Trimming up pieces of glass to reduce grinding

Hi Sue,

I just discovered your awesome website tonight. WOW... You sure have a lot of very helpful information here!! Thank you for that!!

My question is this... How do I properly use grozing pliers to "nip" or "trim" up glass pieces to reduce the amount of grinding that is needed? I took a class several years ago, and the teacher made it look very easy - he just grasped the glass with one hand and grozing pliers with the other. Then voila... he instantly snipped away small pieces of glass with the grozing pliers. I always seem to "crumble" my pieces, though, rather than nip or trim them. What am I doing wrong? Do I use downward motions rather than "pulling" straight apart?

Thank you for any help you can offer! This is one part of stained glass that I really dread! Making neat solder beads is the other... I'm going to try the suggestions I read on your website for that next time, though, so maybe I'll have better success with that part of it!


Hi Kelly,

What a great question. Grozing is not a common way of trimming glass any more, since the invention of the grinder. I must admit that I seldom groze. I learned, early on, to cut accurately since there were no grinders back in those days. I had a carborundum stone to take off sharp bits, and I still use one to run around the edges of my glass after I break it out.

How to Use Grozing Pliers
Most people use the combination grozing and breaking pliers. If you have a good look at them, you'll see that one jaw has a flat surface and the other jaw is rounded. The flat jaw should be up if you are using them as breaking pliers. The rounded jaw should be up when you use them to groze. Use one hand to hang onto the glass. With the other hand, roll the serrated surface of the pliers over the edge of the glass, removing any unwanted bits.

The easiest way to hold the pliers is to place your index finger between the handles and use the rest of you hand and your thumb to open and close the pliers. This will give you excellent control, and it prevent excessive pressure (which you don't need when grozing).

Kelly, you asked about pulling downwards or out. If you're taking out larger chunks of glass, grab the glass with the corner of the pliers and give a quick twist with your wrist. Once you have the pieces removed, go back and roll the curved jaw over the edge of the glass to smooth it out.

One final comment. That is to suggest that you learn to cut more accurately. Accurate cutting eliminates a lot of grozing time and grinder usage. If you read my page on "cutting glass", you'll learn a lot of techniques that will improve your cutting skills.

Practice cutting on scrap glass, then practice some more. Each time you cut glass you'll learn something from the experience. Over time you'll find less and less need for grozing or grinding.


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Using a Grinder and Foil Losing It's Stickiness
by: Sue

Hi Kelly,

Here are the answers to your most recent questions.

Yes, use your grinder when you need it. It's a wonderful tool; however, you do not have to grind every piece before you foil it. Just swiping the edges with a carborundum stone or the edge of another piece of glass is enough to dull the edges to prevent cuts to you and the foil.

Carborundum stones are available a hardware stores. Even WalMart has them in the hunting department.

If the glass is clean, the foil will stick just fine. I wipe the edges of my glass with alcohol just prior to foiling.

I am working on a copper foil tutorial and it should be on this web site in a week or so. I know you'll find a lot of answers there.

As for foil not sticking...yes, it happens. I really don't know if age has anything to do with it, but moisture, and direct sunlight are contributing factors. I have 6 year old foil that sticks perfectly well. Keeping your foil in a sealed bag, out of direct sunlight will help to keep it fresh.

I can't say for sure why your foil lifted in spots. Be sure that your glass is absolutely clean before you start foiling. Burnish the foil well. Make sure it's tight against the glass. If it isn't tight, flux can get under it and cause it to lift.


Thanks Sue!
by: Kelly

Hi Sue,

Thanks for the quick response!

You're right... I really should learn to cut more accurately right up front. I do rely on my grinder too much. But, isn't a grinder necessary to remove sharp edges and to prepare the pieces for the copper foil? That's what my teacher told us... the copper foil wouldn't stick to freshly cut pieces of glass because it's too slick or something. ???

Speaking of copper foil not sticking... Does it lose it's stickiness after awhile? I had a roll sitting around for a year or two and used it recently. As I was soldering, it lifted off the glass in several places right before my eyes!! I had a roll of more decorative foil (wavy edge) that was older and it stuck just fine. ???

Thanks for your help,


Kelly, when I started working with glass there weren't any grinders for home use. Just professional studios had them and if you think they're expensive now you should have seen the prices then! A studio owner had to be fairly wealthy to be able to afford one.

I have foiled many pieces and never ground the edges in preparation for foiling. I wipe the edges with alcohol and put on the foil. It sticks just fine. If I need to remove a sharp bit I give the edge a quick swipe with a carborundum stone before I wipe it with alcohol.

Yes, once in a while you'll find a roll of foil that has lost it's adhesive power. Leaving foil in extreme heat can contribute to it, and working one area for too long can cause it also.

Quite a few people keep their foil in the refrigerator to prevent it from being exposed to extreme heat (obviously it doesn't help with the working one area too long issue!).

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