Your hobby should be a relaxing time for you to escape your day to day stress. When you're working on your stained glass project, you should love what you're doing and not be frustrated by having to re-cut pieces or be worried about wasting glass because something broke the wrong way. Building your glass cutting skills will help a lot to ease the stress.
All too often, there is a hesitance to cutting glass and I can understand why. From the time we're little, we're taught to fear it. "Oh, don't touch that! You might break it." And now all of a sudden as stained glass hobbyists you're expected to just get over that fear? Put on a brave face and march proudly forward? It's really not that easy! I know. I started out that way too. But just as you were taught to fear breaking glass, you can also learn to get comfortable with it and actually enjoy it.
Any glass crafter knows that cutting glass is nothing like cutting paper. Paper cutting allows you to start wherever you want and finish wherever you want. To cut a circle, you simply pick a place to start and you can cut it out all in one shot. Glass, on the other hand can be fickle even if you understand the principles of why glass breaks the way it does.
Glass cutters are made and used more like a wedge than a knife. By running the carbide cutting wheel across the smooth surface of the glass, with the right amount of pressure, a “score” is formed.
The score is meant to be more or less, a path that we use to direct the glass where we want it to break. But being the stubborn character that glass can be, it likes to set the rules and will only “behave” nicely, when we do things the way it wants us to. Knowing these rules can make cutting glass so much easier.
Build consistency in your glass cutting
I’ll start by outlining these strategies from the beginning of the process. You may think that some items on this list aren’t directly related to using the cutter, so they aren’t really all that important when it comes to cutting glass. That may in part be true to the fundamentals of glass cutting. But if you’re looking to improve your consistency, these seemingly basic things can make a world of difference.
1. Start with clean glass
Now I’m just as guilty as the next person for having pulled a sheet of glass out of the rack and not worried about cleaning it. But if you’ve had glass around for quite a number of years, you’ll notice that it actually develops a greasy, grimy film on it despite being stored away from your kitchen.
If you want to ensure the best chance of consistent contact of the cutter wheel on the glass, you’re better off to clean it with soap and water or a glass cleaner. It really does make a difference. Plus, you wont kill your Sharpies as quickly from the greasy build up you’re tracing onto.
2. Use good lighting
Such a simple strategy but you might not realize how poor your lighting is until you add more light to the area.
The way I used to have my workbenches set up, the primary source of light was behind me but there were many other lights about the studio. I didn’t realize that I was casting small shadows until I brought a desk lamp over to us on that bench while painting glass.
Sometimes we get so comfortable with our setup, we overlook the simple things.
3. Use a cutter that's comfortable
There are many different styles and manufacturers of glass cutters. If you have carpal tunnel, arthritis, weakness or some other sort of condition that affects your hands, you’ll want to be extra aware of your hand and arms positions while using the cutter.
If there is a glass studio nearby, ask if they have any cutters you can try before you buy one. There is no way to know which type will work best for every person.
I’m a firm believe that if you’re hand and wrist are comfortable, you have a higher chance of making solid and accurate scores.
4. Always cut on the smoothest side of the glass
So you found a beautiful glass that you absolutely love. That’s great! There are so many stunning colours out there, but if you’re new to cutting glass, you’ll also want to take into account how much texture it has.
Heavily textured glass can be more tricky to work with but it doesn’t mean that all of them will be more difficult to cut.
In order to run the cutter smoothly across the glass, you need to make consistent contact with it. If your cutter is bouncing up and down as though you are skiing through moguls, chances are that you probably aren’t able to keep an even pressure as your hand and cutter go up and down over the hills and valleys.
If you happen to have a heavily textured glass, you’ll always want to cut on the smoother. This means that if you want the texture to be facing the good side of your finished stained glass piece, then you simply have to turn the pattern piece and the glass over and trace the flipped pattern piece onto the back side of the glass (the smoother side.)
5. Cut your template pattern accurately
Having all the glass cutting skills in the world won’t help you if you have poorly cut pattern pieces to trace from. If you’re of the method of cutting your pattern out on paper or card stock and using that as a template to trace onto your glass, take your time cutting the paper pattern. You have little chance of cutting the glass to a perfect fit if the pattern piece you’re tracing isn’t the right size to begin with.
6. Take your time to trace the pattern
This might seem super simple, but it might surprise you just how many people rush through this step. If you aren’t careful, the template could slip and you could inadvertently change the shape of your tracing. If you have trouble holding the template while tracing it, you could try using a piece of rolled up tape underneath to help steady the pattern piece.
7. Tracing close to the edge of the glass
If you’re conscious of placing your pattern template very close to the edge of the glass, this tip’s for you.
Removing a narrow sliver of glass is extremely difficult. I know you might be tracing your pattern close to the edge of the sheet of glass to save on waste glass. It’s a very good practice be conscious of not wasting glass but keep in mind that you might be making things harder on yourself than necessary.
If you want to use the very edge of the glass because it’s straight and your pattern piece has a straight edge, go for it! But if you have a sliver that you need to remove, make sure to give yourself no less than 1/4 inch of space to the edge. This will leave enough bulk in the piece you want to remove, that you should be able to break it off clean.
