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
Selling Your Artwork
Workshop Renovations
Photographing Lamps
|
SCORING/BREAKING GLASS
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.
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.
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.
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!
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!
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.
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.
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.
|