Slumping mirrors.

If you want a slumped mirror, you will have to mirror probably with silver
after the slumping is done.
The curved mirrors used for observing traffic (at alleys, etc.) are quite
weather resistant, so what do you need more.
If the glass has stainless steel in the middle, it won't slump. Aluminium
will melt and flow. Laminated glass has plastic in the middle which is
destroyed long before the glass slumps. Silver is always applied on one
side.

--
Mike Firth
Hot Glass Bits Furnace Working Website
http://users.ticnet.com/mikefirth/I-UPSUMM.HTM
shows recently changed files, click on link
"Ian Stirling" wrote in message
...
Is there commercially available glass with a mirrored layer in the middle?

I'm looking for a very weather resistant mirror, that can be slumped
into shape.
Stainless steel is of course an option, Aluminium will tend to tarnish
quite rapidly, and plastics are out due to lack of UV stability.

Thoughts?

--
http://inquisitor.i.am/ | | Ian
Stirling.
---------------------------+-------------------------+--------------------
------
"When I use a word," Humpty Dumpty said in a rather scornfull tone, "It
means
Just what I choose it to mean - neither more nor less." -- Lewis
Carrol

Mike Firth wrote:
If you want a slumped mirror, you will have to mirror probably with silver
after the slumping is done.
The curved mirrors used for observing traffic (at alleys, etc.) are quite
weather resistant, so what do you need more.
If the glass has stainless steel in the middle, it won't slump. Aluminium
will melt and flow. Laminated glass has plastic in the middle which is
destroyed long before the glass slumps. Silver is always applied on one
side.

I'd like a 'silvered' layer in the middle, for protection, and was referring
to the stainless/aluminium as an alternative.

Mirroring after slumping is awkward, as I'd like it to survive 10-20 years
outside without getting pinholes even when rained on.

It's for a decorative photovolataic collector.

Thanks for the comments.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
"Don't count the humans out until the last one is dead and you have
hacked its body to bits and eaten it" -- John Ringo.

Ian Stirling wrote:

I'd like a 'silvered' layer in the middle, for protection, and was referring
to the stainless/aluminium as an alternative.

Mirroring after slumping is awkward, as I'd like it to survive 10-20 years
outside without getting pinholes even when rained on.

Another option is chrome-plated steel (or copper, bronze, etc., or
perhaps even plastic or glass). If done well with a heavy plating,
that would keep its mirror finish with less maintenance than aluminum
(and maybe less than stainless as well). But chrome plating is not a
do-it-yourself operation, if that's a concern.

Or how about applying a good automotive finish to the back of your
slumped mirrored-on-one-side glass (assuming that the slumping process
doesn't degrade or destroy the mirror coating)? You would probably
need to seal the edges somehow, unless you used a clear coat and
covered the whole mirror (front, back, and edges).

It's for a decorative photovolataic collector.

Are you talking about a simple 2-D curve (like a trough) or a compound
curve (like a paraboloid)? If the latter, will it have drain holes, or
is it going to be positioned or sheltered such that it doesn't collect
water? Otherwise your photovoltaic collector may turn into a shiny
birdbath if it's in a region that gets much rain!

Bert

Bert wrote:
Ian Stirling wrote:

I'd like a 'silvered' layer in the middle, for protection, and was referring
to the stainless/aluminium as an alternative.

Mirroring after slumping is awkward, as I'd like it to survive 10-20 years
outside without getting pinholes even when rained on.

Another option is chrome-plated steel (or copper, bronze, etc., or
perhaps even plastic or glass). If done well with a heavy plating,
that would keep its mirror finish with less maintenance than aluminum
(and maybe less than stainless as well). But chrome plating is not a
do-it-yourself operation, if that's a concern.

Or how about applying a good automotive finish to the back of your
slumped mirrored-on-one-side glass (assuming that the slumping process
doesn't degrade or destroy the mirror coating)? You would probably
need to seal the edges somehow, unless you used a clear coat and
covered the whole mirror (front, back, and edges).

I suspect it's likely that unless it's done in an inert/hydrogen atmosphere,
a normal silvered mirror can't be slumped.

I wonder if it would work, if it's done in a reducing furnace.

Anyway, it could be silvered later.


It's for a decorative photovolataic collector.

Are you talking about a simple 2-D curve (like a trough) or a compound
curve (like a paraboloid)? If the latter, will it have drain holes, or
is it going to be positioned or sheltered such that it doesn't collect
water? Otherwise your photovoltaic collector may turn into a shiny
birdbath if it's in a region that gets much rain!

Compound curve, and it will not collect water, due to the design.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
Paranoia: A game for the whole family, and anyone else who might be watching.

Ian Stirling wrote:


I suspect it's likely that unless it's done in an inert/hydrogen atmosphere,
a normal silvered mirror can't be slumped.

I wonder if it would work, if it's done in a reducing furnace.

Anyway, it could be silvered later.

Slumping in an inert/hydrogen atmosphere? Sounds interesting. I'd go
heavy on the inert and light on the hydrogen.
--
Jack


http://photos.yahoo.com/bc/xmissionbobo/

nJb wrote:
Ian Stirling wrote:


I suspect it's likely that unless it's done in an inert/hydrogen atmosphere,
a normal silvered mirror can't be slumped.

I wonder if it would work, if it's done in a reducing furnace.

Anyway, it could be silvered later.

Slumping in an inert/hydrogen atmosphere? Sounds interesting. I'd go
heavy on the inert and light on the hydrogen.

Well, it depends if you like bangs or not
On the plus side, you could probably just sprinkle silver oxide on the
surface of the glass, put it in the furnace, and out comes a mirror.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
Two fish in a tank: one says to the other, "you know how to drive this thing??"