Multiple Gases through a Dolphin

Sponge-Bob · 25th November 2006, 00:56

Hi,
Has anybody in the forum ever run their dolphin on a switch block and Aluminium side slings connecting all three jets to a gas, bottom (could be Trimix), travel and a deco gas?

I run such a system (not for a while due to ill health) and would be interested to hear from other divers running similar systems. I'm keen to get mine up and running again.

I run an 8 Litre bottle under the unit fitted with a Draeger cross valve to take a bail out reg on my bottom mix (Scubapro with a draeger style DIN). My side slings (7 Ltr) also have 'Y' valves on the bottles to take bail out regs. Everything runs through the switch block which is a real nice design and logical to use with different shapped valve knobs. The knobs run verticaly so obviously the bottom valve is bottom mix and the top valve deco. I have a 100% & 80% jets to choose from as well as the usual. I have been trying to get a larger wing for the unit. I hear Draeger did make one with greater lift.

The whole set up works well with the Aluminium bottles and lift isn't really an issue.

I have switched out the two litre bottle sack on the right of the unit and fitted a three litre. I work my pony bottle upside down and modified my hose lengths accordingly.

I once quite stupidly jumped in without the pony turned on. I swore never again and re-configured the set up. If your reg goes into freeflow or your LP inflator pops on your suit or wing you can easily control the situation manually.

I run an Oxy2 on the unit with an Air X O2, which needed a battery change, however Scubapro kindly informed me it was a bin job, so I upgraded to an Air Z O2.

I would be interested to hear from people running similar set ups or any after service mods. Its all good fun!

Stay safe....

bathtub · 25th November 2006, 07:41

sounds intresting, and a tidy set up... you got any photos we could take a look at (being cheeky!)
be great to see the routings and block...
Roy

Mikel-Deko · 25th November 2006, 09:24

Hi
I used to dive a Dolphin with, trimix in a 7 alu tank throu the 32% jet, and O2 throu 100%.
I used to open the O2 tank in the 1st deep stop and let it open controling with de Oxy2 the ppO2. That way, you are always breathing trimix with a highter % of O2. In the 6 mtrs stop, it is a little dificult to fill the lungs just with O2 because you don't have a ADV but it is a good system.

After a few dives that way, i decided that i was pushing to much the limits of the Dolphin and i bought a Inspi.

Regards

Mikel

bletso · 25th November 2006, 13:34

I started that way and didn't find it very friendly, so I went complete CCR, much better way to appraoch the problem. I can switch gases on the fly from off-board.

Dale

gibbogeo · 27th November 2006, 19:30

Quote: (Originally Posted by Sponge-Bob)

Hi,
Has anybody in the forum ever run their dolphin on a switch block and Aluminium side slings connecting all three jets to a gas, bottom (could be Trimix), travel and a deco gas?

I did it for a while with thre oxigen monitor.

Then i considered that it was non worth to continue in this way, i bought a ds4, a kiss valve, the swagelok parts and converted my kiss to CCR.

I believe that as soon you depend from electronic to check what you are breathing, it is no worth _not_ to go to CCR.

Sponge-Bob · 28th November 2006, 23:38

Quote: (Originally Posted by bathtub)

sounds intresting, and a tidy set up... you got any photos we could take a look at (being cheeky!)
be great to see the routings and block...
Roy

Hi,
Sorry it took so long to get back. I will take some pics and try and get them posted this weekend.

I'm very interested to see what can be done with the Dolphin, mods etc.

I've done CCR and owned an Inspiration back in 2000. The unit was new and failed on me (handsets went blank, started re-calibrating), I didn't trust it so I sold it. I lost confidence in the unit.

I'm a big Dolphin fan due to its simplicity and would like to hear more from the semi closed fraternity.

Keep it safe!

RonMicjan · 29th November 2006, 02:07

screw the SCR, close the loop : ) anything else is a waste of time and helium.

http://www.tmishop.comfor all the details, pics and plumbing.

Sponge-Bob · 29th November 2006, 18:28

Quote: (Originally Posted by bathtub)

sounds intresting, and a tidy set up... you got any photos we could take a look at (being cheeky!)
be great to see the routings and block...
Roy

Hi,
I have not had time to get the unit assembled but here is the switch block showing the Scubapro quick connectors which are easy to work with under water due to their size if you ever need to cross patch. Also the three custom jet connectors and the bypass valve connector.

Scubapro hoses connect everything together.

'Y' valve on stages and primary cylinder.

Over the next few weeks I will get the unit assembled.

No more CCR comments please! We all know its the way to go! But tinkering with a Draeger has the same feel as customising a beat up old Escort MK1 to get 150mph out of it!

