Re: ATM About making a glass blank

["Bob May" <bobmay@nethere.com>]

Kind of depends upon what tools you have at hand.  If you have a large kiln
available to you, you can indeed cast your own glass.  I'd suggest that you
consider using a particular brand of bottle to minimize the necessity of
mixing the glass too much before letting it cool.
Aside from actually melting the glass, you can use several disks of glass,
slumping and fusing them one at a time into a thicker piece of glass.
Then there is the buildup of a large mirror from a front and rear plates and
a bunch of ribs to hold the two apart.  This is a bit more interesting as
you want to fuse the glass together but not leave it up that hot long enough
to do much slumping of the glass.  You also end up with a piece of glass in
this system that may be a bit more sensitive to heating as the ribs may
decide not to support the top and bottom apart due to the stressing of the
glass parts.
The most difficult would be the creation of the glass from the silica
pebbles as this needs fairly clean silica to keep from getting impurities
into the glass, the ability to get the resulting glass hot enough to where
the bubbles all float to the surface and pop in a decently short timeframe
and make sure that the glass just isn't a froth of airbubbles which happen
when the glass tries to melt from the top down.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net