Glass Forge

The Glass Forge is an industrial building that produces Molten Glass, which can then be cooled into Glass. Its output is extremely hot, but the total heat released by each batch is relatively small compared with many other industrial buildings, so the main challenge is not the forge itself but safely handling the molten product.

Glass is used to construct Window Tile, so the forge is a key step in unlocking transparent building materials. Once produced, Molten Glass has a freezing point of 1126 °C and will solidify almost immediately when exposed to ordinary temperatures. That makes transport and cooling the most important part of any glass production setup.

A safe output line should use Insulated Liquid Pipe and be kept as short as possible. The molten contents are treated as occupying the bottom-middle tile of the forge for heat transfer, so that tile should also be insulated. If enough thermal conductivity is present around the forge or along the pipe, the glass can cool to its freezing point while still inside the building, then freeze and crack the pipe as soon as it exits. Even a small amount of water on the floor can cause the pipe to burst, so the workspace should be kept completely dry.

Because Molten Glass carries a very high temperature but not much heat mass, it is usually practical to simply drop it from a liquid vent onto the floor and let it cool there. In many cases, the heat load is comparable to other industrial machinery rather than something uniquely dangerous. That said, nearby materials with low melting points, such as lead, can still be a problem if they share the cooling area with fresh glass.

Dropping Molten Glass into water is an effective way to freeze it quickly. This can be used intentionally when fast solidification is desired. Another option is to release the molten glass through a conduit and let it lose heat rapidly in transit; when done correctly, the pipe can be emptied before the contents have time to transform in a way that damages the line.

A few practical points matter when planning a forge:

• Use Insulated Liquid Pipe for the output, and keep it short.
• Keep the bottom-middle tile of the forge insulated.
• Do not allow water or other liquids near the output path.
• Avoid letting the glass cool inside regular liquid piping.
• If you need solid Glass fast, water is a reliable quenching method.

In heat terms, the forge can even become a net heat sink when fed sufficiently hot Sand, and producing Glass from a cooling medium can remove a substantial amount of input heat. When run continuously, however, the overall process still releases a significant amount of heat, so the forge should be placed with the rest of an industrial cooling plan in mind.