----- Original Message -----
Sent: Tuesday, October 03, 2006 5:34
PM
Subject: [PSUBS-MAILIST] It floats
I did as someone suggested and built
a model on my days off. using the half pipe design and some galvanize fence
material I was able to build a scale model
of the correct proportions but a little over weight. all tanks full of water
and it sank like a rock. adding air using a fish tank air pump and tubing to
the trim tanks only and she surfaced very well. After more testing determined
that neutral buoyancy will be fairly easy
to obtain and the main tanks will have more than enough lift for the sub and
then some.
thank you Frank, this is the number I am going to need to go
further make some better figures as to capacity
for equip and overall weight. I figure I have about 6 more months of
work before I can start getting materials ready to build my press hull and
ballast tanks.
thanks guys,
Chad Beller
-----Original
Message-----
From: ShellyDalg@aol.com
To: personal_submersibles@psubs.org
Sent: Tue, 19 Sep 2006 9:33 PM
Subject: Re: [PSUBS-MAILIST] hydraulic efficiency
questions
Hello. I'm not sure if I understand the question, but a cubic foot of air
displaces a set amount of water, depending on how compressed the air is. In
other words, a cubic foot of water ( which doesn't really compress much )
weighs 62.4 pounds. As a starting point, calculate how much water your sub
displaces, weigh the sub with all its parts and occupants and " stuff "
( again, calculate this rather than building one and putting it on a scale )
and what's left over is the positive buoyancy.
There are conversion charts on the psub site with weights, measures, etc. Down load and print and it
will give you a rough idea of how big/heavy a thing is.
Frank D.