BOV Gas Supply

pchanning · 3rd April 2006, 12:18

Quote: (Originally Posted by caveseeker7)

Neat, ain't it.

Its brilliant! Trouble is, I cant work it out at 1 ata

1 switch for me - stoopid is as stoopid does

diverklondike · 3rd April 2006, 13:27

Mike,

Lots of good points... Comments below...

Quote: (Originally Posted by Drmike)

Hi,

Will you be adding check valves (one way valves) into the offboard and the onboard feed hoses? Do you think that will effect the WOB at depth?

*** I am still considering the pros and cons... As you have suggested there is a potential WOB issue at depth.

Another much simpler way would be just to have 2 QC hoses, one off the dil and one off the off board.

*** In some ways yes... One issue is how to keep the routing and access clean. I have seen the example on the site that several people have mentioned.

To me I think your way adds too much uneccessary risk with no real benefit over just simply having 2 QC hoses.

*****************************************
What happens if you forget to turn off the supply you are not going to breathe from?

What happens if (you have no check valves and) the supply you are not breathing from is turned on - cross mixing of gases? Ok if same mix but what if this happens when its different mixes? Could this compromise both Rebreather and bail out supplies?

*** I see your point but I think its a managable risk... BTW... It's my understanding that the configuration for the Boris has this same issue with offboard gas. You will need to remember to turn off your onboard dil before having a charged offboard line plugged into the rig.

************************************************** **

I believe using a swicthblock adds even more risk that you switch to the wrong gas! Why add the risk? What is the benefit? a 3 second faster switch???

is having a super fast switch time critical??

Myself I dont see the benefit of manifolded on/off board supplies (or use of switchblock) but I do see risk.

To me KISS, plug and play hose with QC - easy to verify yourself and by a buddy what supply you are breathing from and no common failure points.

FWIW my inspiration was set up just like Simons -
http://www.rebreatherworld.com/rebre...atics-bov.html I found it easy and simple to use.

cheers
Mike

Great conversation all the way around... Once I get the BOV I will be trying several different approaches to hose routing connection approaches etc..

With all of the people considering BOVs on the list I am sure there will be lots of good ideas and feedback to share....

Dive Safe...

Mark

Drmike · 3rd April 2006, 15:09

Quote: (Originally Posted by diverklondike)

Mike,

Lots of good points... Comments below...

Great conversation all the way around... Once I get the BOV I will be trying several different approaches to hose routing connection approaches etc..

With all of the people considering BOVs on the list I am sure there will be lots of good ideas and feedback to share....

Dive Safe...

Mark

Hi Mark,

Yes the boris has plugs for off board dil and O2 - but plug the wrong gas in and the controller will alert you if the ppo2 is life threatening (you may get bent worse case but not dead) The same safety net isnt there with OC bail gas - so I think its best to make it as idiot proof as possible. To me that means just like OC, we have physical switches (plug in gas when needed) and not manifolds or switch blocks that could much easier lead to diver error (Switching valve (or tank valves on/off) to a hyperoxic gas by accident.

Half the fun is experimenting and modifying gear. My set up changes less and less these days but it still evolves.

Cheers
Mike

divetheworld · 3rd April 2006, 17:49

Quote: (Originally Posted by Drmike)

Hi,

I believe using a swicthblock adds even more risk that you switch to the wrong gas! Why add the risk? What is the benefit? a 3 second faster switch???

is having a super fast switch time critical??

Myself I dont see the benefit of manifolded on/off board supplies (or use of switchblock) but I do see risk.

cheers
Mike

Hey Mike, how you doing?
Thought I might just pass on my comment, another point of view that might shine some light on the use of a SB.
A switchblock can give you access to two inboard gas supplies with only one regulator. If your the kind of guy who uses a bail reg to the Dil and O2, this is better IMHO.
I use a switchblock connected to an external regulator and to the GCS. system. This way I can use the DIL, O2 or even disconnect and plug into offboard at will. Pictures of the old box (similar config) see - http://homepage.ntlworld.com/brent.h...tch/switch.htm

Advantages;

More flexible bail using inboard in the plan.
Less chance of a freeflow causing loss of O2, default position is DIL.
No additional failure points, less likely to fail than two regs.
Safer Alpinist at shallow depths.

Disadvantages;

Requires more mental discipline.
Cost

If you have the mental discipline to use it, I see it as a better option.
In summary, its not the speed of switch, its the one reg, two supplies.

One more thing, I have had a few experiences of the GCS sticking open when disconnected and having to gas shut down. I dont like to unplug unless I absolutely have to or the gas is turned off/depleated.

Generally commenting to the thread;
My opinion, I use it and I'm not hypothesizing. I've used it at beyond EN250 depths and got favourable results. On my stage/s I have a single Pozzi Xstream (long hose) and one GCS femail short LP hose.
Not every one will agree with my philosophy, but thats the beauty of personal configuration.
p.s. I also use a flow stop on the BOV, http://homepage.ntlworld.com/brent.h...er/bov/bov.htm the first two pictures show it fitted. The yellow BOB on the left is on the home build Dolphin and the black BOB on the right is on my AP unit.

