Suitability of varying rebreathers for cave diving

dive2dive2000 · 6th September 2005, 01:39

Matt good to see you on Rebreather World. You gave me a wirl on your MEG back in April

Martin

BTW I start CCR class on Saturday

***caveseeker7*** · 6th September 2005, 16:15

Quote: (Originally Posted by mattmexico)

What I hate the most, and I have no real remedy against is the fact that if I have to go to bail out I am forced back onto OC and that ticking, bubbling issue of diminishing gas supply ... and blown or prolonged deco schedule ... if there is one. I still don't have the perfect bail out CCR but hate the most going back onto OC.

Matt, wasn't the dual Cis dual for backup?
So you're familiar with the idea of a dual rebreather.

You dive the Meg. You dive the Oh-tooptima.

Throw out the big 4 ltr jugs, mount the Meg onto the Oh Tooptima and off you go.

Two supply tanks for the DiveRite can be sidemounted ... give it a try and let us know.

mattmexico · 9th September 2005, 00:32

[quote=caveseeker7]Matt, wasn't the dual Cis dual for backup?
So you're familiar with the idea of a dual rebreather.

You dive the Meg. You dive the Oh-tooptima.

Throw out the big 4 ltr jugs, mount the Meg onto the Oh Tooptima and off you go.

Two supply tanks for the DiveRite can be sidemounted ... give it a try and let us know.

Yep

I loved the Dual Cis. we did gas depots up to 8000 feet or so but then went to double Cis for bail out. Great stuff, never felt better deep underground. We could have walked out if we wanted to.

Steve Bogaerts was diving a double Inspiration mounted on a steel frame in the Pit exploration with bottom time exeeding 1 hour to a depth exeeding 330 feet - 100 meters.

Olivier Isler did his record breaking dives years back on 3 breathers, and I think that's the way to go, in terms of redundancy.

Meg - Optima ( diving the Optima with 2 ltr steel's ) combo sounds good. O2 on the side, maybe two for redundancy, larger sidemount tanks for dilluent or in case you need to drop it all and do a little no-mount excursion ... just kidding.

Counterlung cluster is becoming an issue. On the double Cis we had the two sets of counterlungs in front, after some time one is getting used to it. I think Steve Bogaerts told me he had one set of counterlungs in front of his shoulder and one set behind his shoulder. I can see that too, should not be to difficult to pull them out and use them if needed.

A word of caution if you like your tounge. When diving the double Cis in the beginning during trials I had a hard lesson to learn. When descending with the twins you need to inflate the second unit or it may create a vacuum. One day I did a switch and had not sufficiently inflated the second unit, the moment I opened the DSV my tounge was sucked into the mouth piece. Very painfull. Only with great force and inflating the unit I could retrieve my tounge, while not being able to breathe ... its blocked by my tongue right. If I would have been in a uncontrolled descent I would probably have drowned. I damaged one of the Cis corrugated hosees as well during this vacuum trial. Ouch ...

What we did as well was diving the backup unit on the way down, make sure its working allright, has the right po2, computers working, right gases selected in the deco software and so on. The primary unit was inflated with diluent. When getting to max depth doing the switch we then verified the primary unit was working properly with po2, gases plugged in, gases set in the deco software and then went on for the dive. That left us to know the backup unit is ready to roll when needed.

Matt
www.protecdiving.com

***caveseeker7*** · 9th September 2005, 03:01

Quote: (Originally Posted by mattmexico)

A word of caution if you like your tounge.

Yes I do, and I'm not the only one.

That is one of the funniest dive stories I've ever heard, Matt, thanks for telling.
Green for the story and the diving.

You must have quite a tongue damaging the hoses ...

... think you can trash the Halcyon's Cooper hoses, too?

We could have walked out if we wanted to is another line I'll remember. There is much to said for dual RBs for extreme diving. Thanks for the protocol regarding the dives, it's a question that usually comes up when discussing the topic.

MikeH · 9th September 2005, 04:00

Quote: (Originally Posted by mattmexico)

Meg - Optima ( diving the Optima with 2 ltr steel's ) combo sounds good. O2 on the side, maybe two for redundancy, larger sidemount tanks for dilluent or in case you need to drop it all and do a little no-mount excursion ... just kidding.

