First pool dive on homebuilt rebreather

Tom Rose · 22nd February 2007, 19:38

Quote: (Originally Posted by Dave Sutton)

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?

I will simply ignore the kindly Florida Tech comment......I barely got out of College since I went to a hard one.

The CO2 monitor is on schedule.....glad I gave myself a little extra time so I would not catch a bunch of grief for not delivering...

I was using a McMaster Carr orifice with filter three weeks ago in Bonaire...it worked great on the Cressi Rig that I so love due to its low weigh and ease of operation and setup.

Just see the smile on my face in the first shot...

I have about 50 hours on that configuration and have really been happy. I am going to do a little hose configuration changes, but that is minor. I do suggest that you carry an extra orifice with you....cheap insurance....

Here is the configuration for my Cressi rig...Remember that the Oxygen tank hangs below the Counter lung. This makes the toggle valve almost where it was designed to be. I can find it with my left hand in seconds.

1. Pressure gauge LDS
2. Over pressure valve LDS
3. LP to 1/4 npt fitting one for toggle valve one for orifice side LDS
4. Oxygen toggle valve Swagelock Local supplier Raleigh Valve and Fitting
5. Orifice protection filter McMaster Carr
6. Orifice McMaster Carr
7. Push on fittings local supplier Motion Industries also McMaster Carr
8. Oxygen feed consolidator local supplier Motion Industries also McMaster Carr

The brass piece is a 1/4 npt female coupling that I have not nickel plated yet.

All hooked up to a compensated off the shelf oxygen cleaned din regulator ordered from LDS. Not an expensive one as you can easily see.

As I have reported earlier for depths to about 100 feet, this works fine.

I use a similar system for the standard pattern rebreather you see with my posts. The difference is that I use a Dry Suit inflator for the manual O2 add pulling out the adaptor and toggle valve...replacing it with an oxygen cleaned BC inflater hose. The orifice outlet goes directly into exhale part of the loop....sometimes through the CO2 monitor as I have explained earlier.

So simple, it is almost obscene...but it works like a charm.
I also carry a precision valve I can put in the system...why...cause I got it.

Tom Rose

**Dave Sutton** · 22nd February 2007, 20:23

Hey Tom, only a friend would mention it, but you seem to have a boat growing out of your head in the photo....

The orifice seems to work well, so that's good. Time to hold our "cheapest rebreather that you would dive to 100 feet for 30 minutes" contest. Or how about "Cheapest rebreather usable to 100 feet for 30 minutes with all parts except the 02 sensor(s) ordered from McMaster-Carr" contest....

Dave

Tom Rose · 22nd February 2007, 21:01

Quote: (Originally Posted by Dave Sutton)

Hey Tom, only a friend would mention it, but you seem to have a boat growing out of your head in the photo....

The orifice seems to work well, so that's good. Time to hold our "cheapest rebreather that you would dive to 100 feet for 30 minutes" contest. Or how about "Cheapest rebreather usable to 100 feet for 30 minutes with all parts except the 02 sensor(s) ordered from McMaster-Carr" contest....

Dave

Good eye Dave, that boat is about 45 feet above me. In photo class I was cautioned not to have trees grow out of the subjects head but they did not say anything about boats.

As for the contest....afraid that my time is slightly consumed by work and CO2 monitors....Later this year I would be ready to take the gauntlet on cheap rebreathers from McMaster Carr, Target, Wallgreens, Walmart, Kmart, Lowes, Monster Makers, and Home Depot.

**Dave Sutton** · 22nd February 2007, 21:47

Quote: (Originally Posted by Tom Rose)

Good eye Dave, that boat is about 45 feet above me. In photo class I was cautioned not to have trees grow out of the subjects head but they did not say anything about boats.
.

Photo should be captioned: "Diving Santa Claus is nabbed by underwater cops for erratic diving. Photo shows Mr. Claus being given a sobriety test. He blew a 1.2 (PP02)...."

Dave

denzel · 22nd February 2007, 21:58

WoW!

Finally a real home build, where most parts including but not limited to DSV are home made, and not sourced! (

)

Congratulations on a great looking unit, happy tinkering and many safe hours.

Have some green!

Denz.

koputai · 23rd February 2007, 00:57

Great news that the McMaster Carr set up works ok. I used to buy stuff from them, but now they sell to US addresses only. Anyone thinking of becoming a McMaster-Carr reseller for us non-US folk?

Cheers,
Jason.

Tom Rose · 23rd February 2007, 01:48

Quote: (Originally Posted by koputai)

Great news that the McMaster Carr set up works ok.

One caution here. I purchased 3 of the orifices from McMaster Carr. I tested them on a bubblemeter (a positive displacement device). I tried several filters. With the filter I finally used the highest flow rate was about .6 liters per minute at the surface. I thought that was just fine and have enjoyed diving it since.

