Hello, my name is Phillip McKee of McKee Stained Glass and right now I am showing you how to score and break an outside curve. There are two types of curves in stained glass and I can demonstrate them both with this one curve. If you are cutting and keeping the glass, bound by this curve and throwing away this glass, then what you are cutting is an outside curve because the glass being thrown away is outside of the curve. The easiest way to cut and score an outside curve is using tangents. By that I mean, you first score and break this straight line, then you move on and score and break another straight line, followed by a third and a fourth. The more tangents you use, the closer your curve will be to perfect.

You then grind off the excess glass. So, let us cut this outside curve, since we are not actually keeping these straight lines, we are grinding them to occur, you do not need to use your L-Square or ruler. However, you do need to remember before you begin to score to use an important piece of safety equipment, your safety goggles. Always wear your safety goggles before you begin scoring and breaking glass. So, we do our first score and you want to make sure you do not run off the glass like I just did, it can damage your cutting wheel. Once we have got our lines scored, we have get our running pliers and we squeeze. Place your excess glass aside, we do our second score, see if it will fit, if it will fit, we use our running pliers, since on either side it will not fit, we will use our Breaker/Grozer.

Small pieces of glass can be thrown away, either have a trash can nearby or keep a small bucket near you and use that as your scrap glass collector. It is often a good idea to have a small bucket nearby because you can use your scrap glass later, either for other projects or in mosaics. With our final score, we have a piece that roughly approximates an outside curve. We will then be able to grind this down and turn it into a perfect curve. There is one other way to do an outside curve especially if it is a gently outside curve and by that I mean one that does not have too much of a curve to it. That is a special technique called a Pinch Break. We take our cutters, we score along the curve all the way around it. Pinch with your thumb and forefinger at the apex or highest point of the curve.

Pinch it tightly, take your running pliers and we squeeze. If you have done it right, your curve will break in one single score. That is how we break an outside curve, next we will learn how to break an inside curve.