Re: [PSUBS-MAILIST] canopy/bubble forming

["Rick & Marcia" <empiricus@telus.net>]

That would be my assumption.  Despite the extra toughness, I believe one
downside is that it scratches easier than acrylic.

Rick


----- Original Message -----
From: "Sean T. Stevenson" <cast55@telus.net>
To: <personal_submersibles@psubs.org>
Sent: Thursday, October 22, 2009 7:57 AM
Subject: Re: [PSUBS-MAILIST] canopy/bubble forming


> This would explain why diving helmets use polycarbonate faceplates - in
> the absence of a pressure differential, the cold-flow characteristic of
> PC makes it safer in a working environment?
>
> -Sean
>
>
> Phil Nuytten wrote:
> > Rick: Note that the link was on the blowing of polycarbonates -
> > Might want to think about the 'cold-flow' characterisrics of PC - that
> > what allows it to 'absorb' incredible levels of point loading that
> > would shatter acrylics like plexi-G - the material attempts to flow
> > away from the impact and dissipates the energy in that fashion. This
> > same ability will cause it to creep easily and deform under a
> > continously applied load such as that induced by external pressure.
> > That's why you don't see Lexan view ports or domes used in a chambers
> > or vessels with significant pressure differentials.
> >
> >     ----- Original Message -----
> >     *From:* Rick & Marcia <mailto:empiricus@telus.net>
> >     *To:* personal_submersibles@psubs.org
> >     <mailto:personal_submersibles@psubs.org>
> >     *Sent:* Wednesday, October 21, 2009 10:58 AM
> >     *Subject:* Re: [PSUBS-MAILIST] canopy/bubble forming
> >
> >     This is an excellent link for anyone wanting to form their own
> >     canopies or bubbles:
> >
> >     http://www.eng-tips.com/viewthread.cfm?qid=213295&page=4
> >     <http://www.eng-tips.com/viewthread.cfm?qid=213295&page=4>
> >
>
>
>
>
> ************************************************************************
> ************************************************************************
> ************************************************************************
> 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
************************************************************************
************************************************************************
************************************************************************