Friday Night Fusing Clinic
March 09, 2007 - Vitrograph
The purpose of the Vitrograph is to use a small “Hot Box” kiln to create irregular stringers.
Materials
- small kiln with removable top and bottom
- 1 sq ft. fibreboard or vermiculite board, with a small hole cut in the middle
- 2 aluminum ladders and 2 wood or steel beams or 1 folding, adjustable aluminum ladder
- 1 small non-glazed terra cotta flower pot
- small amount of compatible glass and/or frit
- needle-nose pliers, shears, gloves & safety glasses
- metal cookie tray
Cut out a piece of 1 fibreboard so that it will fit snugly between 2 of the rungs, and then test fit the kiln, placing it on top of the fibreboard. Check that you have easy access to the power switch and also to the underside of the kiln. Make sure that ladder(s) are secured and will not move.
Cut a hole in the middle of the fibreboard using the hole in a small terra cotta pot as a guide. Use any size flower pot with a 1/2” hole. Ensure that pot will fit in the kiln with the lid on. Fill the pot with a single colour of glass chunks or frit. A more advanced method is to cut out small spacers of cardboard and fit into the pot, creating 2 or more sections. Remove the cardboard before firing of course Fill each section with a different colour of glass. Place the glass filled pot on the fibreboard, lining up the hole in the bottom of the pot with the hole in the fibreboard. Place the body of the kiln back over the fibreboard and the glass filled pot. Place the base of the kiln on the top of the kiln and heat to 1800°. Use the base as most lids now come with a window. As the kiln is so elevated, and the window allows a slight heat loss, you want to use the solid base as the lid in this situation.
Place a metal cookie sheet on the floor below the kiln to catch the stringers. DO NOT try this over a carpeted, linoleum or hardwood floor A ceramic tile or concrete floor is ideal and safe. When the kiln has reached 1800°, watch the hole on the underside of the fibreboard for the glass to start bulging out. When the glass does start to come out, reduce power on the kiln to the 5 or 4 setting.
Wear safety glasses and gloves at all times when working with a vitrograph. Use pliers to manipulate the molten glass as it emerges through the hole in the fibre board. Use two pairs of pliers to shape stringers, if desired. Use shears to cut the stringers to desired lengths. Allow to drop onto metal cookie sheet . When the glass appears to be a grayish or dull transparent colour, the glass in the pot has run out. Turn the kiln off and allow to cool.
You will be able to use one flower pot a number of times. You can change colours if you want, but there might be some colour contamination.