I have thought about the Megalodon and KISS being combined into a single unit....with the scrubber canisters being on your back almost like doubles, then the O2 cylinders being just on the outside of each scrubber, and the 2 diluent cylinders being rigged as sidemounts(steel 50cf cylinders would be perfect for this, and provide some reasonable size OC bailout). The nice thing about the KISS, in this configuration, is that the counterlungs are on your back....which eliminates the bulk of double OTS counterlungs.

Just a thought....

Mike

decoweenie · 9th September 2005, 04:46

Quote: (Originally Posted by mattmexico)

...When descending with the twins you need to inflate the second unit or it may create a vacuum. One day I did a switch and had not sufficiently inflated the second unit, the moment I opened the DSV my tounge was sucked into the mouth piece...

Hi Matt,

The Cis does have an ADV right ? Why didn't the ADV inflate the back-up unit on descent ?

mattmexico · 9th September 2005, 17:29

Quote: (Originally Posted by decoweenie)

Hi Matt,

The Cis does have an ADV right ? Why didn't the ADV inflate the back-up unit on descent ?

Yes, you are right, the Cis does have a ADV, sure enough, its located in the counterlung. Mhhmmm. Don't remember why it did not inflate. Maybe it was not activated .... can't remember, memory lane is not that bright today.

When developing the double units one of the earlyer designs had one unit on the back and the second on the scooter. Looked good, only problem might be that if you have to ditch the scooter, the unit goes too.

While on a trade show in Germany two years back some guys showed a refined RB80 copy ( Deep Access ) presented as a double unit. Looked like a set of alm 80 doubles on the back with two sidemounted tanks for dil and o2. That looked pretty good.

You could to the same with almost any ccr I would think, just buy two ( happy hour ), mount them side by side and see what gas and tanks you need, bracket mounted to the unit and / or side mounted.

Matt
www.protecdiving.com

***caveseeker7*** · 9th September 2005, 19:50

Quote: (Originally Posted by mattmexico)

While on a trade show in Germany two years back some guys showed a refined RB80 copy ( Deep Access ) presented as a double unit. Looked like a set of alm 80 doubles on the back with two sidemounted tanks for dil and o2. That looked pretty good.

You could to the same with almost any ccr I would think, just buy two ( happy hour ), mount them side by side and see what gas and tanks you need, bracket mounted to the unit and / or side mounted.

Matt, we've been discussing dual and multiple rebreathers in the perfect bailout Rebreather thread, if you want to have a look.

Quote:

... the Cis does have a ADV, sure enough, its located in the counterlung ...

Naaah, the Cis just really sucks.

db8us · 14th September 2005, 20:33

Hi Matt, Stefan,Phi, Zak etc.

i want to add that i think the RB80 is not a bad unit for cave-diving, but maybe i am biased ;-)

Michael

guy · 14th September 2005, 22:33

Jim Bowden uses a VOYAGER rebreather for his cave diving explorations. Also, I know the VOYAGER was designed by Italian Cave Diver, Nicola Donda. Apparently, he is a extremely experienced cold water cave explorer and he specifically designed the rebreather for this purpose - furthermore, they have specific Cave Diver course for the unit. The counterlungs and scrubber canister can be fitted with a one-way valves for purging out condensation. Also, I heard a rumour that someone will be using a VOYAGER in October to make a world-record cave dive.

6th September 2005, 01:39	#41 (permalink)
dive2dive2000 PRISM DIVER & LUVIN IT! Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Feb 2005 Location: Long Island, NY Posts: 775	Matt good to see you on Rebreather World. You gave me a wirl on your MEG back in April Martin BTW I start CCR class on Saturday
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6th September 2005, 16:15	#42 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,281	Quote: (Originally Posted by mattmexico) What I hate the most, and I have no real remedy against is the fact that if I have to go to bail out I am forced back onto OC and that ticking, bubbling issue of diminishing gas supply ... and blown or prolonged deco schedule ... if there is one. I still don't have the perfect bail out CCR but hate the most going back onto OC. Matt, wasn't the dual Cis dual for backup? So you're familiar with the idea of a dual rebreather. You dive the Meg. You dive the Oh-tooptima. Throw out the big 4 ltr jugs, mount the Meg onto the Oh Tooptima and off you go. Two supply tanks for the DiveRite can be sidemounted ... give it a try and let us know. __________________ Cheers Stefan Be Water, My Friend - Bruce Lee Sponsor Lou in Race For Life!
(Offline)

