Larbert High School

Advanced Higher Art and Photography

The pupils had just completed their installation project,which were based on their sketchbook research and developments, and I was given the opportunity to introduce them to casting with glass.

I demonstrated the process of casting using the investment method and, in this case, we used clay forms, a plaster mix and System 96 glass.

The pupils created their clay forms to a specific size that would fit within a set mould shape.  This is important as the depth of the glass influences the kiln firing schedule and we wanted to keep this short and simple.  We used recycled plastic food containers for the mould frames; these are easy to get and can be reused several times and reduce waste.

Each of the damp clay forms were weighed and this weight then informed the calculation to establish the volume of glass required for each casting.

The pupils selected their glass colours and then prepared their glass into small pieces which allowed easy loading of the moulds.  The glass always looks too much when loaded however it soon pours into the mould and fills all of the voids.  In this instance we incorporated a small overflow area at the top of the forms to accommodate this process.

Once the pieces were fired the casts were diveted from their moulds, washed and then polished to create a lovely finish.

If I said that there was a lot of excitement when the pieces were being divested then that would be an understatement; the wonder of releasing these beautiful glass artefacts from the fired plaster is always magical and I think the pupils, even the cool ones, couldn't contain their excitement.  Well done all of you!