Re: [PSUBS-MAILIST] New to the list and to Personal subs!

[Ray Keefer <Ray.Keefer@ebay.sun.com>]

Hi Pedro,

Welcome aboard.

> Subject: [PSUBS-MAILIST] New to the list and to Personal subs!
> Date: Fri, 24 Mar 00 09:31:02 -0000
> x-sender: pedro@mail.pangea.ca
> From: pedro bedard <pedro@pangea.ca>
> To: "Psubs" <personal_submersibles@psubs.org>
> Mime-Version: 1.0
> 
> Morning all!
> Let me introduce my self, my name is Pedro Bedard. I am new to this list. 
> What is not new is my fascination with small submarines. So here I am to 
> ask for advice.
> My plan at this point is to attempt to build a small, one man, 
> electrically powered sub.

Good so far.

> A propane tank being the body I have chosen for 
> it's cheapness, shape and strength. Have I chosen wrong?

Ooooh. You just asked one of the biggest debateable questions on PSUBS!
Many of us don't recommend propane tanks since:
1. You really don't know the metalergy. By the time you send out a sample
   to get tested you could of had a custom hull.
2. Fumes in a used tank could be explosive.
3. You have to pass all your ribs and bracing down the conning tower.
   In a custom hull you can bring materials in through an open end.
4. You don't know the stress, strain, or abuse that tank has been through.
5. Propane tanks were not design to keep external pressures out, just to keep
   internal pressures in.
   
Others say, hey, it's ok if:

1. You are very conservitive. In other words derate seriously. Like if you
   figure it's crush depth (hard to guess at one unless you know the
   metalurgy and tempering) then operate at 20% of that.
2. Use only new tanks.
3. You can use used tanks but derate even more and figure out how to remove
   the propane fumes BEFORE welding or torching!
4. You WANT to die. :)


> I will in all likely hood be bugging listmembers about advice on drives, 
> hatch construction, port construction, in short, everything!
> Pedro Bedard 

Ask away. Visit the archive also.

> Wierd Canadian Praire Subbuilder

You are in good company. We have serveral Canadians here. I'll pass on the
wierd bit since I think we all are a bit wierd. :)

Regards,
Ray