FAQ Index

Light Table

Construction / Molds

Choosing Glass

Pattern Preparation

Pattern Hints

Scoring / Breaking Glass

Grinding

Foiling

Fitting The Glass

Lamp Positioners

Solder / Soldering

Reinforcing Lamps

Special Considerations

Filigree

Releasing a Shade

Ring and Rim

Patina

Polishing

Special Applications

Tools, Aids etc.

Health & Safety Concerns

Designing

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Workshop Renovations

Photographing Lamps

SCORING/BREAKING GLASS

IDEAS ON SUCCESSFUL CUTTING

Barbara Grollo: With my pattern pieces laid out on the full sheet of glass, I tend to score the inside curves of each pattern first and, until I have that out of the way, I don’t score around the rest of the pattern. (I want the glass as stable as possible for the tugging and pulling that happens as I groze the scores from the glass.) I try to leave as much glass as possible behind the curve for even more stability. Once that’s done, and depending on how many pattern pieces are laid out on the sheet, I try to isolate and separate the pieces. At that point I make the rest of the scores that are needed for each piece. I groze and break away the glass in the same order in which they were scored.
Peter Grotepass: The more scores you make around your pattern piece, the easier it is to groze and reach your final inside score without breaking the piece.
Lorrie Gordon: I took a class from Don Able of Morton Tools. Don said that most 21 people use too much pressure when trying to cut art glass because of the challenge to keep the cutter from bouncing around the surface divets. Pushing too hard might result in small fissures on the cut line that will cause the glass to run breaks perpendicular to the cut line.”
Carol Conti: Your cutter must be sharp and lubricated in order to make a good score. (To check out your cutter to make sure it isn’t skipping, make a score on a piece of mirror.) Too little pressure can result in the glass not breaking for you; too much pressure can cause breakage where you don’t want it. Each sheet of glass seems to be unique, so experiment on an edge before you cut into a whole sheet. If you are having trouble cutting and breaking glass, try using running pliers. Heating the glass on the light table also helps the glass make its proper break on your score line.
Lynn Perry: I like to do my cutting on a light box. Unfortunately, the light box glass is not a very yielding surface and causes extra breakage and some poor cuts. To solve this, I put a thin piece of packing foam on top of the clear glass, but then this made it difficult to rotate the glass while cutting curves. The final solution was to put a smaller piece of clear glass on top of the 1/4” light box glass and put the foam on top of this glass. Now I can still see the cutting lines and can easily rotate the glass as I am cutting. When I cut textured glass, I use a thicker piece of foam.
Dick Watson: When you have to cut a small or awkward piece of glass, leave a portion of glass about 2” on the easier side. Cut and grind the more difficult sides first and then break off that extra portion and grind it to fit.

GROZING
SB Anthony: For grozing up to the score line if the break was outside it, I was given this advice: don't twist down as is the natural tendency, pull straight away from the edge.

MORTON SYSTEM
Emily Klaszac: I have used the Morton system for about 10 years, but only for cutting 90 degree angles. It is wonderful if you have to cut a lot of pieces of the same width for a border, to make boxes, etc. but I will not use it to cut gridwork or panel lamps because it is difficult to get an accurate angle consistently through the cutting of your project. So when doing a lamp with gridwork I use the Morton to cut strips of glass to the depth (vertical measurement) and then use a template to draw angled lines for the pieces.

MOSAIC CUTTERS
SB Anthony: I’ve discovered that mosaic cutters make excellent grozers when trying to cut a long skinny piece. I cut wide, then nip away the glass until I am quite close to the line. Sure beats grinding!

PROTECT WHEELS WITH OIL
Marie Jo Murray: While attending a Glass Trade Show, I learned that, to save wear and tear on those expensive mosaic cutter carbide wheels, you should dip them in oil - just as you would glass cutters. Also want to let you know that unscented Kerosene works as well as oil!

OIL CUTTER PROBLEMS
Mike Barnes: I use a glass cutter with a built-in oil reservoir, but sometimes the oil doesn’t flow. I’ve found that by unscrewing the top a few turns, air is let into the reservoir allowing oil to flow again. If I still have a problem, I make sure that the wick is in contact with the cutter wheel. (Hold the cutter up to the light in order to get a better view.) If there seems to be a gap between the wick and wheel, I remove the cutter head and very gently pull the wick out until it is in contact with the wheel. At this point, it also 22 helps to dip the wick in some oil.

