Heather KonschuhHK




Photography: June Jenner


Blowing Glass

Each piece begins with clear molten glass. This glass has been melted in a furnace at temperatures over 2000 degrees F (1100 degrees C). The glass is workable and plastic at temperatures around 1000 degrees F (550 degrees C).

The tip of the blowpipe is first preheated and then dipped in the molten glass in the furnace. The clear molten glass is gathered onto the blowpipe.

Different metals are added to the glass to colour it. For example; gold is added to make red. These colours are commonly picked up in a glass 'bar' form or rolled on with glass 'frit' or 'powder'. Stringers, bits, wraps and murrini are other ways to alter the colour appearance of your piece.

Tools are very important in the glass making process. Heather uses jacks, tweezers, wooden blocks, a bench, paddles, marvers, wet newspaper, diamond shears, straight shears and graphite. Glass blowing can be fast paced; timed flashes in the glory hole, changing the angle of the pipe and handling the tools during crucial moments help determine the outcome of the piece. The blow pipe holding the molten glass must be consistently turning or the hot glass will fall off centre.

Temperature is key to successful glasswork. There are moments to work with the glass in its cold state as it is very fragile and there are moments that its needs to be heated extremely hot.

Every glass piece has to be slowly cooled in an annealer over night. On a molecular level, the properties of glass have sporatic molecules which need time to expand and contract in order to reduce thermal stress. Glass needs the appropriate soak times and temperatures in order to come down to room temperature. If cooled too quickly the glass will crack and possibly explode. Blown glass work needs to be transferred to another pipe, called the punty, in order to finalize both ends of the piece. Each blown glass piece is left with a scar on the bottom from the punty or transfer point.

Once annealed, the scar is taken off through cold working processes. Equipment such as diamond pads, lathes, diamond wet saws, belt sanders and sandblasters are used to cold work the glass into its final state.