On the subject of G250's free flowing, the fact is that when you have a 
high performance regulator with a potentially very high flow rate, the 
temp is going to drop to below freezing on the first stage very rapidly 
in the event of a free flow. If this is an issue then you need to de-tune 
the G250 via the venturi and flow adjustment, or have it detuned at the 
bench for safety reasons.

I personally like the G250 as sensitive as I can get it but I must 
remember to de-tune it before removing it from my mouth, or off it go's. 
Also if your G250 free flows you must immediately stick your thumb on the 
mouth piece orifice  and this will stop the the free flow with no 
problems assuming it is not caused by ice or debris. The venturi 
adjustment is particularly effective at reducing free flow on a unused 
reg, and I wish that scubapro would put a large lever on it like the 
Beuchat VX-10.
 
I have seen people with surface free flows on their G250 and rather than 
simply using their thumb, bang it on the tank for a while before shutting 
off the valve. By then half their gas is gone. Then they will mumble 
about "defective regulator". May I suggest a Sherwood brut for you folks?

I'm not an ice diver, but the Atlantic can get kind of cold around here...

   Jim

On 1/8/99 3:46 AM Adri KC Haine wrote:

>Gentlemen,
>
>Looks like this ice-diving thread is becoming a free-flowing thread ;-)
>Anyway, In my experience it is VITAL that any diver who proceeds on a dive 
>under the ice, knows how to react in the case of a freeflowing regulator, 
>and is either able to close this valve himself, and do so very quickly!, 
>or has a buddy who knows exactly what first stage you are breathing on, 
>and can close it for you.
>Needless to say, DIR divers are at an advantage here, because their 
>equipment is configured in exactly the same way, so no guessing which 
>first stage to close!
>These skills can be practised in the pool or in shallow diving conditions, 
>as Ingemar stated. Also breathing from a freeflowing reg is possible, but 
>should be a last resort since your bottle will empty itself rather 
>quickly, and remember, you are in an overhead environment! A good buddy is 
>in such a case invaluable!! 
>
>JSUW@AO*.co* has  got another good point: 
>"Under the right (wrong?) conditions ANY regulator will free flow.  It is
>important in colder air temperatures to avoid breathing off of the regulator
>out of the water, so that it doesn't ice up prior to the dive."
>It is very important that you don't breathe, or try out your inflator, or 
>drysuit inflator, out in the air. Only when you are immersed can you do 
>these tests. This is a habit most divers have to break, because most will 
>try out their regs and inflators BEFORE entering the water. Don't do this 
>when you go ice-diving, or do it in a heated environment (if you have the 
>luxury of a heated kitting up room) Otherwise the first crystals will be 
>formed before the dive. Why? Because when there is ice on the water, you 
>can bet that the air temperature is even colder than the waters temp. So 
>the risk of the forming of ice crystals even when little air is passing 
>through the first stage is higher in the air than in the water, even 
>directly under the ice. 
>It is also important that the RMV of the diver during the dive is kept as 
>low as possible. Thats why we don't take beginners or known hoovers on an 
>ice dive. We try to keep the exertion to a minimum and avoid places with 
>strong currents. Also, when inflating the (obligatory, although I've known 
>people who go icediving with a wet suit - they usually do only ONE 
>icedive, afterwards, they either quit or buy a drysuit ;-) ) drysuit or 
>BC, work in short bursts, and preferably not while breathing from the same 
>first stage.
>All little things that make a lot of difference under the ice.
>
>just my 2p
>
>
>rgrds
>
>Adri Haine
>
>
>On another topic: has anyone noticed to what lengths the Wak two team is 
>going in explaining their exaggerated bottom times (see the january 6 
>update). Now they say they dropped their mapper and were proceeding while 
>mapping manually. Why have a XXXXX$ mapper and then not use it? Well, just 
>a thought or two from an innocent bystander ;-)
>---
>"The fair breeze blew, the foam flew, the furrow followed free
>We were the first that ever burst into that silent sea"
>
>Samuel Taylor Coleridge
>
>
>
>__________________________________________________________________
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