Re: Information Wanted

[Rick Lucertini <empiricus@sprint.ca>]

Martin Sanderse wrote:        [snip]   Before hitting the water I'd have a
professional check the design for

> stress concentrations though.  We don't talk about that much.
>
> Another thing to talk about is cold low cycle weakness of certain
> steels.  I'm reading about that now.

Here's one for the group.  For those of you with the patience and
engineering/scientific curiousity, build your pressure hull to scale in a plexiglass
model.  Bathe the model in polarized light while in a homemade pressure chamber (with
a window).

When viewed through another piece of plastic, stress concentrations will be seen as
"folds" and lines appearing before your eyes.  As you release the pressure, the lines
disappear.  Repeated "dive" cycles will eventually show up as permanent damage to the
model.  Concentrate on hatch areas, thru-hulls, etc.
--
Rick Lucertini
empiricus@sprint.ca
(Vancouver, Canada)

"Most people die with their dreams still inside them."