Brent.

Janos · 3rd April 2006, 21:35

Have patience with this

but how likely are GCS to fail when nothing is plugged into them? I'm half-heartedly thinking about putting a GCS into the manifold (which feeds both the ADV and the BOV) which would normally be unplugged. If I needed to bail then I would go OC, before plugging in the stage to go SCR at the first stop.

Downsides are the faff factor and the additional failure point. The faff factor could be minimised by having a longish hose which is tucked neatly away (you're not going to have to restow it) but I can see the merits in keeping things as simple as possible.

Janos

divetheworld · 3rd April 2006, 22:03

Quote: (Originally Posted by Janos)

Have patience with this

but how likely are GCS to fail when nothing is plugged into them? I'm half-heartedly thinking about putting a GCS into the manifold (which feeds both the ADV and the BOV) which would normally be unplugged. If I needed to bail then I would go OC, before plugging in the stage to go SCR at the first stop.

Downsides are the faff factor and the additional failure point. The faff factor could be minimised by having a longish hose which is tucked neatly away (you're not going to have to restow it) but I can see the merits in keeping things as simple as possible.

Janos

Just from my own experience, Popped one off to switch underwater and it did not seal. Stripped and put in the ultrasonic bath, perfect. Two months later when on the bench, popped it off, stuck again. The female on the stage has never failed, but is not connected unless bailing for (fun) practice.
I concluded that the internal seal has a tendency to stick if it is not used and left connected. I'm happy to have them as they serve a good purpose but when I disconnect, I am prepared to shut down straight away, especially if that gas is depleted.

Best,
Brent.

