----- Original Message -----
Sent: Monday, May 31, 2010 4:19
AM
Subject: Re: [PSUBS-MAILIST] through
hull reinforcement
Hi Hugh,
The way they fabricate the spherical portion of
the Deep Worker hull seemed
a bit difficult & probably expensive for
me. I'm guessing a die is made of the
right profile & the segments are formed
from flat plate pressed in this die.
You guys possibly know how it was
done.
I originally went down the track of trying to
find a cylindrical metal dome in NZ
but didn't come up with anything suitable.
After reading all the negatives about
fiberglass what probably clinched it for me
was a link Jon posted on a fiberglass sub that operated to 600ft back in the
70s.
The smaller you go the more attractive
fiberglass is as an alternative to steel, as its
strength goes up in relationship to it's wall
thickness & the diameter of the cylinder.
Once I've finalized the design & have the
interior of the polystyrene model perfect
I intend to poke hundreds of 1/2" pins through
the walls of the sub & sand down the exterior
to this level then fiberglass over it.
(relatively easy)
The bottom line is that if the engineer talks
me out of fiberglass or it's prohibitively expensive
I'll have to re-think it all.
Regards Alan
----- Original Message -----
Sent: Monday, May 31, 2010 11:48
AM
Subject: RE: [PSUBS-MAILIST] through
hull reinforcement
Alan,
Glad
to hear all that. Shame you weren’t at last P-subs convention as you
would understand what was done in the DW 2000.
If
you have everything cylindrical etc as you say then why are you not able
to make it from metal. Nothing surely can be that complicated. Is it
a weight factor? It is just that fiberglass is not generally used
for subs.
Looking
forward to seeing a concept. Chs Hugh
I have motor
controllers, valves, O2 & CO2 monitors, O2 regulator, pressure gauge,
compass,
etc etc. What I
haven't sorted is the through hulls as I'm not certain of the hull
thickness yet.
The batteries
are going either internal in a tubular section out the back of the pod
or
external
depending on what the engineer thinks, as this transition may be difficult
in fiberglass.
I haven't
designed the scrubber yet. I want to have two small scrubbers for the
reason you point
out, that in a
small space the margins for error with the life support system are less.
They have a
designated
space under my seat.
I have
concentrated on buying all the componentry so I can sit in my model with
everything in it & know
for sure it's
going to fit & I'm comfortable enough. If not just dig out some more
polystyrene.
Also there is
nothing in my hull design that's not cylindrical, conical or
spherical.
Re the
flotation; I'll be using inflatable pontoon type ballasts wich will enable
bigger ballasts without the
drag under
water. Additionally I'm looking at an acrylic sail like Emile has
that can pivot back through
180 degrees
& sit behind the pod while submerged.
Lots of work
but I'm further on than I was 2 years ago.
-----
Original Message -----
Sent: Monday, May
31, 2010 9:27 AM
Subject: RE:
[PSUBS-MAILIST] through hull reinforcement
Alan,
I
am not wanting to dampen your enthusiasm but I think you need to design
the scrubber, battery switches, VBT internal spare battery, Coms,
valves, motor controllers, etc and allow for your 72 hours safety
time and make mockups of those to put into your foam model. Cliff
Redus and Nuytco designs are as small as you can get them. Even
with fiberglass if you cant make them out of steel /alumiinium then the
design will have to be many times thicker. i.e. cylindrical /
conical / spherical designs are also going to be best for fiberglass as
well. Too small a personal space makes air control too
sensitive. Have you considered all this? Deepworker is about as
space conscious as you can get. Try and talk to Cliff. If
the space is too small then you will end up having to add a lot of
floatation. Just my penny’s worth. Hugh
Brian, the
hull is similar to Graham Hawkes "Aviator" wich was made out of cast
aluminum.
I'm trying to
make this as small as possible so that I have the convenience of
launching it off
the beach
etc. The shape is too complex for me to make out of
steel.
I'm designing
this using a simple pressure program & a large block of polystyrene
that I've carved out
to fit me
& the subs internal componentry. once finalized I can contour the
polystyrene exterior to within
.5" of the
interior & just fiberglass over the
outside.
The small
dimentions make it more suitable for using fiberglass. Mostly I'll be
about .5" thick (apart from reinforcements)
& this
will give me a 1000 ft crush depth for an operating depth of about
250ft. However this will be confirmed
once my final
design is analyzed. The composite engineering program will also come up
with a laminate lay up plan.
-----
Original Message -----
Sent: Monday,
May 31, 2010 1:07 AM
Subject: RE:
[PSUBS-MAILIST] through hull reinforcement
Why
are you making it out of fiberglass?
I need to
design the reinforcement of the area around my hatch
seat.
I've read
that with through hulls a general rule is you replace as much
material as has been removed
My sub is
small & is being made of fiberglass. At this stage I'm just
trying to get in the ballpark with
my design
calculations, as I intend to take take my drawings to a composite
engineer & get them
analysed
& corrected where necessary.
Would the
reinforcement be better on the inside of the hull, the outside, or
divided evenly on both sides.???
P.S. To
European & South African psubbers. NewZealand hot favourites for
the world cup.
__________ Information from ESET NOD32
Antivirus, version of virus signature database 5156 (20100530)
__________
The message was checked by ESET NOD32
Antivirus.
http://www.eset.com
__________ Information from ESET NOD32
Antivirus, version of virus signature database 5156 (20100530)
__________
The message was checked by ESET NOD32
Antivirus.
http://www.eset.com
__________ Information from ESET NOD32
Antivirus, version of virus signature database 5156 (20100530)
__________
The message was checked by ESET NOD32
Antivirus.
http://www.eset.com
__________
Information from ESET NOD32 Antivirus, version of virus signature database
5156 (20100530) __________
The message was checked by ESET NOD32
Antivirus.
http://www.eset.com