Perfect Stained Glass Cutting
Learn how to make stained glass, starting with a comprehensive guide to glass cutting.
Glass Cutting Made Easy
When you have measured up and you have your cutline, you’re ready to cut. The glass is cut to shape on top of the cutline and is cut in two stages.
- First you have to make a score line with the cutter, which starts a fracture.
- The second stage is to deepen this fracture by tapping or by hand, which causes the glass to split.
What supplies you need
Glass cutter, grozing pliers, dustpan and brush, your cutline and glass.
Buy an oil-filled cutter –like this Pistol-grip cutter from Toyo, some of my students swear by them. They’re more expensive, but infinitely superior in quality and you don’t have to keep dipping the wheel in oil as you go.
How to cut glass
Practice holding the cutting tool between your index and middle fingers, with your thumb at the back. If you don’t find this easy, try holding it like a pen.
To make a score line, hold the cutting tool upright with the screw in front of you and draw the steel wheel across the surface of the glass. It should make a nice swishing sound.
You have to go all the way from one side of the glass to the other, you can’t stop half way, so make sure you can reach the end of the piece of glass!
I find it easier to cut away from me if I’m following a cut line, as that way I can see where the line is without my hand getting in the way.
Get the hang of how much pressure to apply by practicing on some scrap glass, and remember that different types of glass cuts and breaks differently.
- If you press too hard you’ll leave a white residue and the glass won’t break cleanly
- if you don’t press hard enough the glass won’t break.
- Cut on the flat, non-textured side if you’re using art glass.
Never go over a cut a second time – it will damage your cutter.
Now for the breaking. If it’s a straight line, place your thumbs parallel to the score line and apply pressure whilst twisting your wrists outwards. The glass should split easily.
If you are cutting thicker glass, or a thin bit of glass you can use Cut Running Pliers – a specialist glass tool for cutting glass - to apply even pressure to either side of the score line.
If the glass doesn’t come apart, tap on the underside of the score line with the ball end of the glass cutter to open up the score line. You will get used to hearing the changing sound of the glass when it is ready to come apart.
To cut deep curves, first make a confident score line along your desired shape...
...and then a series of small incisions which are either tapped out or grozed away bit by bit with grozing pliers.
Remember, if you're not accurate with your cutting, you will find every stage of making your stained glass panel harder and harder, so take time to get the hang of it properly now.
