Do it your self Rebreathers???

[Duncan Price]

Iguana Don once bubbled...
You are playing with your life for a few bucks. There have been several deaths attributed to do-it-yourself rebreathers.

Can you cite examples? Given the preceeding estimate of number of units than we might be able to work out if they are safer than commercial units or not. I don't intend to start off Rebreather X is safer than Rebreather Y debate, I would like to examine whether homebuilts (as a "class") are safer or more dangerous than commercially manufactured units.

To avoid too detailed analysis - lets include all fatalities never mind if the rebreather was to blame (i.e. assume that you are just as likely to be attacked by a shark/have a heart attack on any unit).

I'm beginning to believe that if I had used the time I've spent making my own CCR working in a second job then I would have earned enough money (along with the cash outlay on my own unit) to have bought a commercial CCR and done a training course on it. The safety issue is a pertinent adjunct to this premise.

Duncan

 

[madmole]

To the best of my knowlegde there has yet to be a fatality in a home build

People going that route tend to be very conservative in their diving and give up and buy a proper unit

 

[Amphibious]

I'm just finnishing a pendulum O2 rebreather. we're out there....

20ft limit and 60mins for about $150. but warm and quiet and SOOO much fun to design and build!

I'll post picts after it's finnished.

Willer

 

[GrantInOz]

Amphibious once bubbled...
I'm just finnishing a pendulum O2 rebreather. we're out there....

20ft limit and 60mins for about $150. but warm and quiet and SOOO much fun to design and build!

I'll post picts after it's finnished.

Willer

When doing deco on pure 02, we tend to do back-gas breaks every 15 minutes.

How does this effect the use of a pure O2 rebreather?

Any thoughts?


Grant

 

[-BlueHole-]

Mr.Bubbles once bubbled...
I just came across this page. http://insel.heim.at/malediven/350052/reb_e.htm
What you think?

Mr. Kopka links, has also nice others do it yourself projects, like cannister lights and so on

 

[Amphibious]

GrantinOz: not sure about "airbreaks" with the O2 unit. I would think that the limited depth and small CNS loading because of the 20ft limit, (high PO2, but limit pressure for saturation) it would not be a problem, the one I'm building is a spin-off of Tom Rose's "Swamp Fox", and I only intend 60min dives with no exertion.

The trick for me right now is deciding on the best place for my O2 injection: just below the mouthpeice, or in the center of the scrubber?

Willer

 

[kavka]

I'll go for the scrubber, to heat up gas and there's one hose less conected to the mouthpeice

 

[Duncan Price]

kavka once bubbled...
I'll go for the scrubber, to heat up gas and there's one hose less conected to the mouthpeice

Check out my pendulum rebreather which has the manual O2 add right up by the mouth - the reasons to this are:

1. Can use a standard inflator.
2. You know where it is.
3. Every time you add O2 (about once every 5 minutes) you can drive any CO2 in the deadspace between the mouthpiece and scrubber into the scrubber.
4. If the scrubber floods you can manually inject O2 into your mouth so I don't normally carry an open circuit O2 reg as well (I always have other gas to bail out onto)

Apart from the srubber (which was made out of bits of plastic tube) it was made from bits you probably have lying around. I use it a lot of decompression whilst cave diving and tie it off at 6 m. I've also used it for shallow cave dives including a 500 m penertration. The scrubber lasts 2 hours but I don't normally run it longer than 1 hour (most deco use is around the 30 minute mark so I'll use it for two dives).

Duncan

PS. I don't bother with airbreaks. When using it for deco I purge the loop every so often to sweep out N2.