Come on guys.... Lets 'pimp' this Drager!

CCR is so predictable (or not depending on the model you own

)

Keep it safe!

**Freef** · 1st December 2006, 20:42

Do you have a flow rate for the 80% jet? I'd be interested to see what it is.

Is 100% really the way to go though? 80% is more in favour amongst the trimix divers I OC with as you can get on it deeper and have slightly less O2 time after you surface...and it is easier to get a 232 bar 80% fil than 100%.

If you plumb 100% through any of the jets it will eventually work up to 100% in the loop. With the bypass, why not run it from the bottom mix so yo gan always get gas if you need to? Or better still, if someone could make a 'T' piece that lets you plug two drager hoses into one jet [John Routley, are you paying attention???] you could run both 100% and your bottom mix into one jet and also have your deco mix work the bypass valve.

When I deco on OC I turn the loop off.

Sponge-Bob · 2nd December 2006, 00:01

Hi Freef,
Thanks for the input.

I've been medically unfit to dive since 2002. I cleaned and stripped down all my gear packed it away. Its taking me a while to get my head around things again.

I've got so much stuff all packed away all over the place that its taking a while to find parts.

I got the Dolphin out tonight and cleaned it and tested the flow through the jets. Everything is working spot on. I need to check the intermediate pressure in the first stage yet, just in case its off.

The guys from Draeger gave me two jets as mentioned. One 100% & one 80% but they also gave me a simple flow gauge marked 80% & 100% which doesn't give a flow rate, it just confirms that the jet is OK. I'll do a manual check and get back to you.

I've got two Draeger prototype (or were 5 years ago) first stages, one for each stage. With the 'Y' valves you can obviously go OC on deco if needed. I'll post some pics tomorrow.

Whats bugging me is this port in the valve (between the black & blue valve knobs) I can't for the life of me remember what is was for. At first I thought bypass, its cross drilled but I don't seem to be able to blow through it manually. I don't remenber using it but if I didn't I would have assumed it would be plugged.

Soon as the weather improves I'm going to get out and dive the standard unit them piece all these mods together.

I found your previous post very informative ( Semi Closed Rebreather diving gas calculations. ) and value your imput.

25th November 2006, 00:56	#1 (permalink)
Sponge-Bob New Member Current Rebreather/s: Inspiration Classic Other CCR Dolphin Ray Other Rebreather/s: Other CCR Dolphin Ray Join Date: Nov 2006 Location: Scotland Posts: 29	Multiple Gases through a Dolphin Hi, Has anybody in the forum ever run their dolphin on a switch block and Aluminium side slings connecting all three jets to a gas, bottom (could be Trimix), travel and a deco gas? I run such a system (not for a while due to ill health) and would be interested to hear from other divers running similar systems. I'm keen to get mine up and running again. I run an 8 Litre bottle under the unit fitted with a Draeger cross valve to take a bail out reg on my bottom mix (Scubapro with a draeger style DIN). My side slings (7 Ltr) also have 'Y' valves on the bottles to take bail out regs. Everything runs through the switch block which is a real nice design and logical to use with different shapped valve knobs. The knobs run verticaly so obviously the bottom valve is bottom mix and the top valve deco. I have a 100% & 80% jets to choose from as well as the usual. I have been trying to get a larger wing for the unit. I hear Draeger did make one with greater lift. The whole set up works well with the Aluminium bottles and lift isn't really an issue. I have switched out the two litre bottle sack on the right of the unit and fitted a three litre. I work my pony bottle upside down and modified my hose lengths accordingly. I once quite stupidly jumped in without the pony turned on. I swore never again and re-configured the set up. If your reg goes into freeflow or your LP inflator pops on your suit or wing you can easily control the situation manually. I run an Oxy2 on the unit with an Air X O2, which needed a battery change, however Scubapro kindly informed me it was a bin job, so I upgraded to an Air Z O2. I would be interested to hear from people running similar set ups or any after service mods. Its all good fun! Stay safe.... __________________ If you want a Guarantee.....Buy a toaster!
(Offline)

25th November 2006, 07:41	#2 (permalink)
bathtub What bubbles? - DOH ! Current Rebreather/s: Dolphin Other Rebreather/s: Dolphin Join Date: Oct 2006 Location: Switzerland, Zug Posts: 35	Re: Multiple Gases through a Dolphin sounds intresting, and a tidy set up... you got any photos we could take a look at (being cheeky!) be great to see the routings and block... Roy
(Offline)

