Here is a 350mm diameter tube during production through one of the larger lathes that we have in the production area.
The heat required is needed to get the Quartz glass up to 1750 to 1800°C working temperature.
The Glass Blower is getting the tube end ready for creating a flattened base as opposed to a straight cut end.
Working the ends
The tool the Glass Blower is using is a carbon plate. This tool is named a ‘paddle’, the carbon is highly heat resistant and carbon is the main material used to shape the quartz glass at high temperature. You can clearly see the square shaped paddle which is pressing up against the tube end as the quartz glass is becoming formed into the desired profile.