Sculptglass

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FREQUENTLY ASKED QUESTIONS & ANSWERS 

WHAT IS THE GLASS MADE FROM?

The glass I use is a is a Soda based, lead free glass.  Having no lead means you have to work faster and hotter, but it is much better for the environment.  The glass is mainly made from a mix of silica sand, Sodium Carbonate (like washing soda) and Calcium Carbonate (lime stone).  A few other special ingredients are added such as Barium Carbonate to give the glass a greater sparkle.  The mix is melted overnight in the furnace at just over 1200'C, it transforms it into beautifully clear molten glass by morning.

HOW HOT IS THE GLASS?

While working the glass, the furnace is between 1060 to 1070 degrees centigrade.  This temperature gives the glass a thin honey like consistency.  As soon as the glass is removed from the furnace it cools very rapidly, becoming thicker until its surface hardens.  I must work quickly and will often reheat the piece, in the furnace, the glory hole or by using hot torches.  This softens the glass and allows more time for it to be worked.  Some pieces are made from one gather of glass, while others are built up over time.

HOW DO YOU GET THE COLOUR IN THE WORK?

The colour is actually coloured glass powder, glass chips or glass rods.  22-Carat gold and Sterling silver leaf can also be placed on the glass.  The molten glass can be rolled into the colours, with different layers blending together to create rich and subtle effects. 

The combinations and techniques are endless; pieces can be cold worked and sandblasted to reveal other coloured layers of glass%u2026

DO YOU BURN YOURSELF A LOT?

The radiant heat from the glass can be quite surprising, but careful use of shielding tools, protective clothing and simple acts such as wetting your hands before getting close to the piece can limit the amount of pain endured! 

WHY DO YOU PUT THE WORK IN THE OVEN?

If I didn't, it would crack or explode! Once finished, it is allowed to cool until it has almost lost it%u2019s red glow.  It is then cracked off into the annealing oven, which is held at a constant 500'c.  Depending on the thickness of the piece it must be held at this temperature for a period of time until its temperature is the same throughout.  It can then be cooled down very slowly overnight.  This relieves the stresses in the work and anneals it.

HOW ARE THE PIECES FINISHED?

Once cooled, a piece can be cold worked with special diamond tools, polished with powders and even sandblasted to create the finishes required.  This time can often take far longer than the time it took to make the piece when molten!  Most large pieces are also signed and dated.

HOW LONG HAVE YOU BEEN DOING THIS?

My love of art began in childhood and lead me to study Fine Art Sculpture to Masters Level in the Midlands. After sculpting clay, stone and wood, I cast some of my figurative sculptures into glass.  I built this glassworks in 2002.  Since then, via a process of drawing and experimenting with the glass I continue to develop a range of sculptures in a material that hints at endless possibilities. 

HOW ENVIRONMENTALY FRIENDLY ARE YOU?

The Furnace has a specially designed heat exchanger which recycles the waste heat and this reduces the gas bill for the furnace by 25%.   The glass I use is a lead free glass made of a mix of recycled glass and new batch. 90% of the gallery is lit with very efficient LEDs and timers are used for evening display.  All our packaging comes from environmentally friendly sources such as Green Island Packaging.  Our left over glass is used to make recycled glass awards so nothing is wasted.  The furnace and ovens are now carbon neutral.  For more information please see our environmental policy page.