Quote: (Originally Posted by GKAM)
Hi AD_ward9, I think our friend here is trying to build an O2 rig. ppO2 monitoring is not an issue I would guess. But you are right about channeling.
I was diving an O2 homebuilt some years back based on a bike inner tube and PVC pipe. To prevent channeling I improvised a system to keep the scrubber material tighly packed. Some pics are still up at
http://www.kamarinos.com/rebreather/DIY_CCR_EN.html
btw, inner tubes are extremely duarable and fairly inexpensive. You can easily build a couple of sets for next to nothing. However, you must first do several thorough washes with hot soapy watter to get rid of the rubbery taste and smell
Sorry, after starting I had an interruption for an hour, and when I got back forgot it is an O2 Rebreather. You are right of course.
Your unit looks very neat and tidy. The screw clamp you use to compress the lime is the thing to use, rather than the bayonet linked earlier in this thread.
Makes one think what is the minimum possible config. Probably a tube, clamped to an Extendair cartridge, the breathing hoses with their mushrooms, and an injector valve. It would be under $70 even if one bought everything. All the cost is the breathing tubes and mouthpiece.
I still don't like car inner tubes: black plastics are usually UV tolerant, but inner tubes are not: I use them for holding a holding net on the surface when spear fishing (using a snorkel) and have been through a few. This is in Scotland where the UV is pretty low. Put a cordroy sleeve over it and it would last much longer. Silicone is also more hygenic all around.
Cheers,
Alex