Orca - 1st dive completed!

kiwi_diver · 26th September 2007, 01:58

Well, it was only in the local pool, and to the giddy depth of 4 metres... but it was still a blast! Rebreathers ROCK!

I was loaded with EAN40 and had the flow rate set to about 10 LPM so it was sort of in the Draeger Dolphin operating envelope. At rest in 4m, the PPO2 settled at 0.46. After 5 minutes of finning around the pool, it had settled on 0.36. So my calcs say I was metabolising 1 LPM O2 at rest and 2 LPM O2 finning around which seems to be in the right sort of range.

My buddy, Dave, spotted a leak from the Surface Supply port cap, which needed tightening. A wrench sorted that out. Dave took the clam-shell cover off while we were down there and checked around my mod fittings and counterlung etc for leaks but they all seemed good.

My inflation/bail out reg mod worked a treat, though I didn't need much inflation in the pool, and good flow was available from the bail out reg.

I only had 130 bar in the first 3 litre cyl and that lasted nearly 45 minutes. Dave noticed that the lung was venting a bit with each expiration so it seems I can probably knock the flow rate back a bit.

Anyway, that was my first Rebreather dive and I was stoked to be using the Orca after only having had it a month.

A bonus was meeting Dave Ray at the pool. He built the Second Wind "Reefmaster" which can be seen here Photos Semiclosed Rebreathers
Dave was diving a little RGU-FM in the pool. I was amazed at how small they are...

Ray.

**Dave Sutton** · 26th September 2007, 16:25

Quote: (Originally Posted by kiwi_diver)

Dave noticed that the lung was venting a bit with each expiration so it seems I can probably knock the flow rate back a bit..

Actually, it means that it's *just right*. You definately need to have it vent on every exhalation in shallow water.

Glad the rig is working for you!

Dave

kiwi_diver · 26th September 2007, 23:23

Quote: (Originally Posted by Dave Sutton)

You definately need to have it vent on every exhalation in shallow water.

Thanks for confirming that Dave. Yesterday I watched some YouTube video of guys diving Dolphins in shallows and they were venting with every exhale too, so I was beginning to wonder if maybe that was OK.

Ray.

osiris · 27th September 2007, 11:02

God one mate! Lovely to watch I can tell you!

fatbob · 27th September 2007, 14:21

Hey, nice to see the old girl is still getting some use. I am assuming it is the only AKA60 in NZ. I had many hours of fun diving and tinkering with that rig. Hope you have a lot of fun with it mate.
If anyone in NZ is interested in an IDA72 I will be listing one on trademe in a couple of days, or PM me.

kiwidiver · 27th September 2007, 20:07

tony you can keep that ida 72 and I will take that mk 15 of your hands that is gathering dust in the corner if you like

kiwi_diver · 27th September 2007, 23:28

Hi Tony, thanks for the comments, nice to hear from an ex-owner.

What mix did you run in this rig and did you try different mixes and flow rates at all?

I've added a TecMe PPO2 meter for the time being. I have a 2 cell SCR/CCR eVodream unit on the way which I will use on it for open water dives. Also added a small manifold for inflation and bail-out reg.

Is your 72 converted at all?

Ray.

fatbob · 29th September 2007, 04:29

Gidday Ray.

From memory, I generally ran between 36 - 42% with flow rate between 8-11 lpm. Eventually I just left it set at 9 lpm and used 38-40% most of the time. I had a ppo2 meter and never got below .23 on strenuous surface swims.

Nice to see you got rid of that shabby tungum line to the ADV, I always meant to replace it, but it worked, so I never got around to it. I did all the stainless and alloy bumpers so that I could stand it upright in my boat without damaging the filler valve or having the scrubber bounce into the flow manifold.

I would like to have removed the valves to replace them or at least be able to clean the cylinders properly, but the brass on them is way too soft and they wouldnt budge without bending the valves, so I just left them in. The seals in the valves have been replaced with PTFE, which is quite soft so be sure not to over tighten them.

The 72 is non modified never used. I had planned to modify it to ccr, then bought an old MK15 which Mark quite rightly pointed out is sadly gathering dust. I just ran out of time, money and enthusiasm.
Well now I'm becoming enthused again, and still have no money, whence the sale of the 72.

Cheers, Tone.

kiwi_diver · 1st October 2007, 22:07

Thanks Tone, comforting to know that I am on the right track with mix and flow. Realy impressed with those stainless and alloy structural enhancements too, they make the clamshell much more rigid.

I tried to de-valve a cylinder last week and gave up before I broke something... Will have to remember to go easy on the PTFE seats when I turn off too, thanks for the warning.

Hope you manage to get back under soon, I hear the Port Kembla is a MK15 friendly wreck

Cheers, Ray.

Gilbert · 12th June 2008, 21:32

I guess I am month to late, but anyway.