The flow rate through those orifices varied about 10%. Not enough to worry me.

You need to verify the flow.....

ACCURATE FLOWMETER

or you can use the water displacement trick with a liter bottle.

No matter what, you cannot rely on the purchased size of the orifice...

Quote:

I used to buy stuff from them, but now they sell to US addresses only. Anyone thinking of becoming a McMaster-Carr reseller for us non-US folk?

Thats a shame....we get delivery over night from them at my office. If I call by 6 PM.
Tom Rose

Genesis · 23rd February 2007, 02:57

Those fittings look like John Guest tubing or some generic clone of it. Now THAT's a cute idea. They're used for commercial water tubing quite frequently (I have some around the house here) and they're rated to 250psi - that's not a bad idea at all! Inexpensive, seals tighter the higher the pressure, yet can be easily separated if you need to without tools.

marekm · 23rd February 2007, 03:55

Quote: (Originally Posted by Genesis)

Those fittings look like John Guest tubing or some generic clone of it. Now THAT's a cute idea. They're used for commercial water tubing quite frequently (I have some around the house here) and they're rated to 250psi - that's not a bad idea at all! Inexpensive, seals tighter the higher the pressure, yet can be easily separated if you need to without tools.

Hi Genesis,

That was perceptive of you to notice the type of fittings I'm using and the follow on consequences of having o-ring sealed fittings that can be dissassembled without tools. To be exact the fittings are carbon reinforced polypropylene Glasson brand agricultural water irrigation fittings, available from most hardware or plumbing supplies for a reasonable price. The internal diameter of the fittings is 25mm (not great, but its a start). If I could, I'd build the entire rebreather out of carbon reinforced polypropylene as its an non-offgasing, chemically inert, heat weldable, durable and robust material that can be injection moulded for mass production. But unfortunately I don't see an injection moulded rebreather coming out of China for $500 any time soon

Genesis · 23rd February 2007, 04:05

Yep.....

I've got the John Guest fittings on the water line for my espresso machine in the kitchen

Easy to take apart if you need to for some reason, totally leak-proof and easy to work with.

Easily available around here; our Home Depot stores carry them.

Its an interesting solution for gas tubing..... one I hadn't considered, but might have to - it not only works well and is totally inert but is also non-corrosive, trivial to fix if necessary (you can cut the tubing with a razor blade) yet its tough as nails and is rated for 250psi......

22nd February 2007, 20:23	#12 (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 Hey Tom, only a friend would mention it, but you seem to have a boat growing out of your head in the photo.... The orifice seems to work well, so that's good. Time to hold our "cheapest rebreather that you would dive to 100 feet for 30 minutes" contest. Or how about "Cheapest rebreather usable to 100 feet for 30 minutes with all parts except the 02 sensor(s) ordered from McMaster-Carr" contest.... Dave __________________ "Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com
(Offline)

22nd February 2007, 21:01	#13 (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: First pool dive on homebuilt rebreather Quote: (Originally Posted by Dave Sutton) Hey Tom, only a friend would mention it, but you seem to have a boat growing out of your head in the photo.... The orifice seems to work well, so that's good. Time to hold our "cheapest rebreather that you would dive to 100 feet for 30 minutes" contest. Or how about "Cheapest rebreather usable to 100 feet for 30 minutes with all parts except the 02 sensor(s) ordered from McMaster-Carr" contest.... Dave Good eye Dave, that boat is about 45 feet above me. In photo class I was cautioned not to have trees grow out of the subjects head but they did not say anything about boats. As for the contest....afraid that my time is slightly consumed by work and CO2 monitors....Later this year I would be ready to take the gauntlet on cheap rebreathers from McMaster Carr, Target, Wallgreens, Walmart, Kmart, Lowes, Monster Makers, and Home Depot. __________________ 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
(Offline)

22nd February 2007, 21:47	#14 (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 Tom Rose) Good eye Dave, that boat is about 45 feet above me. In photo class I was cautioned not to have trees grow out of the subjects head but they did not say anything about boats. . Photo should be captioned: "Diving Santa Claus is nabbed by underwater cops for erratic diving. Photo shows Mr. Claus being given a sobriety test. He blew a 1.2 (PP02)...." Dave __________________ "Silent Diving with No Bubbles and No Politics".... www.nobubblediving.com
(Offline)

22nd February 2007, 21:58	#15 (permalink)
denzel Holiday diver Current Rebreather/s: Inspiration Classic Other Rebreather/s: Not Bought Yet Join Date: Aug 2005 Location: Perth! Posts: 358	Re: First pool dive on homebuilt rebreather WoW! Finally a real home build, where most parts including but not limited to DSV are home made, and not sourced! ( ) Congratulations on a great looking unit, happy tinkering and many safe hours. Have some green! Denz. __________________ My deepest so far, 558.50 mtr, my rig a LF90D...
(Offline)

