How to Cut Circles

by Brooks Gardner
(Mebane, NC)

I have seen many different methods for cutting a circle, but I have never seen a real evaluation of the various tools and methods.

Is someone brave enough to discuss this subject. I have tools that are absolutely useless for this proceedure.

Answer
Hi Brooks,

Cutting circles can be easy or hard, depending on the technique you use. This tutorial from Spectrum Glass Company demonstrates the correct way to cut a circle and run the score. This is the way I do it.

Over the years I have used many different circle cutters. I never found one that was impossible to use. Some of them do have a learning curve, but once you've figured out the best way to use the particular tool, they all work.

In my home studio I use the Morton Portable Workshop circle cutter for cutting smaller circles, and the Inland strip and circle cutter for larger circles. Both of those tools work well.

The only problem with the Inland (and the Glastar which is very similar to the Inland) is that they slip because the suction cup doesn't hold very well, especially on textured glass. I have overcome that by using the "play dough" type material, used to attach posters to a wall. I put a small ball of it at four points on the suction cup, then press the cup on the glass. It works like a charm, and can be used over and over.

In my opinion, the Silberschnitt Pro Circle Cutter is top of the line. It will cut circles 2 1/2 to 24 inches. For smaller circles the Fletcher Lens Cutter does a great job. Both of these are tools will last you a lifetime. They are precision made and expensive. If you only cut the occasional circle, they are an expensive item to store away for the few times they'd get used. We used them in our production studio when we were cutting a lot of circles, but now that our business is mainly repairs and restorations, we don't need them any more.

Circles can also be cut accurately, by hand. The technique, in a nut shell, is to draw the circle on the glass. Start the score, then stop moving the cutter, but hold it down on the glass like you would if you were making a score. Now you will turn the glass with your other hand instead of trying to move the cutter all the way around the circle. Make sure you keep the cutter on the line. If the glass is on a piece of paper, it will turn quite easily. Stop scoring as soon as you get back to the starting point. Turn the glass over and run the score as shown in the Spectrum tutorial. If I'm in a hurry, and don't want to get out a circle cutter, I use this technique.

If anyone reading this has any circle cutter/cutting experiences to tell us about, please use the comments section below.