First pool dive on homebuilt rebreather

marekm · 22nd February 2007, 12:47

Hi everyone,

My rebreather project has advanced to the stage of O2 mCCR so I took it to the local pool for its first test dive and my first dive on a rebreather.

http://home.iprimus.com.au/marekm/rb...t/sideview.jpg
http://home.iprimus.com.au/marekm/rb...st/deepend.jpg
See more photos here:

New Page 1

To my complete amazement the unit worked and diving it was far easier to dive than I expected.

Things I noted about the rebreather:
1. The parts of the unit seem to snap into place when underwater and are not the awkward jumble of tubes and hoses they are on the surface.
2. Weight of breathing was negligable, about the same as a R190 reg.
3. The counterlungs were of ample size underwater, even though on the surface they feel too small.
4. Buoyancy control is fantastic compared to OC scuba. Being able to breathe in and out for a while without changing depth is quite amazing.
5. The unit is very quiet when breathing and indeed produces no bubbles

6. A 30min pool dive used up a tiny 20bar of O2 from a 2.5L tank.

The experience of diving a rebreather the first time has left a lasting positive impression on me. Furhtermore, it has left me in no doubt that this is the way I want to go in my diving.

Feel free to leave any comments/questions/criticisms you may have.

Cheers.
-Marek

sven · 22nd February 2007, 14:38

Marek,

Conratulations! Apart from the length of the hoses, everything else looks pretty good! I look forward to a write-up here on RBW

jaap · 22nd February 2007, 14:49

Nice!

May I ask what sort of breathing hoses you use?

1 kg scrubber is too small if you want to take it further than a O2-Rebreather. Do you plan on redoing the scrubber to make a bigger one and maybe with in/out connectors on the top?

A simple thing that would make it more streamline would be to put an elbow on the bottom of the scrubber and run a smooth tube/or hose up the length of the scrubber in between it and the air tank against you back.

Are the lungs MSR-bags?

marekm · 22nd February 2007, 15:20

Hi Guys,

Thankyou for your comments and for taking the time to look at my effort. In regards to your questions:

Sven:
I worked out that all the loop hoses were too long after taking it for a dive and looking at the photos. They will indeed be shortened a bit at a time over the next few dives. I simply decided to make them longer than necessary so I can shorten them rather than the other way around. As for a RBW write up, that will have to wait a for quite some time while I 'perfect' the unit

jaap:
Glad you asked about the hoses. I have tried many different hoses for the DSV and found them to be either too stiff, or too soft and collapsible. I looked at the KISS and Inspiration hoses, but was not happy with them either. After going through several hose and ducting warehouses, I found a company called Toney Powell Hose & Fittings and that sold the hoses I was after. The DSV hose is a 38mm ID steel wire reinforced plasticiser free PVC ducting tube. The steel wire inside is sealed within the plastic so it does not corrode (also I heat sealed the PVC at the end of the hoses where I cut them). This hose is ultra flexible (turn radius is ~6cm, stretches up to ~30%) while at the same time uncollapsible and abrasion resistant. The only down side is that the steel wire inside can be irreversibly crushed with a heavy object (like an AL80). The T-piece to scrubber hoses are vacuum cleaner hoses with 32mm ID (mainly because I want to conserve my limited supply of the 38mm Tony Powell hoses).

As you surmised, I have a 150mm diameter radial ~3kg scrubber housing (with in and out on top) in the works for deeper work. Also, I have considered the Inspo-like smooth return tube from the bottom of the scrubber, but decided to heat reshape the vacuum cleaner hose so it has a bend it the bottom instead. This is because it uses less parts and makes it easier to handle the scrubber when repacking. Also, I can't run the return hose between the BP and tanks since the diluent SPG/LP hoses are running through there (See here http://home.iprimus.com.au/marekm/rb/100_0551.jpg)

The counterlungs are infact two 2L MSR bags matched against my 3.5L lung volume. On the surface (with the loop hoses and t-pieces laying on them) they seem to be too small for a full breath, but underwater the are more than large enough.

Again, thankyou for you input, and stay tuned for further developments.
-Marek

Ekke · 22nd February 2007, 15:26

Nice-looking project! Hope you can get oxygen control to it and make it go deeper..

We also have DIY rebreather project and I hope it will see daylight.. err.. poolwater in next month or so..

(Winter here in Finland is still pretty dark and days are short.. And maybe little cold, now there is only -20'C outside

)

**Dave Sutton** · 22nd February 2007, 15:47

Well done. Gets the "Diver Dave Sutton Seal of Approval" and "Best First Attempt from Oz for 2007" awards...

