The theory behind cardboard

[HUNTR2@aol.com]

In a message dated 7/4/99 6:43:07 AM Pacific Daylight Time, 
jawillia@eskimo.com writes:

<< 
 Gene,
 
 Your mention of the cardboard being stiff has it's merits.  I once saw a
 bridge made from the stuff that you could drive over.  It was a proof of
 concept but a pretty good one.  If one were to take the stuff and
 saturate it with epoxy (similar to the WEST system) and roll it on the
 inner hull, then finish it to just slide into the outter hull, wet both
 surfaces with epoxy and bingo.  Just a thought.
 
 Jim >>
Hi Jim,  
	... an interesting thought too.  You must be reading some of the 
archive to the psubs website.  I used that analogy for a honeycomb filled 
double hulled sub a while back.  The strenght and stability comes from the 
distance between the two hulls.  The greater the distance (provided the 
honeycomb is attached and strong) between the hulls the more resistence to 
bending or distortion.  How deep could you go with CONTINUOUS ring stiffeners?
	There was discussion different materials and how to inspect between 
the hulls, how to do hull penetrations, etc.  all which could have engineered 
answers.  For a one time builder there is lots of risk doing something new, 
and the archives are full of warnings about the need for qualified 
engineering and TESTS, TESTS, and cycling tests, but then again, if nobody 
brainstorms, there is no progress.  I'd love to design something like this 
and see just how far down I could sink it before the "thwump".   ahhh  it 
only takes $$$$$ and time...   The first step would be to get input from a 
qualified, experienced engineer which I'm not.  They could take some of the 
trial and error out of the process.

Gene Seus