CCR Selection priorities

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Honestly, I'm waiting for the 'agency that shall not be named' to adopt that flex manifold and create an approved OC sidemount configuration. :-D
with or without a valve at the back of your neck? :p
 
except for the whole selective leaking of helium thing

I hate that. I keep my isolators closed while the rack is stored. Easy enough to manage if you follow the checklist and do a flow check, but closing them routinely still offends my traditional doubles sensibilities.
 
I hate that. I keep my isolators closed while the rack is stored. Easy enough to manage if you follow the checklist and do a flow check, but closing them routinely still offends my traditional doubles sensibilities.
I dont totally understand but why not use the RB80 style manifold? Does it not fit?
 
I am not 100% familiar with the set up, what selective leaking of helium?
The flexible hose between the lola valves (used in the GUE-JJ configuration) is porous to helium molecules and they will gradually leak out over time. The nylon seats in conventional valves are too, but the surface area of the hose is so much larger its actually relevant and your 15/55 becomes 15/50 over the course of a month or two if you leave the hose pressurized.
 
I hate that. I keep my isolators closed while the rack is stored. Easy enough to manage if you follow the checklist and do a flow check, but closing them routinely still offends my traditional doubles sensibilities.
Agreed. I was pre-warned about the leaking so I always keep the isolators closed but it really bothers me. It feels like I’m setting myself up to make a mistake. Though hopefully my caution of the manifold being closed will keep me attentive to it.

I am not 100% familiar with the set up, what selective leaking of helium?

There is an individual isolator on each valve. They tend to leak helium if ithey’re left open.
 
The flexible hose between the lola valves (used in the GUE-JJ configuration) is porous to helium molecules and they will gradually leak out over time. The nylon seats in conventional valves are too, but the surface area of the hose is so much larger its actually relevant and your 15/55 becomes 15/50 over the course of a month or two if you leave the hose pressurized.

I didn’t realize it came through the hose body. I assumed it was around Orings or the seats.
 
I didn’t realize it came through the hose body. I assumed it was around Orings or the seats.
Sadly it's the actual hose. All plastics have some porosity to helium, the hose just happens to be a very large surface area compared to something like a valve seat which is 2mm
 
I dont totally understand but why not use the RB80 style manifold? Does it not fit?
The old RB80 style manifold is a pain in the ass.

you’ve gotta cut and tap an isolator, thread in swagelok fittings, cut and bend stainless tubing, press on the fittings, angle everything just right, mess up the length and have to cut tubing again, go back to the pneumatics store and get more fittings cuz you buggered one up, assemble again, leak test, drain and reassemble because there’s a baby leak, assemble again, everything holds, whack the ceiling, bend the hose, looks like doodoo, start at the 1st line again and do it all over.

ok that was kind of therapeutic. Big sigh of relief.

lola manifold is way better even if I have to close and open the isolator.
 

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