Cressi Sub Titanium ellipse 1st & 2nd Stage

Any users of this regulator out there with any opinions as to this bit
of kit? Thinking of buying the Alaska version soon.....


--
WebbCMH
------------------------------------------------------------------------
WebbCMH's Profile: http://forums.deeperblue.net/member....fo&userid=4344
View this thread: http://forums.deeperblue.net/showthr...threadid=57908

In article <WebbCMH.1j08zm@forums.deeperblue.net>, WebbCMH
<WebbCMH.1j08zm@forums.deeperblue.net> wrote:

€ Any users of this regulator out there with any opinions as to this bit
€ of kit? Thinking of buying the Alaska version soon.....

No first hand experience, but in general the word "titanium" is a
manufacturer's code word for "let's rip off the clueless upper end of
the market with a hi-tech material they don't need, which won't give
any increase in performance, which could catch fire if used in high O2
environments, but that we can use to justify charging 3x what we would
for a brass regulator."

I don't think that has to do with titanium as much as it has to do with a
hydrocarbon introduced into a high o2 rich environment that ended up in
instantaneous combustion.

Pure oxygen does burn pretty damn hot.



"Alan Street" <agstreet@nonono_san.rr.com> wrote in message
news:170120051726411924%agstreet@nonono_san.rr.com ...
> In article <WebbCMH.1j0zdm@forums.deeperblue.net>, WebbCMH
> <WebbCMH.1j0zdm@forums.deeperblue.net> wrote:
>
> ? I know where your coming from Alan - but it is the lightness of the
> ? thing that appeals to me in as much as it will increase the confort
> ? level of my gums on long dives - I'm intending to buy it on a trip to
> ? the US in May where I can get it for $269 saving me some £77.00 on the
> ? same item here in the UK.
> ?
> ? I have titanium exhausts on my sports bike which are much lighter than
> ? the original one's and disapate the heat much much quicker than steel.
> ? I never heard of titanium catching fire in a high 02 environment - is
> ? this an urban myth or is there some creedance to the statement.
>
> La Jolla Shores, June 2000.
>
> Do a google search on "John Cain"

In article <nj5Hd.213729$Np3.8979272@ursa-nb00s0.nbnet.nb.ca>,
Acropolis <forsale@NOCRAPeasybikers.com> wrote:

€ I don't think that has to do with titanium as much as it has to do with a
€ hydrocarbon introduced into a high o2 rich environment that ended up in
€ instantaneous combustion.
€

You didn't read the thread, or do any research into the incident. This
fire was pretty much conclusively determined to be have been caused by
using a titanium regulator with 80% O2. Had is just been residual
hydrocarbon there woudln't have been enough fuel to sustain the fire
long enough to do the damage done in this event.

€ Pure oxygen does burn pretty damn hot.


Pure oxygen doesn't burn at all.


€
€
€
€ "Alan Street" <agstreet@nonono_san.rr.com> wrote in message
€ news:170120051726411924%agstreet@nonono_san.rr.com ...
€ > In article <WebbCMH.1j0zdm@forums.deeperblue.net>, WebbCMH
€ > <WebbCMH.1j0zdm@forums.deeperblue.net> wrote:
€ >
€ > ? I know where your coming from Alan - but it is the lightness of the
€ > ? thing that appeals to me in as much as it will increase the confort
€ > ? level of my gums on long dives - I'm intending to buy it on a trip to
€ > ? the US in May where I can get it for $269 saving me some £77.00 on the
€ > ? same item here in the UK.
€ > ?
€ > ? I have titanium exhausts on my sports bike which are much lighter than
€ > ? the original one's and disapate the heat much much quicker than steel.
€ > ? I never heard of titanium catching fire in a high 02 environment - is
€ > ? this an urban myth or is there some creedance to the statement.
€ >
€ > La Jolla Shores, June 2000.
€ >
€ > Do a google search on "John Cain"
€
€

WebbCMH <WebbCMH.1j0zdm@forums.deeperblue.net> wrote:

> I know where your coming from Alan - but it is the lightness of the thing
> that appeals to me in as much as it will increase the confort level of my
> gums on long dives

The second stage could be OK with high O2 as the pressure is much lower,
but if you get an s600 it is only 160 grams. The real thing that makes a
difference is to get a mouth piece like the Jax.

My 2 main regs are a TX50 (263 grams) and an s600. And on dives ranging
up to 90 mins I feel no discomfort with either. However with only 20
mins on a deco reg using a normal mouthpiece I really notice the
difference.

The only real benefit of a Ti or Al first stage is for flying as they
are much lighter.

I would never use one on anything over 40% O2 and would be very gental
turning them on with anything other than air. Both Ti and Al burn very
well in high pressure, high O2.

> • I have titanium exhausts on my sports bike which are much lighter than
> • the original one's and disapate the heat much much quicker than steel. I
> • never heard of titanium catching fire in a high 02 environment - is this
> • an urban myth or is there some creedance to the statement.

Titanium is grouped with Magnesium Beryllium and Aluminium and when they
burn, temperatures from > 2.000 °C <-> 3.200 °C are reached.

http://www.basf.de/en/ueber/dienste/...id=V00-CaC-r6C
pqbsf*_k

> The Material Titanium and it?s reactivity to gases and liquids Titanium
> requires an oxidising atmosphere to maintain it?s corrosion resistancey.
> It immediately produces a passive layer which durably protects against
> further corrosion. However, under certain circumstances, such as oxidising
> agents like oxygen, titanium can spontaneously pyrophically react. The
> start of such a spontaneous reaction depends on the concentration of
> oxygen, pressure and temperature. For static circumstances an O2
> concentration of minimum 47 % vol. is stated to cause ignition. For
> dynamic circumstances a concentration of 35 % vol. is stated.

Also if there are fine particles the ignition point will be lower. These
can be caused by wear.

http://www.firerescue.alachua.fl.us/...formation.html

> Class D - Flammable metals:

> Flammable metals such as magnesium and titanium generally take a very hot
> heat source to ignite; however, once ignited are difficult to extinguish
> as the burning reaction produces sufficient oxygen to support combustion,
> even under water.

And now having just read my own research I would never use or permit any
student I was responsible for to use either an Al or Ti first stage with
anything other than air. And I would warn any one else I saw using one
if they were going to use it with nitrox.



-- >replace spamblock with my family name to e-mail me

So the verdict is that Titanium is OK for Air but there is not a lot
going for it when used with Nitrox.......

Thanks everyone for your input and as I intend to train with Nitrox
later this year I will have to rethink.

Apart from the already mentioned s600 any other suggestions for a
lightweight flying friendly 1st and 2nd stage outfit with some cold
water ability?


--
WebbCMH
------------------------------------------------------------------------
WebbCMH's Profile: http://forums.deeperblue.net/member....fo&userid=4344
View this thread: http://forums.deeperblue.net/showthr...threadid=57908

>Subject: Re: Cressi Sub Titanium ellipse 1st & 2nd Stage
>From: "Acropolis"

>Pure oxygen does burn pretty damn hot.

Oxygen doesn't burn at all.

Capt. Bill

> Apart from the already mentioned s600 any other suggestions for a
> lightweight flying friendly 1st and 2nd stage outfit with some cold
> water ability?

Apeks ATX100 or ATX200. Fits all the spec you need and is cold water rated
from the factory.

Also has benefits of good hose routing (angled 1st stage ports), breathes
excellently (if set up correctly, but that's the same for nearly all regs),
and is inexpensive to service (servicing available worldwide as Apeks is
part of the Aqualung/Spiro/Technisub/US Divers group of companies).