread: Replacing AutoAir for cave streamlining

  1. #1
    New Member CaveStainz is an unknown quantity at this point CaveStainz's Avatar
    Join Date
    Aug 2005
    Location
    UK, Kingston, Surrey
    Posts
    14

    Question Replacing AutoAir for cave streamlining

    Hi All,

    New to the forum, but been diving my Inspiration for a couple of years now and am looking to get my unit a bit more cave friendly. I've been cave diving open circuit for some time now and having been used to so much emphasis on streamlining i'm keen to hear how people are making their units snag free and easier to use in an overhead environment? (I should point out that i still need to attend a CCR cave upgrade course so i'm not looking to get the breather wet in an overhead environment for a couple of months so i've got some time to think things through).

    I'm just starting to give it some thought, but the areas that i'd want to work on first would be positioning of the handsets for least entanglement/maximum ease of use and how best to replace the AutoAir OC DV with a suitable kind of inflator for flat position?

    I use a Diverite Classic wing with short inflator on my OC setup, how easy is it to replace the AutoAir with something like this?

    How many people replace the AutoAir with a regular inflator and then double up with an OC dil reg plumbed into the onboard 1st stage? I'd normally use a stage and bailout reg, bit in confined space wouldn't a reg on a neck leash be safer as an additional option?

    I'd be keen to hear back from any one who can point me in the right direction..

    Cheers!

    Steve Walker

  2. #2
    Administrator ROB DAVIE has a spectacular aura about ROB DAVIE has a spectacular aura about ROB DAVIE has a spectacular aura about ROB DAVIE has a spectacular aura about ROB DAVIE has a spectacular aura about ROB DAVIE has a spectacular aura about ROB DAVIE's Avatar
    Join Date
    Feb 2005
    Location
    HOUSTON, REPUBLIC OF TEJAS
    Posts
    1,120
    While I have not been using my rig for cave diving, I can tell you that I replaced my original wing with a Dive Rite Superwing. It was easy to plumb both BC feed lines to the gas manifold. (You can get an M&J manifold with ten ports to replace the factory unit.)

    I plugged a 7 foot hose into the dil regulator and fed it out the top and to the right side with a TX-100 second stage on the business end. I have 7 liter cylinders on-board in a larger case.

    Nae problems, mate!

    Cheers!

    Rob

  3. #3
    Acme Serpentine Lubricant lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland's Avatar
    Join Date
    Mar 2005
    Location
    North...
    Posts
    2,372
    I had to bail out last week in the deep section of the Ressel after a Kenco moment on my KISS. I'm not convinced bailing out to onboard dil is really the way to go. I was on the onboard bottle for only a very short time in the deep section, pretty much the time it took to get on to my offboard OC stage. Once out of the deep section I went back on to the loop to do the deco and swim out. That few breaths of onboard gas was enough to compromise my dil supply for the rest of the dive so much that I didn't have enough left -- orally inflating my wing at the end. Caves can chew through dil, especially with the loop volume reduced in a flood, you don't have a huge control over your profile so you can get lots of dumping and adding where on a wreck you might not.

    I might be wrong, but my own feeling is that bailing out to onboard gas in a cave is a bad idea. After that dive I'd want to preserve my dil as much as possible if similar happened again, I think from now on I'll be bailing offboard straight away.

    I might be cynical but why would you need a cave RB cert? The only thing you really need to know is to try to flatten out the profile as much as possible e.g. go round rocks rather than over them, maximise your dil. Instead of thirds you plan your dive according to the amount of bail out you have, which isn't much different to open water. Zero vis, either trust your electronics or bail out, again could happen in open water so isn't anything new. Gas sharing... pass off a stage. Diving with an OC buddy, I'd be inclined to put a long hose on a stage reg and necklace it so that it can be easily donated prior to passing off the bottle. Neither of these are cave specific procedures either. Maybe the biggie, use OC when it is easier. Sounds a bit like a waste of money, but like I said I'm a cynic and as I'm sure will be pointed out, tight too.

    Cheers,

    Stuart

  4. #4
    New Member CaveStainz is an unknown quantity at this point CaveStainz's Avatar
    Join Date
    Aug 2005
    Location
    UK, Kingston, Surrey
    Posts
    14
    Great advice both of you! I'm not convinced either on the use of the inboard dil as a bailout option, i remember doing an OC ascent on the AutoAir as part of the course, and from 20m it doesn't leave you a lot of gas left after you've deployed an SMB and completed an ascent cracking the loop on the way up - it all takes time and the exercise proves how limited a 3L cylinder is! Multiply the problem with changes in depth within a cave and it probably won't work out well!