TIPS ON CUTTING GLASS
Notes taken by Nikki O’Neill during a workshop by Nancy Underwood at Weisser Studios.
•Scoring Tools
A Carbide with a narrow wheel angle is our most important tool.
Nancy prefers the cutting wheel of Toyo and pointed out that Toyo heads can be used on other cutters.
•Cutting Oil
Oil facilitates the breaking of the score -it's more important to use on difficult glass, thick, pre-fused, etc. or on difficult cuts. If your cutter leaks, like most Toyos do, you can just dunk the tip of your
cutter in oil. Nancy keeps a small dish with a paper towel soaked in cutting oil handy. She also uses the Toyo with a swivel head.
•Techniques
Over-scoring will make the glass difficult to break. If you are using a Toyo pistol grip, you should exert just enough pressure to close the spring in the cutting head.
Cut a straight line by using a cork-backed ruler. You can create your own by buying any size metal ruler and gluing cork onto the back.
Also useful is an L-square with a ridge which can be aligned against the bottom edge of the glass.
If you do lots of straight-line cutting you can install a jig. (Such jigs are available at retail glass stores.)
•Running/Breaking Tools
Running pliers: those with metal handles are better because you can feel when the break has started.
Breaking or grozing pliers:
Hold these pliers so that the curved jaw is on the bottom (smiling!); however, to break out a long skinny strip, position the curved jaw on top. When using breaking/grozing pliers remember to apply pressure out and down to help the score run from the top of the glass through to the bottom. Don't torque the glass with upward pressure.
Two Morton system "button" based systems were demonstrated for pressing along the score, the bridge and button and the M-80. The Ringstar works along the same principle and both work best using light pressure.
•Principles of Breaking Glass
Glass prefers to break in a straight line and along the path of least resistance. Don't put your pattern piece too close to the edge of the glass in case the glass break runs off the score to the edge. Leave at least 1/4 to 1/2 inch between the pattern and the edge of the glass.
To cut a skinny strip, i.e. one fourth of an inch wide:
1. Score your line using a cork-backed ruler.
2. Use narrow-tipped grozing pliers.
3. Start at one end of the score and gently work from that end toward the other...running the score until the strip comes free. Remember to position the curved jaw of the pliers on top.
•Glass Cutting Rules
The piece you are saving should be bigger than the piece you are cutting away. Don't try to cut a small pattern piece off a big piece of glass; rather, cut off a piece of glass with enough room for your pattern piece plus 1/4 to 1/2 inch extra.
Cut tight inside curves first by making multiple parallel scores. Cut them all at once before using narrow grozing pliers. This way, if one score runs straight off the curve, the next score will catch it.
Starting with the outermost score use grozing pliers to work from side to side toward the middle until the piece comes out.
Repeat with each score - working your way in to the curve. (A tighter curve may need more cuts.)
If you have compound curves, you may need to cut more than one series of multiple scores.
Peter Grotepass: If you are cutting glass and find that a particular glass seems to break wherever it wants to, try applying a little cutting oil to the glass before you make your score.
Chaz Smith: When cutting a pattern piece that has an inside curve, score a series of crescent moons so that no score ends up pointing at the pattern piece. Try using mosaic cutters. By function, they remove little moon shaped bits, so it’s not too hard to get those inside curves.
To check on your cutting skills, take a piece of glass (window glass if you have it) and make a straight six inch cut using little pressure. After breaking it, look at the edge to see the actual score line. If done correctly, it will be a tiny rough edge with a nice smooth break beneath. Now, make another cut, but press down hard this time. When you check the edge of this one, you will see a more angular break, with some deeper fractures caused by the score. It’s those deep fractures that lead the glass to break off-course. Lighter pressure is definitely needed when working on glass that is uneven in texture and hardness.

CUTTING SPECIAL GLASS
Mike Barnes: Since all glass is different, I do some practice cuts on the glass that I’ve decided to use for a new lamp. I’ve found that Youghiogheny takes a softer touch - even laying it down on top of a towel sometimes helps.
Lorrie Gordon: I warm my glass (before starting to cut) by letting the glass sheet rest on an old heating pad until it’s warm to the touch.
Ed Minas: When cutting ripple and heavily textured glass, I place a piece of inch thick rigid styrofoam under it. This trick really prevents unplanned breakage.
Carol Conti: Experiment by tapping the underside of your score on drapery or other heavily textured glass to facilitate a clean break.
Barbara Grollo: After having numerous pieces of ripple glass break in the valley instead of at the hill, I pulled out my mosaic cutters and used them to snap the glass at the correct spot. I also found that it worked well for grozing away small areas. I found that my regular groziers kept slipping off the ripple glass, but the blades of the mosaic cutter were able to grip the glass. This tool might not work as well for the usual glass pieces, but for borders it was a real “glass saver”.
Chaz Smith: Cut on the smooth side of drapery or ripple glass, but beware of the knife-like edges that can be left on the peaks of this glass as you break it. (You can use a grinder to smooth away dangerous areas.) As to the issue of foil, I use 2 mil since the extra thickness gives more material to stretch as you burnish. I use 7/32nd foil and apply it with the right amount of overlap on the back. Burnish the edge and back, 24 then go to the valleys on the front. I don’t worry about peaks that extend beyond the foil - just leave them exposed. Work the foil over and down the sides of the peaks. If the ripples are small, you’ll be able to burnish right to the bottom of the valley without tearing the foil. If they are high peaks, it’s impossible to keep foil in contact with the bottom of the glass, so I burnish down as far as I can without tearing the foil. then lightly burnish the foil in the middle so that it folds over with the edge pointing down towards the glass. This way, there are no tears, no apparent loose foil edges and the valleys are sealed. In places where the glass has few ripples, 7/32nd foil is really too wide, so I trim the foil with an exacto knife. Small foil tears can often be covered later as you do your beading with solder.
Larry Cartales: I worry about exposed ripples so I use several widths of foil - even up to 1/4” wide. I sit as patiently as I can with my sharp exacto knife and trim the foil so that I end up with an even overlap all around the piece.
Pierre Leblond: If I want the deep (3 or 4 mm) ripples on borders or trellisses to face outwards, I add foil to cover the exposed peaks. I straighten the foil in the valleys with a scalpel - which is tedious work! If I have the ripples facing inwards, I bevel the peaks slightly with a grinder (except for the edge against the rim). This accomplishes two things: it makes foiling and fitting easier and it ensures no cut fingers from any exposed peak when I handle the shade.