Now... KISS that 02 supply, use the air bottle to feed the loop, add another cell and you'll be on the next track!

Enjoy it for 100 hours on pure 02 though. You did a nice job.

Dave

Tom Rose · 22nd February 2007, 16:03

Quote: (Originally Posted by marekm)

Hi everyone,

My rebreather project has advanced to the stage of O2 mCCR so I took it to the local pool for its first test dive and my first dive on a rebreather.

http://home.iprimus.com.au/marekm/rb...t/sideview.jpg
http://home.iprimus.com.au/marekm/rb...st/deepend.jpg
See more photos here:

New Page 1

To my complete amazement the unit worked and diving it was far easier to dive than I expected.

Things I noted about the rebreather:
1. The parts of the unit seem to snap into place when underwater and are not the awkward jumble of tubes and hoses they are on the surface.
2. Weight of breathing was negligable, about the same as a R190 reg.
3. The counterlungs were of ample size underwater, even though on the surface they feel too small.
4. Buoyancy control is fantastic compared to OC scuba. Being able to breathe in and out for a while without changing depth is quite amazing.
5. The unit is very quiet when breathing and indeed produces no bubbles

6. A 30min pool dive used up a tiny 20bar of O2 from a 2.5L tank.

The experience of diving a rebreather the first time has left a lasting positive impression on me. Furhtermore, it has left me in no doubt that this is the way I want to go in my diving.

Feel free to leave any comments/questions/criticisms you may have.

Cheers.
-Marek

Very nice job,

You can have a lot of fun with that unit.

I noticed that you have already been advised that your scrubber is too small. Maybe not...you should get a couple of hours with it in warm water easily. Bringing a smooth tube up from the bottom will work but perhaps is not necessary if you current hoses do not flop around.

IMHO your next step is to practice manual oxygen addition staying just off the bottom of the pool. Get used to the unit....learn its little flaws....

Then try performing some tasks like taking pictures assembling things...doing a rubic cube....while using it....light task loading.....

After you are fully comfortable with manual addition....add a O2 supply with a leaky orifice...then repeat the task loading exercises.....

Try using smaller tanks to lose some of the weight....if they are available...I use one liter tanks when I can for dives up to two hours down to about 100 feet max. In full CCr mode.

By the end of that process you will have probably changed the configuration a number of times to work better (for you).

Most of all....enjoy your creation.....in the eyes of all of us home builders....its a beauty...congratulations.

Tom Rose

marekm · 22nd February 2007, 16:27

Quote: (Originally Posted by Dave Sutton)

Well done. Gets the "Diver Dave Sutton Seal of Approval" and "Best First Attempt from Oz for 2007" awards...

Dave

Hahaha. Thanks Dave, but you deserve a fair bit of credit as I basically used your website as an encylopedia of DIY rebreather construction.

Quote: (Originally Posted by Dave Sutton)

Now... KISS that 02 supply, use the air bottle to feed the loop, add another cell and you'll be on the next track!

Enjoy it for 100 hours on pure 02 though. You did a nice job.

Dave

You read my mind Dave, all those things are in the pipeline and will be put into action over the coming months. However, I still like to test the rig incrementally as I go through the build process to check that the system works, and fix any problems that come up before moving on and increasing complexity.

However, I'm not going to go down the KISS route, but install some McMaster Carr CMF orifices/filters instead (as soon as Denzel gets his and tests them out, hint hint

). Also, I'm working on the 4th generation PO2 meters that have lacquer coated PCBs and use oil filled housings.

But for now, after 5 months of building, I'm itching to get some pure O2 Rebreather diving done so I can get some more in water experience.

Cheers.
-Marek

marekm · 22nd February 2007, 17:04

Hi Tom,

As with Dave, you deserve some the credit for this build, as I studied your website inside and out when thinking about how to design and build the unit. And if the smile on my face following todays pool session is anything to go by, you certainly can have alot of fun with such units

.

I've done a 'couch dive' (ie: walking up and down a flight of stairs) on the 1kg scrubber and it lasted 90minutes without breakthrough before I got tired of walking around with 20kg+ of rebreather on my back. Thus I'm guessing it will max out at 2 hours in warm water (which is more than enough for me while I'm still learning to dive the rig).

I've noticed some of the effects metabolising oxygen has on buoyancy, but I'm sure there is more to learn. In addition, I've started some basic taskloading skills like removing and replacing my mask underwater, taking photographs, but I don't know about the rubics cube, I have trouble with that on the surface hehe

but seriously, thankyou for the sequence of excercise to go through while developing the unit.

