Atomic B1, when installing 'christolube', how full should 1st-stage be?

scubafanatic · Oct 14, 2007

I've got an environmental kit on my B1 st-stage, with respect to the correct amount of christolube, how 'full' should the 1st-stage be, should the main spring chamber be 'stuffed' with christolube, to correctly transmit the ambient water pressure to the relevant components?

Thanks,

Karl

paulwlee · Oct 15, 2007

It should be completely full. Ideally, without any air pockets although that's probably not easy to achieve.
If the air pocket is too large there might be a possibility that the ambient chamber won't see the full ambient pressure. In a full chamber, lube is not compressible, so the water can exert pressure through the trim ring on the lube, and the chamber will see the ambient pressure. If there is an air pocket, air is compressible, so for the pressure to be the same, something(water) will have to move in through the holes. Unfortunately the trim ring hinders this, so the insides of the ambient chamber may end up being at a lower pressure than ambient. The symptom will be the regulator becoming very hard to breath at depth, and being normal at shallow depths. I believe this once happened to someone with an Atomic regulator.
But then I've only read one instance of this, so as long as it's full enough (meaning some lube oozes out the holes when it's first pressurized) it should be fine.

just-a-diver · Oct 15, 2007

1.5 oz. anymore is to much

DA Aquamaster · Oct 15, 2007

I can't address Atomic regs in particular, but they use the same basic system that Scubapro used in their SPEC system - back when the Atomic engineers worked for Scubapro. (In my opinion SP made a big mistake moving away from the SPEC system in their piston regulators and shoudl have updated it by switching to Christolube rather than switching to the TUS system in their piston regs.)

It's best to avoid any air pockets when packing the ambient chamber, in part becuse of the compressibility issue, but more importantly as it creates the potential for water to migrate into those voids oiver time creating the potential for ice crystals to form inside the ambient chamber in areas where they could still impede the movement of the piston, spring, etc.

Acheiving that is a bit of an art and requires some thought during the packing process. I normally would fill the lower area of the reg body as well as the spaces in the spring and then install the parts and work up from there with the goal of creating a situation where any remaining air was forced out the holes followed by a small amount of lubricant. Perfection is not acheivable but you can come close enough and perhaps more importantly ensure none of the voids are deep inside the reg and/or are in direct contact with any moving parts.

knotical · Oct 15, 2007

The packing tool shown here (the fourth tool down) helps.
Custom Peter Built Atomic Aquatics® Tools

scubafanatic · Oct 16, 2007

knotical:
The packing tool shown here (the fourth tool down) helps.
Custom Peter Built Atomic Aquatics® Tools

Thanks knotical, that's a pretty interesting link!

Karl

scubafanatic · Oct 16, 2007

DA Aquamaster:
I can't address Atomic regs in particular, but they use the same basic system that Scubapro used in their SPEC system - back when the Atomic engineers worked for Scubapro. (In my opinion SP made a big mistake moving away from the SPEC system in their piston regulators and shoudl have updated it by switching to Christolube rather than switching to the TUS system in their piston regs.)

It's best to avoid any air pockets when packing the ambient chamber, in part becuse of the compressibility issue, but more importantly as it creates the potential for water to migrate into those voids oiver time creating the potential for ice crystals to form inside the ambient chamber in areas where they could still impede the movement of the piston, spring, etc.

Acheiving that is a bit of an art and requires some thought during the packing process. I normally would fill the lower area of the reg body as well as the spaces in the spring and then install the parts and work up from there with the goal of creating a situation where any remaining air was forced out the holes followed by a small amount of lubricant. Perfection is not acheivable but you can come close enough and perhaps more importantly ensure none of the voids are deep inside the reg and/or are in direct contact with any moving parts.

Hi DA Aquamaster,
...I'm concerned about the 'compressibility' issue as well, since I've owned the reg I've had it serviced at 3 different Atomic dealers, and it's come back messed up from botched annuals from 2 of the 3 dealers...... came back with issues like 'creeping IP' , and IP set at 110-115 psi.
I've had it upgraded to the new B2 piston, and had shims installed to get the IP to about 135 psi, but the last 2 dive trips I took I put it back in the dive bag after one dive and went to a back-up reg, it just doesn't put out air as effortlessly as before servicing, even moderate effort made me feel as if I was about to overbreathe it !
...so, I'm thinking the next areas to review are the christolube 'levels' and readjust the sensitivity of the 2nd-stage.
Although I hate shipping regs out for service, I'm considering shipping it directly to Atomic for another service.

Karl

scubafanatic · Oct 16, 2007

paulwlee:
It should be completely full. Ideally, without any air pockets although that's probably not easy to achieve.
If the air pocket is too large there might be a possibility that the ambient chamber won't see the full ambient pressure. In a full chamber, lube is not compressible, so the water can exert pressure through the trim ring on the lube, and the chamber will see the ambient pressure. If there is an air pocket, air is compressible, so for the pressure to be the same, something(water) will have to move in through the holes. Unfortunately the trim ring hinders this, so the insides of the ambient chamber may end up being at a lower pressure than ambient. The symptom will be the regulator becoming very hard to breath at depth, and being normal at shallow depths. I believe this once happened to someone with an Atomic regulator.
But then I've only read one instance of this, so as long as it's full enough (meaning some lube oozes out the holes when it's first pressurized) it should be fine.

Thanks for the info, paulwlee.....your explanation makes sense and it may be why my B1 just doesn't perform as well as it used to, even though it was just serviced.....that shop gave it back to me with an IP of 110-115 psi, way below spec, and I had a second shop install 3 shims on the mainspring to get that back up to about 135 psi, but it's still not performing as it did before the annual...very frustrating!

Karl

superstar · Oct 16, 2007

Why do you need to pack the chamber with Christolube rather than Dow Corning 111 ???

paulwlee · Oct 18, 2007

superstar:
Why do you need to pack the chamber with Christolube rather than Dow Corning 111 ???

My understanding is that Christolube is a better lubricant, but more importantly Dow Corning 111 is not Nitrox compatible. I guess it would be OK if you only used air in your regulator, but then for the manufacturer it's a major liability headache when regulators start catching fire because they didn't idiot-proof the service procedures.

Atomic B1, when installing 'christolube', how full should 1st-stage be?

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