8. Use cutting oil
There are so many schools of thought for using cutting oil, I’ll let you decide for yourself which one works best for you.
Have you ever noticed on the back end of your cutter, there’s a little cover that unscrews to reveal a hollow center the length of your cutter? That is there to hold oil. But before you go and fill it up, let me explain a little more.
When I first heard that you could fill the cutter, I mistakenly thought that meant that I should fill it. I was told that tightening the cap or loosening it slightly would allow for faster or slower flow of the oil as I was scoring glass. I’ve always used good quality cutters but anytime I filled one, I regretted it deeply.
Don’t misunderstand me, there were no issues with the glass cutting itself but once I startrf handling it and using breaking pliers, I had a smeared mess of oil all over the glass, the tools and my hands. And guess what? If you miss cleaning any of it up, your copper foil wont stick! Yes, I learned that one the hard way too.
Now please don’t think that oil is a bad thing. A lubricant is actually quite necessary to keep your tool working efficiently.
- It helps keep the carbide wheel turning freely.
- It helps to remove and prevent build-up of any little glass particles around the wheel.
So here’s what I do. I took a small mason jar and cut a piece of soft rag to stuff in the bottom. Then I poured some oil into the rag. You don’t want to float the rag in the oil. You just need enough to dampen it. Then you can stand your cutter in the jar with the wheel end on the oil soaked rag. Your cutter has a soft, cushy place to stay until the next time you need it and the oil helps keep it conditioned. You’ll find this especially helpful if you work in a shed or garage. I’ve had students mention that their cutters have gotten a tad rusty until they started using this storage technique.
Then, each time I pull it out to use it, I drip a little oil onto the wheel, roll it around on the palm of my hand so that it is ready for use but doesn’t leave smears of oil all over my project.
9. Should you push or pull the cutter?
You’ll find that this is another area where people vary. When I’m teaching, I encourage students to try it both ways and see which is more comfortable. That being said, I do believe that pushing the cutter away from you has many more benefits than pulling it.
When I’m glass cutting, I like to “lock” my elbow against my side before starting the score. I can judge the pressure better when I work close to my body. As I push the cutter away from me, I can extend my arm at the elbow to finish the score. I get a more even pressure this way.
Also, when you’re pushing the cutter, you can see the notch in the tip where the wheel sits. Use this notch as a guide and follow it directly in line with your traced pattern. Your score will be exactly where it’s supposed to be!
Try following the line when you pull the cutter. It’s near impossible as your hand is blocking the view of the trace line. You end up contorting yourself to be able to see what you’re doing. Glass cutting is not part of a circus act, although many people who have never seen it done before become just as enthusiastic a spectator!
10. Angles make a difference
Hold your cutter perpendicular to the glass. When the handle of your cutter leans left or right while you’re cutting, once you break the score, the glass will tend to have that same angle along its edge. This mean that the front and back sides of the glass are different in size and this will affect the way the pieces fit together.
11. Stand while scoring
You need solid, fluid movements that glide your cutter smoothly from one edge of the glass to the other. When standing, you're able to move your whole upper body freely. This allows more movement of your arm and shoulder resulting in more even pressure and an easier time getting around curves. These more fluid scores will definitely improve your glass cutting.
12. The right amount of pressure
Remember, the objective is to score the glass, not mash it. Learning the right amount of pressure to use for glass cutting is tough and it takes time. Listen for clicking and popping sounds or something that sounds similar to a zipper.
A good score should look like there is a piece of hair sitting on the glass. When you have a whitish score line or it appears chipped, you’re pressing too hard. When you lighten your score, it will break more consistently.
But... be sure to use enough pressure. Sometimes when new hobbyists arrive for their first lesson, they are too light and timid with their cutters. This means that they aren’t able to get a complete score from one edge to another. If you cannot see your score at all, you need to practice using a heavier hand with your cutter.
13. Glass generally wants to break in a straight line
Use this knowledge to your benefit. Trying to force a very sharp curve in one score is not going to give you the break you want.
Sometimes, we just need to make a few more breaks with less curve in each. This way, we can create the shape we want without accidentally causing a break to happen in the wrong place.
14. Practice makes a more confident maker
As with anything, it takes time to learn new skills. If you’re new or still struggle with glass cutting, practice short cuts of just a few inches. Ones that are straight or slightly curvy are perfect for getting the feel for what you’re doing.
Once you’ve got the hang of that, then you can add longer scores to your practice.
I spend on average 40 minutes with beginner student letting them practice basic glass cutting skills on window glass. Give yourself the opportunity to make mistakes, this is how you’ll learn.
Window glass is the best thing to practice on as there’s less stress over the cost of materials. You might even be able to get it free from old windows or even window retailers. Many of them have so much scrap window glass, you might even be able to score some for free!
If you’re more experienced at glass cutting, try to push yourself (at times.) You need to push outside your comfort zone so that in time, you’ll be able to do even more. Being “safe” and not pushing yourself can stifle your ability to learn and master this essential skill.