In terms of tanks, in addition to the 2.5L tanks pictured, I have a pair of light weight 0.5L tanks (good for ~1 hour) that I can use for training purposes. I just went with the two 2.5L as they were what I had and I expected to waste alot gas while learning to use the rig.

As for changing the rig with time, tinkering with it is half the fun of homebuild rebreather diving (at least for me). Infact, I don't think I own a single piece of diver gear I haven't built or modified in some way.

Once again, thankyou for your advice.

PS: Does CEDU's Robert Ianello come by this forum? As his website also played a key role in inspiring me to build the rebreather.

**Dave Sutton** · 22nd February 2007, 17:12

Quote: (Originally Posted by marekm)

However, I'm not going to go down the KISS route, but install some McMaster Carr CMF orifices/filters instead (as soon as Denzel gets his and tests them out, hint hint

).

Yup... they are sitting on my bench... and I'm in a hotel 1000 miles away. Maybe one day I will be reunited with my home....

Rose, Ianello, myself... you seem to have hit up the homebrew trifecta. At least *two* of us are Florida Tech grads... but Bob and I still talk to Tom anyhow.....

Tom, Doria Trip is coming... C02 monitor for the rig?

Best,

Dave

22nd February 2007, 12:47	#1 (permalink)
marekm Banned Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Oct 2006 Location: Brisbane, Australia Posts: 196	My first pool dive on homebuilt rebreather Hi everyone, My rebreather project has advanced to the stage of O2 mCCR so I took it to the local pool for its first test dive and my first dive on a rebreather. http://home.iprimus.com.au/marekm/rb...t/sideview.jpg http://home.iprimus.com.au/marekm/rb...st/deepend.jpg See more photos here: New Page 1 To my complete amazement the unit worked and diving it was far easier to dive than I expected. Things I noted about the rebreather: 1. The parts of the unit seem to snap into place when underwater and are not the awkward jumble of tubes and hoses they are on the surface. 2. Weight of breathing was negligable, about the same as a R190 reg. 3. The counterlungs were of ample size underwater, even though on the surface they feel too small. 4. Buoyancy control is fantastic compared to OC scuba. Being able to breathe in and out for a while without changing depth is quite amazing. 5. The unit is very quiet when breathing and indeed produces no bubbles 6. A 30min pool dive used up a tiny 20bar of O2 from a 2.5L tank. The experience of diving a rebreather the first time has left a lasting positive impression on me. Furhtermore, it has left me in no doubt that this is the way I want to go in my diving. Feel free to leave any comments/questions/criticisms you may have. Cheers. -Marek Last edited by marekm : 22nd February 2007 at 13:39. Reason: Added the photos
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22nd February 2007, 14:38	#2 (permalink)
sven Blogs Admin / Forum Mod Current Rebreather/s: Inspiration Classic Other Rebreather/s: Evolution Join Date: Nov 2005 Location: Sydney Posts: 551	Re: My first pool dive on homebuilt rebreather Marek, Conratulations! Apart from the length of the hoses, everything else looks pretty good! I look forward to a write-up here on RBW __________________ Regards, Sven The Sydney Project website: http://www.sydneyproject.com My Blog: http://sven.rebreatherworld.com "Whenever you find yourself on the side of the majority, it's time to pause and reflect." Mark Twain
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22nd February 2007, 14:49	#3 (permalink)
jaap Normal people worry me Current Rebreather/s: Classic Kiss Other CCR RB80 / Clone Ray Other SCR Home Build Other Rebreather/s: Other CCR RB80 / Clone Ray Other SCR Home Build Join Date: Jun 2005 Location: Stockholm Sweden Posts: 473	Re: First pool dive on homebuilt rebreather Nice! May I ask what sort of breathing hoses you use? 1 kg scrubber is too small if you want to take it further than a O2-Rebreather. Do you plan on redoing the scrubber to make a bigger one and maybe with in/out connectors on the top? A simple thing that would make it more streamline would be to put an elbow on the bottom of the scrubber and run a smooth tube/or hose up the length of the scrubber in between it and the air tank against you back. Are the lungs MSR-bags? __________________ My initials: JAAP
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22nd February 2007, 15:20	#4 (permalink)
marekm Banned Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Oct 2006 Location: Brisbane, Australia Posts: 196	Re: First pool dive on homebuilt rebreather Hi Guys, Thankyou for your comments and for taking the time to look at my effort. In regards to your questions: Sven: I worked out that all the loop hoses were too long after taking it for a dive and looking at the photos. They will indeed be shortened a bit at a time over the next few dives. I simply decided to make them longer than necessary so I can shorten them rather than the other way around. As for a RBW write up, that will have to wait a for quite some time while I 'perfect' the unit jaap: Glad you asked about the hoses. I have tried many different hoses for the DSV and found them to be either too stiff, or too soft and collapsible. I looked at the KISS and Inspiration hoses, but was not happy with them either. After going through several hose and ducting warehouses, I found a company called Toney Powell Hose & Fittings and that sold the hoses I was after. The DSV hose is a 38mm ID steel wire reinforced plasticiser free PVC ducting tube. The steel wire inside is sealed within the plastic so it does not corrode (also I heat sealed the PVC at the end of the hoses where I cut them). This hose is ultra flexible (turn radius is ~6cm, stretches up to ~30%) while at the same time uncollapsible and abrasion resistant. The only down side is that the steel wire inside can be irreversibly crushed with a heavy object (like an AL80). The T-piece to scrubber hoses are vacuum cleaner hoses with 32mm ID (mainly because I want to conserve my limited supply of the 38mm Tony Powell hoses). As you surmised, I have a 150mm diameter radial ~3kg scrubber housing (with in and out on top) in the works for deeper work. Also, I have considered the Inspo-like smooth return tube from the bottom of the scrubber, but decided to heat reshape the vacuum cleaner hose so it has a bend it the bottom instead. This is because it uses less parts and makes it easier to handle the scrubber when repacking. Also, I can't run the return hose between the BP and tanks since the diluent SPG/LP hoses are running through there (See here http://home.iprimus.com.au/marekm/rb/100_0551.jpg) The counterlungs are infact two 2L MSR bags matched against my 3.5L lung volume. On the surface (with the loop hoses and t-pieces laying on them) they seem to be too small for a full breath, but underwater the are more than large enough. Again, thankyou for you input, and stay tuned for further developments. -Marek
(Offline)