I'have an AKA-60 too,and when I got it I wanted to be sure that the bottles were clean as I mix my nitrox myself, and was nervos when I first connected a 200bar 4x50 liter aircraft supply GOX battery on that russian thingy.
Could be a problem to explain why you have just blown the shelters roof of during lunch break...

For getting the valves out of the cylinders, I used a spanner first. After rounding the corners of the valve I discoverd it was brass. And that I have used the wrong tool :-) Damaged the surface really bad.

I got it out by putting the bottle in a lathe, and the flat sides of the valve I clamped down in the place where the latheknive should be normally.Also used some shims on the side of the valve so the thread had more distance on the side. Then I put a extensiontube over the lathekey that is used to clamp the bottle in the chuck, and turned it by hand. I guess it was about one meter long. Needed nearly the force that you apply when taking out a trucks tire bolts by hand. Steady force, not wacking on it with a hammer, no heating.

I was really nervous to break it, but I was glad I did it when I cleaned it out. One teaspoon of aluminium chips in each bottle. The amount and sort off, that was generated when this thread was tapped.

And the valve has no sinter filter...
It is a small brass tube with two holes in the sidewalls...

26th September 2007, 01:58	#1 (permalink)
kiwi_diver Alias - Ray Mansell Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Aug 2007 Location: Auckland, New Zealand Posts: 157	Orca - 1st dive completed! Well, it was only in the local pool, and to the giddy depth of 4 metres... but it was still a blast! Rebreathers ROCK! I was loaded with EAN40 and had the flow rate set to about 10 LPM so it was sort of in the Draeger Dolphin operating envelope. At rest in 4m, the PPO2 settled at 0.46. After 5 minutes of finning around the pool, it had settled on 0.36. So my calcs say I was metabolising 1 LPM O2 at rest and 2 LPM O2 finning around which seems to be in the right sort of range. My buddy, Dave, spotted a leak from the Surface Supply port cap, which needed tightening. A wrench sorted that out. Dave took the clam-shell cover off while we were down there and checked around my mod fittings and counterlung etc for leaks but they all seemed good. My inflation/bail out reg mod worked a treat, though I didn't need much inflation in the pool, and good flow was available from the bail out reg. I only had 130 bar in the first 3 litre cyl and that lasted nearly 45 minutes. Dave noticed that the lung was venting a bit with each expiration so it seems I can probably knock the flow rate back a bit. Anyway, that was my first Rebreather dive and I was stoked to be using the Orca after only having had it a month. A bonus was meeting Dave Ray at the pool. He built the Second Wind "Reefmaster" which can be seen here Photos Semiclosed Rebreathers Dave was diving a little RGU-FM in the pool. I was amazed at how small they are... Ray. __________________ Ray. == Latitude 36 South, where the deeper you dive, the warmer it gets! ==
(Offline)

26th September 2007, 16:25	#2 (permalink)
Dave Sutton Diveshop of Horrors Current Rebreather/s: Sport Kiss MK 15.X rEvo Other CCR Azimuth Home Build Other Rebreather/s: Evolution Megalodon rEvo Other CCR Azimuth Home Build Join Date: Jun 2006 Location: Narragansett, Rhode Island and Hackettstown, New Jersey Posts: 2,907	Re: Orca - 1st dive completed! Quote: (Originally Posted by kiwi_diver) Dave noticed that the lung was venting a bit with each expiration so it seems I can probably knock the flow rate back a bit.. Actually, it means that it's just right. You definately need to have it vent on every exhalation in shallow water. Glad the rig is working for you! Dave __________________ "Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com
(Offline)

26th September 2007, 23:23	#3 (permalink)
kiwi_diver Alias - Ray Mansell Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Aug 2007 Location: Auckland, New Zealand Posts: 157	Re: Orca - 1st dive completed! Quote: (Originally Posted by Dave Sutton) You definately need to have it vent on every exhalation in shallow water. Thanks for confirming that Dave. Yesterday I watched some YouTube video of guys diving Dolphins in shallows and they were venting with every exhale too, so I was beginning to wonder if maybe that was OK. Ray. __________________ Ray. == Latitude 36 South, where the deeper you dive, the warmer it gets! ==
(Offline)

27th September 2007, 11:02	#4 (permalink)
osiris RBW Member Current Rebreather/s: Inspiration Classic MK 15.X Other Rebreather/s: Sport Kiss Join Date: Feb 2006 Location: Auckland Posts: 346	Re: Orca - 1st dive completed! God one mate! Lovely to watch I can tell you!
(Online)

27th September 2007, 14:21	#5 (permalink)
fatbob New Member Current Rebreather/s: MK 15.X Other SCR Other Rebreather/s: Other SCR Join Date: Sep 2005 Location: New Zealand, Nelson Posts: 7	Re: Orca - 1st dive completed! Hey, nice to see the old girl is still getting some use. I am assuming it is the only AKA60 in NZ. I had many hours of fun diving and tinkering with that rig. Hope you have a lot of fun with it mate. If anyone in NZ is interested in an IDA72 I will be listing one on trademe in a couple of days, or PM me.
(Offline)

