In a message dated 11/2/2009 6:55:19 A.M. Pacific Standard Time,
jonw@psubs.org writes:
Assuming the 12 and 20 inch descriptions provided by Frank are OD, then Hi Jon/all.
Sorry for the late reply but I was out of town for a while.
On my windows.......
The main window is 24 inch ID with a 2 inch wide X 1 inch thick base,
welded inside a 6 inch long sleeve of 3/8 inch steel and set so the 3 inch plexi
disk is flush with the outside of the sleeve.
The two smaller windows are 16 inch ID with the same base ring ( 2" X 1 " )
set to accept 2 inch thick disks.
This gives inside viewable diameters of 20 and 12 inches.
I've been talking to Hugh in New Zealand and I may have
to cut out the window sleeves and replace them with much thicker sleeves. This
of course will mean new base rings and a smaller window as I can't change the
ballast tanks and FRP fairings so the OD of the sleeve will need to stay the
same.
Still thinking on what the best solution is, but I will probably continue
with what's there for now and expect a much reduced dive depth.
The window assemblies can be removed next winter so I can still make the
convention with a working sub, although with a shallower depth rating.
Hugh mentioned a sleeve thickness of 1.25 inches for the large window and
.75 inches for the smaller windows. This will require some redesign of
weight balance as well, and who knows what else it changes.
It seems like the most straight forward fix at this point. Thanks for all
your input and I'll keep working on the front and rear bolt-on sections for now
as I study different solutions.
Frank D.
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