    I like the idea of a longer hose on the stage cylinder - it's something that I've seen instructors do for the benefit of their students so it really could just as easily apply for buddies.

    On the question of whether or not a CCR Cave course is *required* I would have to say that on the whole most people who have been on a fundamentals cave course don't seem to have moved their training on formally to the other qualifications. I have struggled to find anyone else who wants to attend a course on CCR Cave Trimix.

    If you accept that on some dives your rebreather will not be kind to you, it's a question of whether or not you can say hand on heart that your buoyancy is good enough to keep you out of trouble if the wheels fall off and that you have enough bailout gas to manage an OC exit and honour your deco. I think my buoyancy is good enough on OC dives, but should i ever find myself in a situation where the shit hits the fan I'd hate to think that the one thing that would have got me out alive was a skill that is practised in a CCR cave course and I didn't know it!

    I suppose it's a calculated risk, my ultimate aim is to dive CCR in trimix depths within caves - the blue wobbly stuff doesn't hold my interest as much... so if i'm serious about doing it properly shouldn't i do a course? I've completed over a 100 cave dives in France and Florida, side mount dives in the UK - and i'm still learning!

    I hope to provoke a discussion on this, but maybe not within the Inspiration thread!

    Steve


  5. #5
    Jani Haaja jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja is just really nice jhaaja's Avatar
    Join Date
    Mar 2005
    Location
    Finland
    Posts
    978
    JJ-CCR, Inspo Classic

    HH Inspo

    I have an OC reg connected to the YBOD dil manifold. I hang it under my chin. I think it is good to have the possibility to go OC as fast as possible for a few breaths. This can be done from the 3L tank. The tank is too small for bailing out from a cave, but for a breaths to clear your head and identify the problem you are facing it is OK.

    I also keep my bail-out stage valve partly open, so that I can get that gas also quickly to use. I am also considering a LP-inflator hose to be fitted to the bail-out stages reg. This would be nice if your on-boar dil gets low. I could plug it to the manual dil button and at least get gas in to the loop.

    JH
    FInland

  6. #6
    PFO free :) pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning is just really nice pchanning's Avatar
    Join Date
    Feb 2005
    Location
    fixed!
    Posts
    454

    some options

    Hi Steve,

    how about using AP's GCS off the stage to the ADV and go open loop, which is better than a neck laced 2nd stage. Obviously the integrity of you're loop is critical as is a sound scrubber, but it would get you through the shit.

    I managed to make most of the GCS from bits and pieces I had lying around (auto air inflators and a long reg hose). The only bit I bought was the male connector from AP, costing me about £20 IIRC. Laughing..!! Its a good cheap Mod.

    Keep the long hose 2nd stage for others and a LP whip for you're CL's and drysuit.



    Ultimately a BOV (Bail Out Valve) is the preferred choice. There are discussions in other threads about them. They are certainly the way to go for tight, low-profile environments. Plugged into you're offboard in a zero viz constriction you can't go wrong.

    Maximum integrity (safety) no swopping, no fumbling, no stress, just a twist for safe gas to get you through the shit.

    Just some thoughts, hope they help.

    cheers

    paul

  7. #7
    EXPLORER jdz has a spectacular aura about jdz has a spectacular aura about jdz has a spectacular aura about jdz has a spectacular aura about jdz has a spectacular aura about jdz's Avatar
    Join Date
    Feb 2005
    Location
    Melbourne Australia
    Posts
    305
    rEvo, PRISM, KISS

    Modccr Dolphin, SM CCR, Satori

    My take on this is as most have implied, keep your bailout gas separate and offboard.

    I dive a Prism & I use two OC sidemounts, 7 or 10lts depending on distance/depth etc. and I use standard setups on each unit, reg/lp inflator and guage. The inflators give me the ability to plug into my rb if I need extra dil. I am keenly looking at the BOV alternatives. I removed the supplied wing/harness and substituted them with my transpac2 and wing, eliminating the Air2. I've attached a photo.

    For cavediving, I would recommend the bailouts to be sidemounted rather than slung and hence sidemount training and/or experience would go a long way. In OZ, advanced cavediving techniques (such as sidemounting) are workshopped rather than setup in the mainstream training structure.

