On Thu, 15 Oct 2009 11:13:21 -0400, Tom Francis - SWSports
wrote:

On Thu, 15 Oct 2009 10:07:34 -0500, Vic Smith
wrote:

On Thu, 15 Oct 2009 08:53:50 -0400, Tom Francis - SWSports
wrote:


I watched their attempt to use duct tape to patch a hole from under
water with some interest.
Half-assed worked.
A special adhesive formulation that sticks better - to put in the
emergency kit - would probably sell to boaters.

They went about it wrong - a patch isn't going to work.

Whipping up a ball and/or plug would have been perfect.

Just like their drill made perfectly round hole.
I suspect most holings in glass are jagged and take odd shapes.
And there's probably no time to whittle.
My 2 leading ideas for emergency patching holes in glass caused by
hitting debris, both applied from the outside by diving overboard,

2. A glue attached patch that could be unfolded and slapped over the
hole. Something like visqueen. Maybe with a backing that is pulled
off to activate/expose the glue. Couple feet square should do, but
could be various sizes.
Trouble is I haven't seen a suitable underwater glue.
Some talk about developing them by copying barnacle secretions, etc.,
but nothing I've seen on the market that is fast and sticky
underwater.
Seems the best thing might actually be a tube of roofing patch tar,
applying a wide bead with a caulk gun around the hole, then slapping
the sheet of visqueen on it. Just an idea, and I don't know if it
would work. But I'd love to try it if I lived by real water instead
of just rain. Damn it, I've seen about 2 hours of sun since I got
back from Florida a couple weeks ago.

So, number 1 choice is.......

1. A PFD-like bag, suitably sized, that can jammed in the hole, and
inflated by pulling a CO2 lanyard.
Pleating to accommodate hole jaggedness, flexibility/ toughness of
material, and inflation pressure are the main engineering issues.
Not exactly rocket science, but still....

These are quick and dirty measures to stop most inflow and give the
boater a chance to dewater by pumping/bailing, and make a more
permanent patch if possible.
Not as a replacement for normal damage control plugs, which are fine
for a broken thruhull for example.
Big ships carry timbers to shore a mattress against a hole in the hull
and all kinds of other crap.
Wouldn't be prudent to carry such on a 20' Carolina Skiff.
Now I have to go.
Time to study life rafts, and maybe a device/tool/kit to assist in
righting a capsized boat.
So many problems to solve, so little time.

--Vic