Chunk Casting

Chunks of glass are placed in a mold, then heated in a kiln until the glass softens and flows downward to gradually fill the mold. Popular with contemporary artists, this method avoids the need for a giant melting furnace filled with molten glass.

Category:

Education

Tags:

• CorningMuseumofGlass
• corning
• glass
• museum
• newyork
• NY
• glassmaking
• makeglass
• glassmaking processes
• 62.3.132
• 94.3.100
• 2004.3.10
• Casting

[JohnnyDesaint]

GOOD VID.COULD THIS PROCESS BE USED TO MAKE A CLEAR PLASTIC CAR LENS?

[corningmuseumofglass]

@JohnnyDesaint The type of mold pictured is referred to as an open face mold. You could have one side of the glass be almost any shape, but the backside, the upward facing side, will always be flat. casting a fully 3-d object is possible, but much more difficult and complex.

[corningmuseumofglass]

Crushed and /or broken glass is usable, but will tend to trap more bubbles. More important is the type of glass, and if you are thinking about recycled bottle or jar glass, then you may run into many problems, such as incopatibility, devitrification and because of having to fire to a higher temperature, mold breakage and surface to mold adhesion.

[tycotyrann]

how do you do the mold? Can you reuse it?

[corningmuseumofglass]

The mold is made from plaster and silica and it is not reusable.

[crushsatan]

@corningmuseumofglass

is silica necessary?

[corningmuseumofglass]

@crushsatan - Yes, the silica makes the mold more heat tolerant and help to keep the mold from falling apart as the temperature climbs. Too much can be bad also, as it fuses and ticks to the glass as it melts into the form. Half plaster, half silica is a normal simple mold formula.

[JohnnyDesaint]

@corningmuseumofglass THANX ILL DO MORE RESEARCH....I WANT TO KNOW HOW MY CLEAR DRINKING PLASTIC CUP IS MADE.

[tizbrin]

Is it possible to use crushed and broken glass instead of chunks?

[crushsatan]

@corningmuseumofglass can I use just any silica sand I pick up from home depot or what have you?

[crushsatan]

@corningmuseumofglass

thanks much

[lozerkidkp]

@dvaders2 1400 C