Flat Glass Prototypes

[Planet Glass]

Below is a picture of the flat glass we produced in the hot shop last Thursday.

This one was heated on a pastorelli and flattened to a very uniform 3mm with a metal roller. Very easy to do, but some drawbacks:

(1) kiln wash fused to underside, making it frosty
(2) small indentation between each cane remains

http://the-glass-artist.com/images/zanfirico-flatglass1.jpg

See frosted reverse:
http://the-glass-artist.com/images/zanfirico-flatglass2.jpg


We also did some flat glass with a cane pick up (not rollup!) on clear glass. The result is much more lively, but the glass was much too thick. 8hr annealing was not sufficient as the piece cracked...

http://the-glass-artist.com/images/zanfirico-flatglass4.jpg

http://the-glass-artist.com/images/zanfirico-flatglass3.jpg

My conclusion:

As labor intensive as it's going to be, the best result would combine (1) blowing the cane pickup, (2) after opening up and flattening the cylinder, placing it on a kiln shelf and re-heating it on the pastorelli, and rolling it flat with that big metal cylinder we have at Espace Verre, and (3) polishing the frosted underside off, cold.

I swear it I would sell that stuff I wouldn't make a profit under $300 a piece.

Many thanks to Bruno Andrus (http://brunoandrus.com) and Karina Guévin for valuable advice and technical skill.

[Planet Glass]

Today I'll be visiting a blacksmith and picking up an iron cylinder and two iron "sticks" of a 5mm thickness. I can use the cylinder to roll the hot glass like dough, and the sticks will insure a uniform thickness.

[bert weiss]

Once at Haystack School, we ladled molten glass on an inch thick marver. We had clamped some flat bar on the edge of the marver, and used some black iron pipe to roll out sheets. It worked pretty slick, but the marver warped. A lot!

My blower pals swear that a warped marver is more useful than a flat one.

[Planet Glass]

I'm glad to know that it worked! I won't be ladling hot glass from the furnace, I'd be shocked if the marver warps.

But I have a question.

Once you have the flattened glass on the marver, do you put back on a pastorelli and flash it before you put it in the annealer, or just put it in the annealer?

And how do you handle the sheet into the annealer? A couple of people with mitts?

[Planet Glass]

Persevering with this experiment, I tried with with the iron rolling pin but the results were yucky, you be the judge (note that I used crappy zanfirico to start with because I didn't want to waste good ones):

http://forums.the-glass-artist.com/picture.php?albumid=68&pictureid=477



Next we tried two ways. We picked up the zanfirico cane on a glass bubble (the two bottles on the left), but the zanfirico blew "muddy" and looked overheated. We also picked up the zanfirico from the pastorelli directly on the cane, and added clear glass to the surface. The pattern is much better defined.

http://forums.the-glass-artist.com/picture.php?albumid=68&pictureid=476

The bottles will be sawed in half and flattened in a kiln.

A clamshell kiln is available which will allow us to manipulate the glass as it slumps to make sure it flattens properly.

[Planet Glass]

UPDATE:

http://forums.the-glass-artist.com/album.php?albumid=68