23rd February 2007, 00:57	#16 (permalink)
koputai Subsea Systems Current Rebreather/s: MK 15.X Other CCR Other SCR Other Rebreather/s: Not Bought Yet Other CCR Other SCR Join Date: Jul 2005 Location: Sydney, Australia Posts: 350	Re: First pool dive on homebuilt rebreather Great news that the McMaster Carr set up works ok. I used to buy stuff from them, but now they sell to US addresses only. Anyone thinking of becoming a McMaster-Carr reseller for us non-US folk? Cheers, Jason.
(Offline)

23rd February 2007, 01:48	#17 (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: First pool dive on homebuilt rebreather Quote: (Originally Posted by koputai) Great news that the McMaster Carr set up works ok. One caution here. I purchased 3 of the orifices from McMaster Carr. I tested them on a bubblemeter (a positive displacement device). I tried several filters. With the filter I finally used the highest flow rate was about .6 liters per minute at the surface. I thought that was just fine and have enjoyed diving it since. The flow rate through those orifices varied about 10%. Not enough to worry me. You need to verify the flow..... ACCURATE FLOWMETER or you can use the water displacement trick with a liter bottle. No matter what, you cannot rely on the purchased size of the orifice... Quote: I used to buy stuff from them, but now they sell to US addresses only. Anyone thinking of becoming a McMaster-Carr reseller for us non-US folk? Thats a shame....we get delivery over night from them at my office. If I call by 6 PM. 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
(Offline)

23rd February 2007, 02:57	#18 (permalink)
Genesis Bubbless Box of Death Current Rebreather/s: Home Build Other Rebreather/s: Home Build Join Date: Oct 2005 Location: Sunny Florida Posts: 1,453	Re: First pool dive on homebuilt rebreather Those fittings look like John Guest tubing or some generic clone of it. Now THAT's a cute idea. They're used for commercial water tubing quite frequently (I have some around the house here) and they're rated to 250psi - that's not a bad idea at all! Inexpensive, seals tighter the higher the pressure, yet can be easily separated if you need to without tools. __________________ "A venturesome minority will always be eager to get off on their own, and no obstacles should be placed in their path; let them take risks for Godsake, let them get lost, sunburnt, stranded, drowned, eaten by bears, buried alive under avalanches - that is the right and privilege of any free American." http://www.denninger.net http://www.diversunion.org/liability.htm - Fix the Diving Cert racket
(Offline)

23rd February 2007, 03:55	#19 (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 Genesis) Those fittings look like John Guest tubing or some generic clone of it. Now THAT's a cute idea. They're used for commercial water tubing quite frequently (I have some around the house here) and they're rated to 250psi - that's not a bad idea at all! Inexpensive, seals tighter the higher the pressure, yet can be easily separated if you need to without tools. Hi Genesis, That was perceptive of you to notice the type of fittings I'm using and the follow on consequences of having o-ring sealed fittings that can be dissassembled without tools. To be exact the fittings are carbon reinforced polypropylene Glasson brand agricultural water irrigation fittings, available from most hardware or plumbing supplies for a reasonable price. The internal diameter of the fittings is 25mm (not great, but its a start). If I could, I'd build the entire rebreather out of carbon reinforced polypropylene as its an non-offgasing, chemically inert, heat weldable, durable and robust material that can be injection moulded for mass production. But unfortunately I don't see an injection moulded rebreather coming out of China for $500 any time soon
(Offline)

23rd February 2007, 04:05	#20 (permalink)
Genesis Bubbless Box of Death Current Rebreather/s: Home Build Other Rebreather/s: Home Build Join Date: Oct 2005 Location: Sunny Florida Posts: 1,453	Re: First pool dive on homebuilt rebreather Yep..... I've got the John Guest fittings on the water line for my espresso machine in the kitchen Easy to take apart if you need to for some reason, totally leak-proof and easy to work with. Easily available around here; our Home Depot stores carry them. Its an interesting solution for gas tubing..... one I hadn't considered, but might have to - it not only works well and is totally inert but is also non-corrosive, trivial to fix if necessary (you can cut the tubing with a razor blade) yet its tough as nails and is rated for 250psi...... __________________ "A venturesome minority will always be eager to get off on their own, and no obstacles should be placed in their path; let them take risks for Godsake, let them get lost, sunburnt, stranded, drowned, eaten by bears, buried alive under avalanches - that is the right and privilege of any free American." http://www.denninger.net http://www.diversunion.org/liability.htm - Fix the Diving Cert racket
(Offline)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode