Re: Hatch Safety?

[protek@shreve.net]

Paul,
    I thought about all this long and hard.  I had the same fears of how do
"they" get the hatch open.  I designed a shaft and housing with o-ring
seals packed in grease.  The housing is welded into the hatch top and a
wheel is attached on both inside and outside.  This is much the same as you
see on the movies.  The only problem with mine is that the outside hatch
opens clockwise.  If the support crew knows this good.  If not, you had
better tell them.  I also have my viewports removable with allen wrenches.
I have a supply of allen wrenches.  If the hatch jammed I could be passed
air from outside.
    The explosive bolts may not be a good idea.  For one thing, if you used
them with an outside scuba diver around he would never hear again probably.
 I designed my hatch with a lip that is about 5/16 inch from the mounting
flange.  This allows a crow bar approach if need be.  My worst fear is for
the sub to on the bottom and to roll over into the mud or silt where I
could not open from inside.  In such a case a crow bar could be used.

GB


At 11:28 AM 2/26/99 -0600, you wrote:
>I have noticed that many PSUB designs latch the hatch :) from the inside
only.  They cannot be opened from the outside.  I assume that this poses a
safety risk to the operator, in case of emergency rescue.
>
>One, is there a reasonable PSUB way to latch the hatch such that it can be
opened from both sides?
>
>Two, sci fi movies and books often use "explosive bolts" to blow a hatch.
Are explosive bolts available to Joe Friendly Homebuilder?
>
>Three, does it really matter, since there will most likely not be a
successful emergency rescue?
>
>I would appreciate all comments, and I FULLY understand that my life is my
own responsibility, and that nobody else wants to assume any liability.
>
>Thanks,
>Paul Julius
>Crazy student psubber wannabe
>
>