22nd February 2007, 15:26	#5 (permalink)
Ekke New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Oct 2005 Location: Oulu, Finland Posts: 23	Re: First pool dive on homebuilt rebreather Nice-looking project! Hope you can get oxygen control to it and make it go deeper.. We also have DIY rebreather project and I hope it will see daylight.. err.. poolwater in next month or so.. (Winter here in Finland is still pretty dark and days are short.. And maybe little cold, now there is only -20'C outside )
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22nd February 2007, 15:47	#6 (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: First pool dive on homebuilt rebreather Well done. Gets the "Diver Dave Sutton Seal of Approval" and "Best First Attempt from Oz for 2007" awards... Now... KISS that 02 supply, use the air bottle to feed the loop, add another cell and you'll be on the next track! Enjoy it for 100 hours on pure 02 though. You did a nice job. Dave __________________ "Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com
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22nd February 2007, 16:03	#7 (permalink)
Tom Rose Still Learning Current Rebreather/s: Other CCR Home Build Other Rebreather/s: Prism Topaz Other CCR Home Build Join Date: Oct 2005 Location: USA,North Carolina Posts: 331	Re: My first pool dive on homebuilt rebreather Quote: (Originally Posted by marekm) Hi everyone, My rebreather project has advanced to the stage of O2 mCCR so I took it to the local pool for its first test dive and my first dive on a rebreather. http://home.iprimus.com.au/marekm/rb...t/sideview.jpg http://home.iprimus.com.au/marekm/rb...st/deepend.jpg See more photos here: New Page 1 To my complete amazement the unit worked and diving it was far easier to dive than I expected. Things I noted about the rebreather: 1. The parts of the unit seem to snap into place when underwater and are not the awkward jumble of tubes and hoses they are on the surface. 2. Weight of breathing was negligable, about the same as a R190 reg. 3. The counterlungs were of ample size underwater, even though on the surface they feel too small. 4. Buoyancy control is fantastic compared to OC scuba. Being able to breathe in and out for a while without changing depth is quite amazing. 5. The unit is very quiet when breathing and indeed produces no bubbles 6. A 30min pool dive used up a tiny 20bar of O2 from a 2.5L tank. The experience of diving a rebreather the first time has left a lasting positive impression on me. Furhtermore, it has left me in no doubt that this is the way I want to go in my diving. Feel free to leave any comments/questions/criticisms you may have. Cheers. -Marek Very nice job, You can have a lot of fun with that unit. I noticed that you have already been advised that your scrubber is too small. Maybe not...you should get a couple of hours with it in warm water easily. Bringing a smooth tube up from the bottom will work but perhaps is not necessary if you current hoses do not flop around. IMHO your next step is to practice manual oxygen addition staying just off the bottom of the pool. Get used to the unit....learn its little flaws.... Then try performing some tasks like taking pictures assembling things...doing a rubic cube....while using it....light task loading..... After you are fully comfortable with manual addition....add a O2 supply with a leaky orifice...then repeat the task loading exercises..... Try using smaller tanks to lose some of the weight....if they are available...I use one liter tanks when I can for dives up to two hours down to about 100 feet max. In full CCr mode. By the end of that process you will have probably changed the configuration a number of times to work better (for you). Most of all....enjoy your creation.....in the eyes of all of us home builders....its a beauty...congratulations. Tom Rose __________________ The 50-50-90 rule: Anytime I have a 50-50 chance of getting something right, there's a 90% probability I'll get it wrong the first time. www.atlimp.com
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22nd February 2007, 16:27	#8 (permalink)
marekm Banned Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Oct 2006 Location: Brisbane, Australia Posts: 196	Re: First pool dive on homebuilt rebreather Quote: (Originally Posted by Dave Sutton) Well done. Gets the "Diver Dave Sutton Seal of Approval" and "Best First Attempt from Oz for 2007" awards... Dave Hahaha. Thanks Dave, but you deserve a fair bit of credit as I basically used your website as an encylopedia of DIY rebreather construction. Quote: (Originally Posted by Dave Sutton) Now... KISS that 02 supply, use the air bottle to feed the loop, add another cell and you'll be on the next track! Enjoy it for 100 hours on pure 02 though. You did a nice job. Dave You read my mind Dave, all those things are in the pipeline and will be put into action over the coming months. However, I still like to test the rig incrementally as I go through the build process to check that the system works, and fix any problems that come up before moving on and increasing complexity. However, I'm not going to go down the KISS route, but install some McMaster Carr CMF orifices/filters instead (as soon as Denzel gets his and tests them out, hint hint ). Also, I'm working on the 4th generation PO2 meters that have lacquer coated PCBs and use oil filled housings. But for now, after 5 months of building, I'm itching to get some pure O2 Rebreather diving done so I can get some more in water experience. Cheers. -Marek
(Offline)

