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 Eric Maiken asked:

>What do you think about the adjustable 2nd stage knobs 
>(ala scubapro dial-a-death or the different exo design) as a 
>way to start/stop/slow a 2nd stage freeze-up?

I kind of like them.  If you adjust your second stage right to the edge of
freeflow (as you can easily do with any of the dial-a-breaths) you run the
risk of even the smallest bit of ice starting your reg down that road.  But on
the other hand you can use the system to increase spring tension to help keep
the reg from going off.  Once a freeflow starts I've never been able to stop
it using the dial-a-breath adjustment *except* on the Sherwood Maximus where
you can actually shut the air off at the second stage.  This is one of the
great things about this reg.  That and the fact it has the least propensity to
have a problem in the first place! 

>Have you ever manifolded redundant open circuit rigs(with say a ball valve 
>switch and/or double-end-shut-off quick disconnects) to the ffm as found on 
>bail-out rigs for surface supply?

Humm.  Not sure what you mean.  The EXO has an optional Manifold block so that
you can use the rig with an umbilical and have a bail-out bottle.  You could
use this manifold to provide two first stages to the EXO but that doesn't help
with a freeflow as this is due to the second stage (in the FFM).  You could
attach a second stage (octopus) to the manifold but you can do that right to
the first stage.  We normally use two completely independent regs.  The
primary would be connected to the FFM and the secondary would have a
conventional second stage.  You still end up having to ditch the FFM to use
your backup system.   PS: I don't normally use one of those neoprene polar
caps with a FFM.  They tend to make the FFM leak on my face.

>do you have an opinion on the over-pressure relief valves used on a 
>bail-out block (particularly regarding the lube/oring/entrapped 
>freshwater)? 

We use them on our bail-out regs for surface supplied diving.  If you go deep,
you need some way to relieve the pressure in the bailout whip on the way up. 
Normally you would not be breathing the pressure off on this hose.  You're
right, it is one more o-ring etc, but it beats having to rely on a procedure
of opening the emergency gas valve on your hat for ascents.

Cheers-  Rob

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