|
Make sure you use water as the pressure fluid... don't
presume that a scale model is going to react the same... extruded vs continuous
cast vs cell cast, age, previous chemical exposure, etc... soooo many
variables! Be berry careful about your assumptions... often it's what you
don't know or don't test that bites you in the end. What's the saying... a
little bit of knowledge is a dangerous thing. Tis so true.... there are so many
crackpot 'scientists' that are convinced of faulty conclusions based on small
bits of test data. Don't be deluded into thinking that just because one
quickly build scaled window design didn't break at some short pressure test
doesn't mean that it's going to be 'safe' for use.
Testing is essential, but make sure the design of your
tests covers all the bases.
I'm feeling old and conservative tonite... :)
Mark
----- Original Message -----
Sent: Wednesday, August 22, 2007 10:52
PM
Subject: RE: [PSUBS-MAILIST] Aqua Jet
Cutting Acrylic
Wil,
Interesting Idea you have. My friend Lou, that
manufactures stainless steel tanks, has a hydraulic pump that can go up to
1200 psi, which would be like 2694 fsw. We could build a special but small
stainless steel tank with a viewport in it and then fill it with hydraulic
fluid and test it to destruction, unless the viewport tested can with stand
more then 1200 psi. Of course we will need to take into account fatigue
cycles as well as different temperatures, as well as a few
other things. This type of set up can test different types of
polycarbonate viewports as well. I can take digital videos of each test and
share them with the group.
Regards,
Brent
Hartwig
> Date: Wed, 22 Aug 2007 14:08:15
-0700
> From: clientes@tolimared.com
> To:
personal_submersibles@psubs.org
> Subject: Re: [PSUBS-MAILIST] Aqua Jet
Cutting Acrylic
>
> May i suggest a practical approach on
this...
>
> The core of the problems seems to be that many of us
just want to use
> a simple acrylic disc piece that you can get in a
normal acrylic store
> - where they do decorative items more than
submarines - and use it as
> a viewport. The truth is when you get your
arcylic disk you do not
> know exactly what process it is trough or not
- it looks good - and
> you do not want to build a computerized heating
facility just to be in
> peace with the Professor or ABS you also do
not want to convert in
> acrylic scientific you just want to know what
is safe.
>
> The question that arises is : IF they did NOT
anything right in the
> factory - (which is a remote or not so remote
posibility) what is the
> depth i can do with this - and still be on
safe side. Is it fine to do
> half of stachiew and ABS and forget about
all those complicated
> proeedings? - or should it be 1/3 ?
>
> So i would suggest somebody who has a water yet and a hydraulic pump
> available cuts out a model series 1:2 from sheet material and tests
it
> to destruction in a simple mounting inside a hydraulics cylinder -
> with and without annealing...shrinking...
>
> And
hopefully publishes this - of course no guarantee - on this forum.
>
> What is of interest for us all is what is the DIFFERENCE - and a
> educated guess on that.
>
>
> Cheers Wil
>
(concretesubmarine.com)
>
>
>
>
>
>
Quoting irox <irox@ix.netcom.com>:
>
> >
> > [I
have to admit I'm a little shy about posting to this thread given
> >
some of the things people have said recently, but, here goes
anyway...]
> >
> > Other than Dr. Stachiw stating in his
book that all Acrylic viewports
> > require annealing, there are some
other things I would consider when
> > thinking about this
question.
> >
> > Cast Acrylic viewports require annealing.
I expect cast Acrylic to be
> > closer to 'prefect' than any form of
cut Acrylic, but it still requires
> > annealing.
>
>
> > Other than annealing, you are also required (by ABS[1]) to
preform
> > a shrink cycle. The equipment and effort required for the
shrink
> > cycle is pretty close to what you need for annealing, so
skipping
> > the annealing process wouldn't save much anyway.
>
>
> > Ian.
> >
> > [1] - Yes, yes, I know, psub
builders are not required to conform to
> > any ABS
standards...
> >
> > -----Original Message-----
>
>> From: Brent Hartwig <brenthartwig@hotmail.com>
> >>
Sent: Aug 22, 2007 10:49 AM
> >> To:
personal_submersibles@psubs.org
> >> Subject: [PSUBS-MAILIST] Aqua
Jet Cutting Acrylic
> >>
> >>
> >>
>
>> Hello Joe,
> >>
> >> I agree with your
approach. I was pursuing information to prove it
> >> or not, if
the information was to be had from the groups knowledge
> >>
base. I plan to anneal my aqua jet cut view ports, unless I get
>
>> good solid data otherwise. I was just interested in finding out if
> >> I had found a way to cut out one step out of the
process.Brent
> >>
> >> P.S. It looks like Frappr.com
is down for a bit.
> >>
> >>> From:
joeperkel@hotmail.com> To: personal_submersibles@psubs.org>
>
>>> Subject: RE: [PSUBS-MAILIST] Open Discussion's Allowed in PSUB's
> >>> Mailing List> Date: Wed, 22 Aug 2007 10:57:43
+0000> > Brent,> >
> >>> Something like the
acrylics issue, my approach is to consider all
> >>> ideas
> "suspect" until proven otherwise.> > If there is no
>
>>> reference to the "non-annealing" of water jet cut acrylics in
> a
> >>> highly specialized and expert Stachiw type
reference, then it is
> >>> best to > "assume" it to be a
required process based upon the
> >>> previously existing >
processes.> > Joe>
> >
> >
> >
>
>
> >
************************************************************************
>
>
************************************************************************
>
>
************************************************************************
>
> The personal submersibles mailing list complies with the US
Federal
> > CAN-SPAM Act of 2003. Your email address appears in our
database
> > because either you, or someone you know, requested you
receive messages
> > from our organization.
> >
> >
If you want to be removed from this mailing list simply click on the
>
> link below or send a blank email message to:
> >
removeme-personal_submersibles@psubs.org
> >
> > Removal of
your email address from this mailing list occurs by an
> > automated
process and should be complete within five minutes of
> > our server
receiving your request.
> >
> > PSUBS.ORG
> > PO
Box 53
> > Weare, NH 03281
> > 603-529-1100
> >
************************************************************************
>
>
************************************************************************
>
>
************************************************************************
>
>
> >
>
>
>
>
>
>
>
>
************************************************************************
>
************************************************************************
>
************************************************************************
>
The personal submersibles mailing list complies with the US Federal
>
CAN-SPAM Act of 2003. Your email address appears in our database
>
because either you, or someone you know, requested you receive
messages
> from our organization.
>
> If you want to be
removed from this mailing list simply click on the
> link below or send
a blank email message to:
>
removeme-personal_submersibles@psubs.org
>
> Removal of your
email address from this mailing list occurs by an
> automated process
and should be complete within five minutes of
> our server receiving
your request.
>
> PSUBS.ORG
> PO Box 53
> Weare, NH
03281
> 603-529-1100
>
************************************************************************
>
************************************************************************
>
************************************************************************
>
|