3rd April 2006, 12:18	#21 (permalink)
pchanning PFO free :) Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2005 Location: fixed! Posts: 454	Re: BOV Gas Supply Quote: (Originally Posted by caveseeker7) Neat, ain't it. Its brilliant! Trouble is, I cant work it out at 1 ata 1 switch for me - stoopid is as stoopid does __________________ Cheers Paul The key to enlightenment... is survival.
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3rd April 2006, 13:27	#22 (permalink)
diverklondike Just one of the Peasants Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Inspiration Classic Other CCR Join Date: Oct 2005 Location: Delaware, USA Posts: 1,611	Re: BOV Gas Supply Mike, Lots of good points... Comments below... Quote: (Originally Posted by Drmike) Hi, Will you be adding check valves (one way valves) into the offboard and the onboard feed hoses? Do you think that will effect the WOB at depth? * I am still considering the pros and cons... As you have suggested there is a potential WOB issue at depth. Another much simpler way would be just to have 2 QC hoses, one off the dil and one off the off board. * In some ways yes... One issue is how to keep the routing and access clean. I have seen the example on the site that several people have mentioned. To me I think your way adds too much uneccessary risk with no real benefit over just simply having 2 QC hoses. *************************************** What happens if you forget to turn off the supply you are not going to breathe from? What happens if (you have no check valves and) the supply you are not breathing from is turned on - cross mixing of gases? Ok if same mix but what if this happens when its different mixes? Could this compromise both Rebreather and bail out supplies? * I see your point but I think its a managable risk... BTW... It's my understanding that the configuration for the Boris has this same issue with offboard gas. You will need to remember to turn off your onboard dil before having a charged offboard line plugged into the rig. ************************************************ I believe using a swicthblock adds even more risk that you switch to the wrong gas! Why add the risk? What is the benefit? a 3 second faster switch??? is having a super fast switch time critical?? Myself I dont see the benefit of manifolded on/off board supplies (or use of switchblock) but I do see risk. To me KISS, plug and play hose with QC - easy to verify yourself and by a buddy what supply you are breathing from and no common failure points. FWIW my inspiration was set up just like Simons - http://www.rebreatherworld.com/rebre...atics-bov.html I found it easy and simple to use. cheers Mike Great conversation all the way around... Once I get the BOV I will be trying several different approaches to hose routing connection approaches etc.. With all of the people considering BOVs on the list I am sure there will be lots of good ideas and feedback to share.... Dive Safe... Mark
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3rd April 2006, 15:09	#23 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,322	Re: BOV Gas Supply Quote: (Originally Posted by diverklondike) Mike, Lots of good points... Comments below... Great conversation all the way around... Once I get the BOV I will be trying several different approaches to hose routing connection approaches etc.. With all of the people considering BOVs on the list I am sure there will be lots of good ideas and feedback to share.... Dive Safe... Mark Hi Mark, Yes the boris has plugs for off board dil and O2 - but plug the wrong gas in and the controller will alert you if the ppo2 is life threatening (you may get bent worse case but not dead) The same safety net isnt there with OC bail gas - so I think its best to make it as idiot proof as possible. To me that means just like OC, we have physical switches (plug in gas when needed) and not manifolds or switch blocks that could much easier lead to diver error (Switching valve (or tank valves on/off) to a hyperoxic gas by accident. Half the fun is experimenting and modifying gear. My set up changes less and less these days but it still evolves. Cheers Mike __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
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3rd April 2006, 17:49	#24 (permalink)
divetheworld Dive porn pimp Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Not Bought Yet Inspiration Classic Inspiration Vision Classic Kiss Other CCR Join Date: Mar 2005 Location: Leeds, England Posts: 1,586	Re: BOV Gas Supply Quote: (Originally Posted by Drmike) Hi, I believe using a swicthblock adds even more risk that you switch to the wrong gas! Why add the risk? What is the benefit? a 3 second faster switch??? is having a super fast switch time critical?? Myself I dont see the benefit of manifolded on/off board supplies (or use of switchblock) but I do see risk. cheers Mike Hey Mike, how you doing? Thought I might just pass on my comment, another point of view that might shine some light on the use of a SB. A switchblock can give you access to two inboard gas supplies with only one regulator. If your the kind of guy who uses a bail reg to the Dil and O2, this is better IMHO. I use a switchblock connected to an external regulator and to the GCS. system. This way I can use the DIL, O2 or even disconnect and plug into offboard at will. Pictures of the old box (similar config) see - http://homepage.ntlworld.com/brent.h...tch/switch.htm Advantages; More flexible bail using inboard in the plan. Less chance of a freeflow causing loss of O2, default position is DIL. No additional failure points, less likely to fail than two regs. Safer Alpinist at shallow depths. Disadvantages; Requires more mental discipline. Cost If you have the mental discipline to use it, I see it as a better option. In summary, its not the speed of switch, its the one reg, two supplies. One more thing, I have had a few experiences of the GCS sticking open when disconnected and having to gas shut down. I dont like to unplug unless I absolutely have to or the gas is turned off/depleated. Generally commenting to the thread; My opinion, I use it and I'm not hypothesizing. I've used it at beyond EN250 depths and got favourable results. On my stage/s I have a single Pozzi Xstream (long hose) and one GCS femail short LP hose. Not every one will agree with my philosophy, but thats the beauty of personal configuration. p.s. I also use a flow stop on the BOV, http://homepage.ntlworld.com/brent.h...er/bov/bov.htm the first two pictures show it fitted. The yellow BOB on the left is on the home build Dolphin and the black BOB on the right is on my AP unit. Brent. __________________ Attitude and self praise is no reccomendation. Dont try to be a great man, just be a man and let history be the judge of you. CHECK OUT OUR INTERWEBS FOR CUSTOM REBREATHER UPGRADES *WWW.NARKEDAT90.CO.UK* *http://www.grpservices.com/pursuit/* Supporting Shearwater Research Products in Europe Last edited by divetheworld : 3rd April 2006 at 19:00.
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3rd April 2006, 21:35	#25 (permalink)
Janos "Two Sheds" Current Rebreather/s: Classic Kiss Other Rebreather/s: Classic Kiss Join Date: Feb 2005 Location: East Surrey Posts: 598	Re: BOV Gas Supply Have patience with this but how likely are GCS to fail when nothing is plugged into them? I'm half-heartedly thinking about putting a GCS into the manifold (which feeds both the ADV and the BOV) which would normally be unplugged. If I needed to bail then I would go OC, before plugging in the stage to go SCR at the first stop. Downsides are the faff factor and the additional failure point. The faff factor could be minimised by having a longish hose which is tucked neatly away (you're not going to have to restow it) but I can see the merits in keeping things as simple as possible. Janos __________________ You can lead a horse to water but you can't climb a ladder with a large bell in both hands - Vic Reeves www.hellfins.com/shed
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3rd April 2006, 22:03	#26 (permalink)
divetheworld Dive porn pimp Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Not Bought Yet Inspiration Classic Inspiration Vision Classic Kiss Other CCR Join Date: Mar 2005 Location: Leeds, England Posts: 1,586	Re: BOV Gas Supply Quote: (Originally Posted by Janos) Have patience with this but how likely are GCS to fail when nothing is plugged into them? I'm half-heartedly thinking about putting a GCS into the manifold (which feeds both the ADV and the BOV) which would normally be unplugged. If I needed to bail then I would go OC, before plugging in the stage to go SCR at the first stop. Downsides are the faff factor and the additional failure point. The faff factor could be minimised by having a longish hose which is tucked neatly away (you're not going to have to restow it) but I can see the merits in keeping things as simple as possible. Janos Just from my own experience, Popped one off to switch underwater and it did not seal. Stripped and put in the ultrasonic bath, perfect. Two months later when on the bench, popped it off, stuck again. The female on the stage has never failed, but is not connected unless bailing for (fun) practice. I concluded that the internal seal has a tendency to stick if it is not used and left connected. I'm happy to have them as they serve a good purpose but when I disconnect, I am prepared to shut down straight away, especially if that gas is depleted. Best, Brent. __________________ Attitude and self praise is no reccomendation. Dont try to be a great man, just be a man and let history be the judge of you. CHECK OUT OUR INTERWEBS FOR CUSTOM REBREATHER UPGRADES *WWW.NARKEDAT90.CO.UK* *http://www.grpservices.com/pursuit/* Supporting Shearwater Research Products in Europe
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