27th September 2007, 20:07	#6 (permalink)
kiwidiver RBW Member Current Rebreather/s: Inspiration Classic Inspiration Vision Azimuth Home Build Other Rebreather/s: Azimuth Home Build Join Date: Jul 2005 Location: new zealand Posts: 152	Re: Orca - 1st dive completed! tony you can keep that ida 72 and I will take that mk 15 of your hands that is gathering dust in the corner if you like
(Online)

27th September 2007, 23:28	#7 (permalink)
kiwi_diver Alias - Ray Mansell Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Aug 2007 Location: Auckland, New Zealand Posts: 157	Re: Orca - 1st dive completed! Hi Tony, thanks for the comments, nice to hear from an ex-owner. What mix did you run in this rig and did you try different mixes and flow rates at all? I've added a TecMe PPO2 meter for the time being. I have a 2 cell SCR/CCR eVodream unit on the way which I will use on it for open water dives. Also added a small manifold for inflation and bail-out reg. Is your 72 converted at all? Ray. __________________ Ray. == Latitude 36 South, where the deeper you dive, the warmer it gets! ==
(Offline)

29th September 2007, 04:29	#8 (permalink)
fatbob New Member Current Rebreather/s: MK 15.X Other SCR Other Rebreather/s: Other SCR Join Date: Sep 2005 Location: New Zealand, Nelson Posts: 7	Re: Orca - 1st dive completed! Gidday Ray. From memory, I generally ran between 36 - 42% with flow rate between 8-11 lpm. Eventually I just left it set at 9 lpm and used 38-40% most of the time. I had a ppo2 meter and never got below .23 on strenuous surface swims. Nice to see you got rid of that shabby tungum line to the ADV, I always meant to replace it, but it worked, so I never got around to it. I did all the stainless and alloy bumpers so that I could stand it upright in my boat without damaging the filler valve or having the scrubber bounce into the flow manifold. I would like to have removed the valves to replace them or at least be able to clean the cylinders properly, but the brass on them is way too soft and they wouldnt budge without bending the valves, so I just left them in. The seals in the valves have been replaced with PTFE, which is quite soft so be sure not to over tighten them. The 72 is non modified never used. I had planned to modify it to ccr, then bought an old MK15 which Mark quite rightly pointed out is sadly gathering dust. I just ran out of time, money and enthusiasm. Well now I'm becoming enthused again, and still have no money, whence the sale of the 72. Cheers, Tone.
(Offline)

1st October 2007, 22:07	#9 (permalink)
kiwi_diver Alias - Ray Mansell Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Aug 2007 Location: Auckland, New Zealand Posts: 157	Re: Orca - 1st dive completed! Thanks Tone, comforting to know that I am on the right track with mix and flow. Realy impressed with those stainless and alloy structural enhancements too, they make the clamshell much more rigid. I tried to de-valve a cylinder last week and gave up before I broke something... Will have to remember to go easy on the PTFE seats when I turn off too, thanks for the warning. Hope you manage to get back under soon, I hear the Port Kembla is a MK15 friendly wreck Cheers, Ray. __________________ Ray. == Latitude 36 South, where the deeper you dive, the warmer it gets! ==
(Offline)

12th June 2008, 21:32	#10 (permalink)
Gilbert New Member Current Rebreather/s: Other CCR Other SCR Other Rebreather/s: Other CCR Other SCR Join Date: Jun 2008 Location: Austria Posts: 5	Re: Orca - 1st dive completed! I guess I am month to late, but anyway. I'have an AKA-60 too,and when I got it I wanted to be sure that the bottles were clean as I mix my nitrox myself, and was nervos when I first connected a 200bar 4x50 liter aircraft supply GOX battery on that russian thingy. Could be a problem to explain why you have just blown the shelters roof of during lunch break... For getting the valves out of the cylinders, I used a spanner first. After rounding the corners of the valve I discoverd it was brass. And that I have used the wrong tool :-) Damaged the surface really bad. I got it out by putting the bottle in a lathe, and the flat sides of the valve I clamped down in the place where the latheknive should be normally.Also used some shims on the side of the valve so the thread had more distance on the side. Then I put a extensiontube over the lathekey that is used to clamp the bottle in the chuck, and turned it by hand. I guess it was about one meter long. Needed nearly the force that you apply when taking out a trucks tire bolts by hand. Steady force, not wacking on it with a hammer, no heating. I was really nervous to break it, but I was glad I did it when I cleaned it out. One teaspoon of aluminium chips in each bottle. The amount and sort off, that was generated when this thread was tapped. And the valve has no sinter filter... It is a small brass tube with two holes in the sidewalls...
(Offline)

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