9th September 2005, 00:32	#43 (permalink)
mattmexico Rebreather World Writer Current Rebreather/s: Megalodon Classic Kiss Optima RB80 / Clone Other Rebreather/s: Inspiration Classic Evolution Prism Topaz Sport Kiss RB80 / Clone Join Date: Aug 2005 Location: Mexico, Q.Roo, Playa del Carmen Posts: 696	[quote=caveseeker7]Matt, wasn't the dual Cis dual for backup? So you're familiar with the idea of a dual rebreather. You dive the Meg. You dive the Oh-tooptima. Throw out the big 4 ltr jugs, mount the Meg onto the Oh Tooptima and off you go. Two supply tanks for the DiveRite can be sidemounted ... give it a try and let us know. Yep I loved the Dual Cis. we did gas depots up to 8000 feet or so but then went to double Cis for bail out. Great stuff, never felt better deep underground. We could have walked out if we wanted to. Steve Bogaerts was diving a double Inspiration mounted on a steel frame in the Pit exploration with bottom time exeeding 1 hour to a depth exeeding 330 feet - 100 meters. Olivier Isler did his record breaking dives years back on 3 breathers, and I think that's the way to go, in terms of redundancy. Meg - Optima ( diving the Optima with 2 ltr steel's ) combo sounds good. O2 on the side, maybe two for redundancy, larger sidemount tanks for dilluent or in case you need to drop it all and do a little no-mount excursion ... just kidding. Counterlung cluster is becoming an issue. On the double Cis we had the two sets of counterlungs in front, after some time one is getting used to it. I think Steve Bogaerts told me he had one set of counterlungs in front of his shoulder and one set behind his shoulder. I can see that too, should not be to difficult to pull them out and use them if needed. A word of caution if you like your tounge. When diving the double Cis in the beginning during trials I had a hard lesson to learn. When descending with the twins you need to inflate the second unit or it may create a vacuum. One day I did a switch and had not sufficiently inflated the second unit, the moment I opened the DSV my tounge was sucked into the mouth piece. Very painfull. Only with great force and inflating the unit I could retrieve my tounge, while not being able to breathe ... its blocked by my tongue right. If I would have been in a uncontrolled descent I would probably have drowned. I damaged one of the Cis corrugated hosees as well during this vacuum trial. Ouch ... What we did as well was diving the backup unit on the way down, make sure its working allright, has the right po2, computers working, right gases selected in the deco software and so on. The primary unit was inflated with diluent. When getting to max depth doing the switch we then verified the primary unit was working properly with po2, gases plugged in, gases set in the deco software and then went on for the dive. That left us to know the backup unit is ready to roll when needed. Matt www.protecdiving.com
(Offline)

9th September 2005, 03:01	#44 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,281	Rofl !!! Quote: (Originally Posted by mattmexico) A word of caution if you like your tounge. Yes I do, and I'm not the only one. That is one of the funniest dive stories I've ever heard, Matt, thanks for telling. Green for the story and the diving. You must have quite a tongue damaging the hoses ... ... think you can trash the Halcyon's Cooper hoses, too? We could have walked out if we wanted to is another line I'll remember. There is much to said for dual RBs for extreme diving. Thanks for the protocol regarding the dives, it's a question that usually comes up when discussing the topic. __________________ Cheers Stefan Be Water, My Friend - Bruce Lee Sponsor Lou in Race For Life!
(Offline)

9th September 2005, 04:00	#45 (permalink)
MikeH Custom Title Allowed! Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Aug 2005 Location: Orlando, FL USA Posts: 178	Quote: (Originally Posted by mattmexico) Meg - Optima ( diving the Optima with 2 ltr steel's ) combo sounds good. O2 on the side, maybe two for redundancy, larger sidemount tanks for dilluent or in case you need to drop it all and do a little no-mount excursion ... just kidding. I have thought about the Megalodon and KISS being combined into a single unit....with the scrubber canisters being on your back almost like doubles, then the O2 cylinders being just on the outside of each scrubber, and the 2 diluent cylinders being rigged as sidemounts(steel 50cf cylinders would be perfect for this, and provide some reasonable size OC bailout). The nice thing about the KISS, in this configuration, is that the counterlungs are on your back....which eliminates the bulk of double OTS counterlungs. Just a thought.... Mike
(Offline)

