Sunday, 11 February 2018

Glass Cutting Surfaces

There are several considerations about your surface for cutting glass.

Make sure you are putting the glass on a flat surface. If the surface is uneven, it will give difficulties in scoring and breaking.  This means that large sheet timber is an excellent surface.  These boards need to be securely screwed down to the bench structure to avoid any warping.

There is some advantage to having a slightly cushioned cutting surface. This will help accommodate glass with a lot of texture and those sheets that have slight curves in them. 

In this example the user has placed corrugated cardboard under the glass for cushioning, but with a hard surface underneath

Consider ease of cleaning.  As you score and break glass, small shards will be left on the cutting surface.  The tell-tale squeaks as you move the glass indicate there is other glass under the sheet. These shards and any other small almost invisible things under your glass can promote unwanted breaks. Also, if there is glass or other grit on the surface, it may scratch the glass. So make sure you brush the cutting surface clean frequently.

An example of a ready made cutting bench.  It has the advantage of being easy to clean and compact when not in use. 

Think about the size of sheets you will be cutting.  Large sheets often have minor imperfections in texture, or some bowing.  These benefit from a slightly cushioned surface. It also allows the sheets to be put down onto the surface with more confidence that it will not break in contact with the bench top.  But if you are cutting mostly smaller sheets, they benefit from a smooth hard surface to support the whole of the sheet especially when cutting long thin or curved pieces.

An example of a large cutting bench with composition board top surface

Some of the materials used are sheet boards (such as marine plywood, MDF, and other composition boards), short pile carpets,  thin rubber or foam sheets, dining table protectors and pin boards. 

All these are useful for cutting each with advantages and disadvantages.
  • Carpets and foam can trap shards of glass, so have to be cleaned very carefully to avoid retaining sharp glass within the pile or foam.
  • Smooth, wipe-able surfaces avoid trapping glass, but can be slippery. Choose one with a non-slip surface.
  • A slightly cushioned surface is good for large sheets
  • Smaller sheets of glass are best cut on smooth hard surfaces, providing support for all of the glass sheet.
You can also consider, as in the example above, the use of different cutting surfaces on top of the larger smooth and hard surface.  This allows adaptation to the needs of your glass without duplicating surfaces.

Before scoring, clean the glass on both sides, to ensure any sounds you hear when moving the glass relates to glass shrds on the bench rather than grit on the glass.  At the very least, clean along the cut line, as this makes the action of the cutter smoother. The grit on the glass actually interrupts the action of the wheel, so you get a staccato effect in the score line.