Glass combing is a very stimulating furnace-forming process. Glass is controlled by heating it to a soft point and then using a long stainless steel tool to scrape off the substance. 

This action is usually done with a drawing movement. Arrange the cups and items needed for this process. Make sure all glass has an equivalent COE (Coefficient of Expansion). You can also check for the best COE glass via the web. 

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The jar should be clean and dry before you begin. Fill the glass several layers thick or lay it horizontally and glue it together. Different shades react differently to high temperatures. Write down everything that happened during the method.

A pot of tap water should be nearby for dipping the hot paddle after rowing the cup. Make sure the container is large enough to accommodate and support the rack if needed.

When the jar is heated to about 1250 degrees Fahrenheit, let the pieces soak at approximate temperature for about 20 minutes before heating further. 

It should reach a temperature of around 1640 degrees Fahrenheit, depending on the COE of your glass. Once the mugs have reached their melting point, turn off the oven. When playing in full protective clothing, open the oven lid. Just brush the top cover of the material, as further digging can interfere with flushing the hob under the glass.

This sweep must be done quickly before the glass cools down. If the fabric begins to cool earlier than desired, cover the oven and turn it back on to heat the jars.