How to Cut, Score and Break Glass
Glass can be cut into strips, geometric shapes, circles, ovals, curves and with a glass saw, almost any shape.
Some Things to Keep in Mind
• Warm glass (glass at room temperature) cuts easier than cold glass
• Work surface needs to be flat
• Score on the smooth side of glass rather than on the textured side
• Hold glass cutter in a vertical position as you would a pen or pencil
• Don't use excessive pressure. Too deep of a score can result in a bad break
• For protection, it's a good idea to wear glasses or another type of eye protection
Straight Cuts
When making a straight score, start scoring the glass from the point farthest from your body and pull the glass cutter towards you. Once a score line is made, use running pliers (if strip is at least 1" wide) by placing the running pliers centered on the score line and gently squeeze the handles. You will hear a slight cracking noise and see the glass separate along the score line. Or, hold the stained glass sheet over an edge of a table with the score line slightly overhanging the edge. Use breaking or grozier pliers and apply gentle pressure in a downward motion along the score line. This can also be done with your hands using the same downward motion. Practice will make for perfection, soon.
Curve Cuts
To make a curved cut, use the glass cutter to cut off sections one at a time. This allows you to work into the curve. Glass likes straight lines or lines with gentle bends. If the shape has irregularities or small projections, these are easily removed with a nipper or glass grinder. In other words, don't rush the cut especially if it is an inside curve. Just chip away at it a little bit at a time.
Cutting Circles
Score the glass in the shape and size of the desired circle. Use a permanent marker to place a dot where you start scoring to avoid going over the starting point. Next, place the scored line side of the glass down on a piece of corrugated cardboard. Use light pressure and press along the score line until you see it run the circle. Then, turn the glass over to the side you first scored on and score several tangent cuts radiating out from the circle. Finally, break each tangent score line with breaking pliers. The circle should cut clean without any jagged edges.
How To Avoid Common Problems
• Cutter wheel wears out quickly – Lift your cutter up instead of sliding it off the edge of the glass or cut on a surface covered with vinyl or carpet
• Bad breaks after scoring – Too much pressure was applied on the glass cutter
• Score line looks like dotted line – Cutter wheel is dull and needs to be replaced
Be sure to turn your pattern template over when you are tracing your pattern onto the backside of the glass where it smoother. Failure to do this will end up in wasted glass and lots of wasted time, not to mention frustration.
Some Things to Keep in Mind
• Warm glass (glass at room temperature) cuts easier than cold glass
• Work surface needs to be flat
• Score on the smooth side of glass rather than on the textured side
• Hold glass cutter in a vertical position as you would a pen or pencil
• Don't use excessive pressure. Too deep of a score can result in a bad break
• For protection, it's a good idea to wear glasses or another type of eye protection
Straight Cuts
When making a straight score, start scoring the glass from the point farthest from your body and pull the glass cutter towards you. Once a score line is made, use running pliers (if strip is at least 1" wide) by placing the running pliers centered on the score line and gently squeeze the handles. You will hear a slight cracking noise and see the glass separate along the score line. Or, hold the stained glass sheet over an edge of a table with the score line slightly overhanging the edge. Use breaking or grozier pliers and apply gentle pressure in a downward motion along the score line. This can also be done with your hands using the same downward motion. Practice will make for perfection, soon.
Curve Cuts
To make a curved cut, use the glass cutter to cut off sections one at a time. This allows you to work into the curve. Glass likes straight lines or lines with gentle bends. If the shape has irregularities or small projections, these are easily removed with a nipper or glass grinder. In other words, don't rush the cut especially if it is an inside curve. Just chip away at it a little bit at a time.
Cutting Circles
Score the glass in the shape and size of the desired circle. Use a permanent marker to place a dot where you start scoring to avoid going over the starting point. Next, place the scored line side of the glass down on a piece of corrugated cardboard. Use light pressure and press along the score line until you see it run the circle. Then, turn the glass over to the side you first scored on and score several tangent cuts radiating out from the circle. Finally, break each tangent score line with breaking pliers. The circle should cut clean without any jagged edges.
How To Avoid Common Problems
• Cutter wheel wears out quickly – Lift your cutter up instead of sliding it off the edge of the glass or cut on a surface covered with vinyl or carpet
• Bad breaks after scoring – Too much pressure was applied on the glass cutter
• Score line looks like dotted line – Cutter wheel is dull and needs to be replaced
Be sure to turn your pattern template over when you are tracing your pattern onto the backside of the glass where it smoother. Failure to do this will end up in wasted glass and lots of wasted time, not to mention frustration.