    Cheers, JDZ
    Attached Images

  8. #8
    New Member CaveStainz is an unknown quantity at this point CaveStainz's Avatar
    Join Date
    Aug 2005
    Location
    UK, Kingston, Surrey
    Posts
    14

    Question

    Hi All,

    Thanks for all of your comments! Looks like you all favour a compromise between inboard gas for normal operation plus offboard plug in for manual dil inflation and ADV.. In a way this isn't far away from where i am today, having long switched off my ADV preferring manual dil addition. I think this makes for better MLV control anyway and more awareness in changes of depth.

    The main decision therefore comes from whether to retrofit a DiveRite/Zeagle inflator onto the existing Buddy wing, or replace the whole thing with a DiveRite BC and be done with it!

    I still didn't find out whether it is a 15mins job to fit an alternative inflator once the AutoAir is removed?

    In either case i'll need to do some research into whether the GCS or Swagelok would be appropriate for offboard ADV supply?

    Any favourites? It seems to me that if I don't use the ADV that often and am used to manual dil addition during normal dives I could just leave it plugged inboard and isolated and carry out manual addition permanently from my offboard stage?

    I guess all of these things might be covered in a CCR cave course, but they were covered well on my MOD2 course and i'm still concerned a little as to whether there is very much more to learn that is specific to CCRs when cave diving according to Stuart's comment?

    If the mantra is to conserve your diluent throughout the profile, retain copious offboard diluent supply, and always have enough OC gas to complete your exit and decompression - maintaining graceful buoyancy throughout, >>have i understood 5% or 50%!!?

    Obviously that's a little tongue in cheek, but going back to my initial comment, i can't seem to find anyone who wants to go on a CCR Trimix cave course, since everyone seems to have skipped this step!

    Take care,

    Steve

  9. #9
    Submerge Productions PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver is a splendid one to behold PCDiver's Avatar
    Join Date
    Feb 2005
    Location
    Malta (Rabat)
    Posts
    1,178
    I still didn't find out whether it is a 15mins job to fit an alternative inflator once the AutoAir is removed?
    It depends. If you still want to use the "pull the hose to dump air"-function it will take longer. I haven't tried this myself. If you just replace the inflator it is a 15 minute job. I used a Halcyon wing inflator and a tie-wrap to secure the inflator to the hose.

    You need either a connector between the APD LP hose and the inflator or canibalise a normal inflator hose. A normal inflator hose does not connect to the manifold. You can remove the connector from the APD LP hose and attach it to the LP inflator hose.

    Remember that if you don't have an inflator on the on-board diluent system, you have to add an overpressure relief valve.

  10. #10
    Acme Serpentine Lubricant lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland has a reputation beyond repute lizardland's Avatar
    Join Date
    Mar 2005
    Location
    North...
    Posts
    2,372
    I've got some Swagelok bits and pieces lying around for offboard gas hook ups but haven't got around to it. Still not sure if it's a good idea or not, you can always breathe offboard gas into the loop without introducing another failure point. I guess the question is, is there more chance of the offboard connection screwing up or screwing up the loop by breathing a whiff from your offboard gas into the loop manually. I suppose it's easier to hook up gas on the YBOD than the KISS, I guess you can just connect into the manual dil valve. Doesn't AP recommend against using the GCS system for OC reg connections below 40m? I mistakenly bought QC4's, these also look too narrow. I'd go for the QC6's.

    Thinking about it, I should really have taken the time to shut down the dil and O2 when I bailed but when Mr Murphy calls he can be very distracting company on a dive. I guess the same goes for buoyancy control... crippled sparrow I believe was the term used afterwards :)

    I've only used the KISS on 15 or so cave dives (about 9 years OC cave diving) so I'm maybe not an authority on whether or not a course is justified, personally I think it is a hell of a lot safer than OC in the right cave. I'd imagine if you can dive OC in a cave then using a RB is a step down in the difficulty stakes. On the other hand, sometimes a twinset is a much simpler option.

    My KISS is rigged pretty much exactly as my OC twinset was so I prefer to have my stages sideslung, and, ashamed to admit it, both worn on the left, DIR stylee (ally 7's or 12's). I've seen people with hard-mounted bottles on the sides of their rigs, it wouldn't be my choice for cave diving, but each to their own and I'm not about to start telling people they're wrong. If it works then it works. After diving my bagpipes of doom homebuild, I can't knock anyone :)

+ Reply to Thread
Page 1 of 2 1 2 LastLast

Posting Permissions

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