9th September 2005, 04:46	#46 (permalink)
decoweenie Crash Test Dummy Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Feb 2005 Location: Cairo Posts: 5,509	Quote: (Originally Posted by mattmexico) ...When descending with the twins you need to inflate the second unit or it may create a vacuum. One day I did a switch and had not sufficiently inflated the second unit, the moment I opened the DSV my tounge was sucked into the mouth piece... Hi Matt, The Cis does have an ADV right ? Why didn't the ADV inflate the back-up unit on descent ? __________________ "...after a while you get bored offering advice to a bull that like to keep butting the fence with its head rather than walking through the open gate..." - Rebreather World PM
(Offline)

9th September 2005, 17:29	#47 (permalink)
mattmexico Rebreather World Writer Current Rebreather/s: Megalodon Classic Kiss Optima RB80 / Clone Other Rebreather/s: Inspiration Classic Evolution Prism Topaz Sport Kiss RB80 / Clone Join Date: Aug 2005 Location: Mexico, Q.Roo, Playa del Carmen Posts: 696	Quote: (Originally Posted by decoweenie) Hi Matt, The Cis does have an ADV right ? Why didn't the ADV inflate the back-up unit on descent ? Yes, you are right, the Cis does have a ADV, sure enough, its located in the counterlung. Mhhmmm. Don't remember why it did not inflate. Maybe it was not activated .... can't remember, memory lane is not that bright today. When developing the double units one of the earlyer designs had one unit on the back and the second on the scooter. Looked good, only problem might be that if you have to ditch the scooter, the unit goes too. While on a trade show in Germany two years back some guys showed a refined RB80 copy ( Deep Access ) presented as a double unit. Looked like a set of alm 80 doubles on the back with two sidemounted tanks for dil and o2. That looked pretty good. You could to the same with almost any ccr I would think, just buy two ( happy hour ), mount them side by side and see what gas and tanks you need, bracket mounted to the unit and / or side mounted. Matt www.protecdiving.com
(Offline)

9th September 2005, 19:50	#48 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,281	Quote: (Originally Posted by mattmexico) While on a trade show in Germany two years back some guys showed a refined RB80 copy ( Deep Access ) presented as a double unit. Looked like a set of alm 80 doubles on the back with two sidemounted tanks for dil and o2. That looked pretty good. You could to the same with almost any ccr I would think, just buy two ( happy hour ), mount them side by side and see what gas and tanks you need, bracket mounted to the unit and / or side mounted. Matt, we've been discussing dual and multiple rebreathers in the perfect bailout Rebreather thread, if you want to have a look. Quote: ... the Cis does have a ADV, sure enough, its located in the counterlung ... Naaah, the Cis just really sucks. __________________ Cheers Stefan Be Water, My Friend - Bruce Lee Sponsor Lou in Race For Life!
(Offline)

14th September 2005, 20:33	#49 (permalink)
db8us Custom Title Allowed! Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Sep 2005 Location: Germany Posts: 223	Hi Matt, Stefan,Phi, Zak etc. i want to add that i think the RB80 is not a bad unit for cave-diving, but maybe i am biased ;-) Michael
(Offline)

14th September 2005, 22:33	#50 (permalink)
guy New Member Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Sep 2005 Location: SCOTLAND, Edinburgh Posts: 21	Jim Bowden uses a VOYAGER rebreather for his cave diving explorations. Also, I know the VOYAGER was designed by Italian Cave Diver, Nicola Donda. Apparently, he is a extremely experienced cold water cave explorer and he specifically designed the rebreather for this purpose - furthermore, they have specific Cave Diver course for the unit. The counterlungs and scrubber canister can be fitted with a one-way valves for purging out condensation. Also, I heard a rumour that someone will be using a VOYAGER in October to make a world-record cave dive.
(Online)

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