Solid 4 hour dive in cave on the BP60 today. did not have any CO2 issues, which makes me happy. I adjusted the O2 feed from 0.6 to 0.8 LPM which turns out is much closer to the right number for me. I did not have to manually add any O2 or diluent throughout the entire dive. One thing I did notice that was annoying: I develop a significant amount of lung phlegm at the exhaust side of the BOV. It does not travel further into the loop by itself, so after about 80 minutes it is sort of like exhaling into a shallow bit of water. The remedy seems to be go to an OC reg and hold the BOV over my head and shake the water down into the diapharagm area by jiggling the outlet hose. This seems to work for about an hour or so each time. Exhaling into the phlegm is not really a problem, just sort of annoying, and loud, compared to everything else. And some stats- 8.6CF of oxygen used through the orifice and then upped for 100% deco. 11CF diluent used, loop only, suit and wing are off bailout gas.
Ok, dave here are some photos-
Here are the banjo fittings that replace the original fittings. I got an original idea from someone on this board, but theirs were not easy to remove- mine have a fixed outer housing to which the pipe is soldered, and the inner bolt rotates for easy removal. (This is also how I test my O2 flow- the aft fitting comes out and screws into my flow meter.
This is the diapharagm retainer. It replaces the huge plastic case, as I wanted this rig as small as possible. It also adds some weight, being stainless steel. The rig can be removed in the water and pushed in front of me (you have to be open circuit, the BOV doesn't rotate) and with the two stainless brackets it is neutral in the water with the counterlung half full.
This is the O2 and DIL addition block. I dont like how the Kiss addition block flops around on its six foot cords, so mine is short and sits just below the right shoulder d-ring. So far, I have not had to use it at all during the dive, and I am debating the use of the diluent side at all- but perhaps I will find a reason to use it some day. Design note- the two sides are easy to confuse as the buttons are the same shape- it would be very easy to hit the wrong button. Fortunately, hitting either button will increase the O2, so it doesnt really matter. I dont train to decrease o2 by manual add- I exhale through the mask- the machine fixes itself with diluent addition. (I do plan to make the O2 button a different shape though.
Here is the whole rig ready to mount over my sidemount rig and go in the water.
Here is the magic- Notice that all of the plumbing is soft tubing- 250psi max with legris fittings. This stuff absolutely rocks. You just cant accidentally dislodge a fitting- I've tried, and they dont leak. I suppose they might eventually, but then I just swap out any of the fittings- 5 second job. Same with tubing. The orifices are so cheap they come in packs of 10- same with the filters. If they screw up (only did it once, before I added filters) I just swap the whole assembly. I can get back with the name of the orifice- I dont have the box with me.
