Well, what else can one do when boredom sets in.  Our approach to the problem was a bailout rebreather to extend dive time in cave diving.  Criteria was that;  it had to be simple;  it had to cost very little; and oh yeah, it was expected to keep us alive.


So the project started by a visit to our local rebreather supply house in the area;  Lowe's and Home Depot.  Then a visit to my shop for time on my antique lathe.  Thus far we have put 40 mins on the scrubber.  We should get at least an hour plus.  The unit is an SCR (Semi-closed rebreather) with a flow control valve.  The flow is set for the nitrox mix being dove. 

As always things needed "improvement".  We had to add an anti-collapse system and used a central tube though the counter lung.  The end of this tube was a good place to mount the single PO2 monitor.  The original position low on the unit let all the water settle on the sensor, not the best.  We found that if you lost the mouthpiece you could hold the unit vertical and blow out the water through the OPV mounted on the bottom and just continue on.


lathe.jpg (2617109 bytes)

Machining O-ring face assembly.jpg (2705738 bytes) Assembling the system
pendpcs.jpg (370656 bytes) All the components pendc.jpg (32279 bytes) 1st generation assembly. 
dpwhat.jpg (404338 bytes)

You want me to do what?

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Dennis trying it out

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Dennis still on it

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Dennis with the 2nd generation  (O2 sensor placement)