Re: [PSUBS-MAILIST] shapeable incompressable filler..any ideas?

[CARRO@wans.net]

I am concerned about corrosion occurring between your 
structure and filler material.  Small voids under 
pressure are going to fill with water and not drain 
out well.  Further, I'm not sure why you want to fill 
these voids, as they would weigh nothing out of the 
water and be filled with neutral buoyancy in 
compressible water when in use.  If you need extra 
flotation why not make a few ridged air canisters?  
Please excuse me if I haven't grasped the situation 
correctly.
--- Original Message ---
From: Erik Michael Muller <emm03@uow.edu.au>
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] shapeable incompressable 
filler..any =?us-ascii?q?ideas=3F?=

>Hello Marcus, and everyone.
>Thanks for your ideas..once again, the combined brain 
power of this
>mailing list has awe-inspired me!
>It is interesting, Marcus, I had a major revelation 
last night duing a
>bout of insomnia, and it occured to me that 
superballs were not very
>compressable (high resitituion too).  
>
>My brain rambled on and  I thought it might be 
possible to either use
>a big slab of neoprene rubber (not the foamy 
compressable wetsuit
>kind, but the solid rubber variety). although I think 
this might be
>expensive, so I thought I might be able to mix up a 
plaster+granulated
>neoprene conglomerate.  Some serious work would have 
to go into
>checking exactly what ratio would be the most 
durable, though even an
>integrity (sp) failure here wouldnt matter (i.e. it 
has no airspaces
>and cant crush, even if it cracks I wouldnt like it 
too, just because
>it looks messy), since the only function of the stuff 
is to fill
>volume. 
>
>The reason a conglomerate might be more useful is 
that rubber is less
>dense than water, whereas plaster (which IS 
waterproof) is more dense.
> The combined mix (depending on the ratio) might be 
at a similar
>density to water.
>Although the durability is not a safety concern, I 
would still like to
>vary the rubber/plaster ratio and test it out (since 
I suspect that
>plaster IS slightly porus!)..anyone with a boat who 
wants to sink a
>few test bricks of this stuff to a few atms?
>
>
>-------------------
>> Hello Everyone,
>> 
>> I was reading the machinery's handbook back at work 
and i found out
>that 
>> rubber,
>> although very elastic, isn't at all that 
compressable.  Could Erik
>use lots 
>> of rubber band
>> in this purpose, maybe bonded as needed to keep it 
in shape?  Any 1$
>store 
>> could
>> provide lots of them.
>> 
>> just a thought,
>> Marcus
>> 
>> 
>> ----------
>>                         ALLEN'S AXIOM
>>                 When all else fails, read the 
directions.
>>