----- Original Message -----
Sent: Saturday, October 29, 2005 12:06
PM
Subject: Re: [PSUBS-MAILIST] Propane
tanks
Hi Myles.
I would definately consider one for an ambient,
but no way for a 1 atm. There was some discussion here a long time ago
about
how the tank's holding internal propane pressure
did not necessarily cross over to keeping pressure out the same way. I can't
recall
what was said though, but I remember it was
discussed. Some guys have built them (1 atm) and I have seen some for sale
made from propane
tanks. But I'd want a thicker hull for a 1 atm if
it was me. I wouldn't trust a propane tank hull, even with reinforcement
rings.
I mean, if you are going to build a 1 atm with
all the trouble it takes....you might as well
make it where it can go relatively deep and build it with a thick
pressure hull
and get down 600 feet or more. Most
of the good non picked over wrecks are deeper than scuba depths because
the divers have already picked most of them over.
Most wrecks (okay not all) at scuba depths have
already been found too and there isn't much to discover new unless you go
beyond scuba depths.
But for an ambient? Like I said I think it would
be great for that for all the reasons you listed. I think it would be very
durable for an ambient and if
you are still contemplating building an ambient,
that would be an inexpensive way to go.
Bill.
----- Original Message -----
Sent: Saturday, October 29, 2005 8:39
AM
Subject: Re: [PSUBS-MAILIST] Propane
tanks
Bill.
Yes, agreed. When I was
looking into the feasibility of a propane tank pressure hull, I was
certainly only thinking of a new one. There is no way in hell I would
put my torch to a used one. The reason I was considering one as a
possibility is because:
1) I'm not looking to go very
deep.
2) They are, by their very nature,
pressure vessels complete with hemi-spherical end caps.
3) Cost. Being mass produced, you
would expect them to be relatively cheaper than a scratch
build.
4) Availability.
5) Convenience of having a pressure hull
with end caps already.
Having said all that, if I'm taking the time to
cut, grind, and weld, I was just as soon scratch build a hull that is a
little more durable.
I don't know, it was something I was pondering
but I'm leaning towards a scratch build.
Myles.
----- Original Message -----
Sent: Saturday, October 29, 2005 2:29
AM
Subject: Re: [PSUBS-MAILIST] Propane
tanks
Hi Myles.
There have been some subs made from propane
tanks but most of the knowledgeable subbers shun them.
Because...
1. They can explode from residual propane
when you grind cut or torch them.
2. They are of an unknown metalic
strength.
3. They are usually too thin for deep
dives.
4. The interior of an empty one may be
corroded if the valve was left open and hence you have something useless
when you cut it open.
There are some other reasons I have heard of
too, but that's all that comes to mind right now.
If you do use a propane tank I have always
heard to make sure you buy a brand new one that is shipped to you without
any gas ever having
been put into it. Then it is safe to grind
cut or torch.
I wouldn't use one for a pressure hull
myself, but I think they might be good for an ambient.
Bill.
----- Original Message -----
Sent: Friday, October 28, 2005 8:20
PM
Subject: Re: [PSUBS-MAILIST] remove
me second kind request
Patrick,
Speaking of propane tanks for
pressure hulls, is there any merrit to that, convenience or expense
wise, or is a guy just as smart to scratch build the hull ?
Have you done any research on
the propane tank thing ?
Myles.