22nd February 2007, 17:04	#9 (permalink)
marekm Banned Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Oct 2006 Location: Brisbane, Australia Posts: 196	Re: My first pool dive on homebuilt rebreather Hi Tom, As with Dave, you deserve some the credit for this build, as I studied your website inside and out when thinking about how to design and build the unit. And if the smile on my face following todays pool session is anything to go by, you certainly can have alot of fun with such units . I've done a 'couch dive' (ie: walking up and down a flight of stairs) on the 1kg scrubber and it lasted 90minutes without breakthrough before I got tired of walking around with 20kg+ of rebreather on my back. Thus I'm guessing it will max out at 2 hours in warm water (which is more than enough for me while I'm still learning to dive the rig). I've noticed some of the effects metabolising oxygen has on buoyancy, but I'm sure there is more to learn. In addition, I've started some basic taskloading skills like removing and replacing my mask underwater, taking photographs, but I don't know about the rubics cube, I have trouble with that on the surface hehe but seriously, thankyou for the sequence of excercise to go through while developing the unit. In terms of tanks, in addition to the 2.5L tanks pictured, I have a pair of light weight 0.5L tanks (good for ~1 hour) that I can use for training purposes. I just went with the two 2.5L as they were what I had and I expected to waste alot gas while learning to use the rig. As for changing the rig with time, tinkering with it is half the fun of homebuild rebreather diving (at least for me). Infact, I don't think I own a single piece of diver gear I haven't built or modified in some way. Once again, thankyou for your advice. PS: Does CEDU's Robert Ianello come by this forum? As his website also played a key role in inspiring me to build the rebreather.
(Offline)

22nd February 2007, 17:12	#10 (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: First pool dive on homebuilt rebreather Quote: (Originally Posted by marekm) However, I'm not going to go down the KISS route, but install some McMaster Carr CMF orifices/filters instead (as soon as Denzel gets his and tests them out, hint hint ). Yup... they are sitting on my bench... and I'm in a hotel 1000 miles away. Maybe one day I will be reunited with my home.... Rose, Ianello, myself... you seem to have hit up the homebrew trifecta. At least two of us are Florida Tech grads... but Bob and I still talk to Tom anyhow..... Tom, Doria Trip is coming... C02 monitor for the rig? Best, Dave __________________ "Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com Last edited by Dave Sutton : 22nd February 2007 at 17:15.
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