From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Casting Lead Sheet
Date: Tue, 05 Oct 1999 23:25:50 GMT

The "Float Glass" process was developed by Pilkingtons in the UK.  The objective
of using tin..as opposed to sodium, lead, sulphur or whatever, is that it:

Being liquid, imparts a dead flat surface to the underside of the glass.

Being hot, it keeps the glass hot and fluid long enough for top surface
imperfections to level out.

It remains liquid at a temperature BELOW that at which glass becomes rigid
enough to cut, handle and remove...this is a continuous process..molten glass
being metered (doctored) onto the surface of a LOOOONG tank of molten tin,
cooling as it moves allong and being removed in solid, cut lengths of top grade
plate glass at the other end.

Tin is non toxic and (relatively) non reactive nor does it vaporise readily at
the temperatures involved.

It is relatively inexpensive.

The Float glass process was the worlds first CONTINUOUS plate glass process and
was licensed all over the world by Pilkingtons.

The plants where float glass is made are the hottest places on the face of the
earth!!

teenut

T Mulone wrote:

> You don't want to chil the glass when you float it on the metal or it will
> crack. On the other hand, You don't want to add heat to the already molten
> glass. I suspect that the melting point of tin is a good match for the hot
> glass.
> Tim

From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Casting Lead Sheet
Date: Wed, 06 Oct 1999 03:51:02 GMT

It is a moot point!

It seems most of the melt shops I was in, were wide open to the elements and (In
Winter) had howling gales running through. Seemed to spend half the time
dripping with sweat and half the time freezing!!  ;^)

I guess I also spent more time in the steel mills during shutdowns for repair or
maintainence.

teenut

Jesse Brennan wrote:

> >The plants where float glass is made are the hottest places on the face
> >of the earth!!
>
> NO way the hottest They are quite comfortable compared to a steel
> meltshop floor Or any place steel or iron is poured intom molds. I've
> been alongside 10 of the US floats. plus a numnber of steel melt shops.
> Jesse