25th November 2006, 09:24	#3 (permalink)
Mikel-Deko RBW Member Current Rebreather/s: Inspiration Classic Other CCR Other Rebreather/s: Other CCR Join Date: Jul 2005 Location: Basque Country -Sp- Posts: 476	Re: Multiple Gases through a Dolphin Hi I used to dive a Dolphin with, trimix in a 7 alu tank throu the 32% jet, and O2 throu 100%. I used to open the O2 tank in the 1st deep stop and let it open controling with de Oxy2 the ppO2. That way, you are always breathing trimix with a highter % of O2. In the 6 mtrs stop, it is a little dificult to fill the lungs just with O2 because you don't have a ADV but it is a good system. After a few dives that way, i decided that i was pushing to much the limits of the Dolphin and i bought a Inspi. Regards Mikel
(Offline)

25th November 2006, 13:34	#4 (permalink)
bletso An independent diver. Current Rebreather/s: Dolphin Home Build Other Rebreather/s: Dolphin Home Build Join Date: May 2006 Location: Louisville, KY, USA Posts: 263	Re: Multiple Gases through a Dolphin I started that way and didn't find it very friendly, so I went complete CCR, much better way to appraoch the problem. I can switch gases on the fly from off-board. Dale
(Offline)

27th November 2006, 19:30	#5 (permalink)
gibbogeo Gilberto Bonaga, Italy Current Rebreather/s: Classic Kiss Dolphin Home Build Other Rebreather/s: Dolphin Home Build Join Date: Sep 2005 Location: italy Posts: 332	Re: Multiple Gases through a Dolphin Quote: (Originally Posted by Sponge-Bob) Hi, Has anybody in the forum ever run their dolphin on a switch block and Aluminium side slings connecting all three jets to a gas, bottom (could be Trimix), travel and a deco gas? I did it for a while with thre oxigen monitor. Then i considered that it was non worth to continue in this way, i bought a ds4, a kiss valve, the swagelok parts and converted my kiss to CCR. I believe that as soon you depend from electronic to check what you are breathing, it is no worth _not_ to go to CCR.
(Offline)

28th November 2006, 23:38	#6 (permalink)
Sponge-Bob New Member Current Rebreather/s: Inspiration Classic Other CCR Dolphin Ray Other Rebreather/s: Other CCR Dolphin Ray Join Date: Nov 2006 Location: Scotland Posts: 29	Re: Multiple Gases through a Dolphin Quote: (Originally Posted by bathtub) sounds intresting, and a tidy set up... you got any photos we could take a look at (being cheeky!) be great to see the routings and block... Roy Hi, Sorry it took so long to get back. I will take some pics and try and get them posted this weekend. I'm very interested to see what can be done with the Dolphin, mods etc. I've done CCR and owned an Inspiration back in 2000. The unit was new and failed on me (handsets went blank, started re-calibrating), I didn't trust it so I sold it. I lost confidence in the unit. I'm a big Dolphin fan due to its simplicity and would like to hear more from the semi closed fraternity. Keep it safe! __________________ If you want a Guarantee.....Buy a toaster!
(Offline)

29th November 2006, 02:07	#7 (permalink)
RonMicjan Cap Ron scourge of the NW Current Rebreather/s: Megalodon Dolphin Home Build Other Rebreather/s: Sport Kiss Classic Kiss Dolphin Home Build Join Date: Feb 2005 Location: Cape Disapointment, The Graveyard of the Pacific Posts: 1,119	Re: Multiple Gases through a Dolphin screw the SCR, close the loop : ) anything else is a waste of time and helium. http://www.tmishop.comfor all the details, pics and plumbing. __________________ Marine rescue, towing and salvage. Interfering with natural selection since 1983. www.tmishop.com Diving bits etc. www.seatowpdx.com The Summer Job
(Offline)

1st December 2006, 20:42	#9 (permalink)
Freef Custom Title Disallowed! Current Rebreather/s: Dolphin Other Rebreather/s: Dolphin Join Date: Jan 2006 Location: Land of the Freef, UK. Posts: 1,424	Re: Multiple Gases through a Dolphin Do you have a flow rate for the 80% jet? I'd be interested to see what it is. Is 100% really the way to go though? 80% is more in favour amongst the trimix divers I OC with as you can get on it deeper and have slightly less O2 time after you surface...and it is easier to get a 232 bar 80% fil than 100%. If you plumb 100% through any of the jets it will eventually work up to 100% in the loop. With the bypass, why not run it from the bottom mix so yo gan always get gas if you need to? Or better still, if someone could make a 'T' piece that lets you plug two drager hoses into one jet [John Routley, are you paying attention???] you could run both 100% and your bottom mix into one jet and also have your deco mix work the bypass valve. When I deco on OC I turn the loop off. __________________ David. Diving the mahogany rebreather.
(Offline)

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