Antique Style Lamp Patterns, Lamp Forms, Stained glass cutting and Lamp construction information
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Glass Cutter

Glass Cutter
    Many types of steel and carbide glass cutters are on the market. There are cutters that oil the wheel as you score, others have special handles for those who have trouble getting enough scoring pressure. There is even a machine that looks like a small sewing machine that applies the correct scoring pressure for you.
    Two popular inexpensive cutters are 7/32” wheel diameter Fletcher No. 07 for harder glass and the small 5/32” diameter Fletcher No. 09 that has been tapered for pattern cutting. Both have a ball end for running the score. The notches are not used. A traditional glass cutter with a ball end is the basic tool needed to work successfully with stained glass. Start with a green 07 and a blue 09 gold ball Fletcher, then after you have mastered the craft, you can invest in a cutter with changeable carbide wheels, such as a Macinnes or Fletcher PSO that will last a lifetime.
    Caution: Never try to draw the cutter over a score line twice; a new cutter can be ruined the first time.



Holding a Glass Cutter
    The traditional way to hold the glass cutter is between the first and second finger. The thumb supports the cutter on the underside allowing a free wrist motion as the cut is made. The cutter should be straight up and down or tipped slightly forward, the pressure coming from the shoulder, not from the wrist or fingers, as you draw the cutter toward you. This is the best way to cut long strips. Fig. C
    To cut a small piece hold the cutter as for long cuts, apply pressure from the shoulder, but push the cutter. This allows you to see the wheel as you follow the mark on the glass. With the other hand hold the glass with your finger tips and use the thumb to help steady and guide the cutter as you push it to make the score.
    Figs A & B are used successfully by individuals who have trouble getting enough pressure with one hand. Look at the center of the cutter wheel; score away from you as you follow the inside edge of the mark on the glass.
     In all three examples the cutter is pushed and the score line is made on the inside of the mark on the glass. Use the way that is most comfortable for you.


Scoring on Glass
    When scoring stained glass, the pressure should come from the shoulder and not the wrist or fingers; do not press too hard. The glass cutter must crush a very small groove in the glass surface. To  check glass scoring pressure hold the cutter against a bathroom scales; 10-12 pounds pressure is the amount you will need.


Fig A.                                                                              Fig. B
    
    The proper amount of pressure will make a small groove with one fracture extending down and the break will follow the score. If too much pressure is applied, many small fractures will run in all directions other than the one extending down from the score line. If tiny slivers of glass fly from the score line, you are pressing too hard.
                                                                                                                    Too Much Pressure

      Correct Pressure   
                                      

    NEVER SCORE OVER THE SAME SCORE LINE TWICE. You may permanently damage a good steel or carbide cutter.
    Try to leave about 1/4” between parts. This allows enough room to grip the glass with breaking pliers for a nice clean break.

Cutting Sheets of Glass
    You will be constantly cutting larger sheets of glass down to smaller workable pieces. Study figs. 1 and 2 . THESE ARE BASIC STEPS YOU MUST LEARN TO WORK WITH STAINED GLASS. To cut glass pieces, you will need to cut your larger stock sheets down to a handy working size, approximately 6” squares. Score your stock  sheet from one side to the other. Always apply pressure away from the score line. To break a strip from your stock sheet, hold the glass securely with your thumb over the score line where the score line runs off the edge; tap lightly with the ball of the cutter underneath the score line. You will notice the fracture widen. The piece should break along the score line. Tapping under the edge to run the score may cause the piece to break completely apart. As experience is gained, you will find that most of the time the glass will break without running the score through at the edge. Do not tap small pieces. Use breaking pliers to break small pieces.
    The glass pieces should be grasped with the tips of your fingers inside, away from the edges. Never grip with the palm of your hand.  Always apply pressure away from the score line. Press the knuckles firmly together, roll both fists out and down applying pressure on the bottom two knuckles, bending and pulling apart at the same time.

    Never force a break. If a score does not break easily, move and redo. Forcing the glass to break can only add to the danger of seriously cutting yourself. Do not attempt to tap small glass pieces, they may shatter.

Cutting Glass to Paper Pattern
    The smooth fire polished side of the stained glass is usually used facing out, this helps in keeping the lamp clean and is the easiest side to score.
    Arrange the pattern in position on the glass strips to cover the portion you have selected. Hold the pattern in place with a small amount of sticky tape. Mark around it with a pen that marks on glass.

    Ink pens must dry fast - such as a Sanford Sharpee felt tip marking pen for use on plastic, glass, leather, etc. A regular felt tip pen for paper does not dry fast enough. Use black or dark ink to mark on light colored glass. Use gold, silver or light colored ink to mark on dark colored glass.

    To score push the cutting wheel so it will score along the inside edge of the mark; pattern marks should be on the scrap. Do not lay the pattern on the glass and score around, the parts will be too large.

    As you follow the pattern make one score at a time. Push the cutter away from you, allowing the cutter to run off the edge, then break apart with narrow breaking pliers. Make the next cut allowing the cutter to run off the edge and break it.

Glass Breaking and Grossing Pliers

    To go with a glass cutter you will need a good pair of combination glass grossing and breaking pliers. Breaking pliers are used to grip and break the extra glass after the score is made. They become an extension of the fingers to grip without crushing the glass. Breaking pliers are the next most valuable tool after the glass cutter for use in small piece, foil wrap work.
    Every score made around each small glass part must be griped and broken away. Grossing pliers enable you to chip away and trim the glass with a rolling wrist movement, to finish small inside cuts, true up trim and bevel the edge. They are excellent for gripping to break out small inside cuts.
    The highest quality grossing pliers and the best I have found are made by Knipex in Germany. They come in several widths, the narrow 3/16” width is perfect for making lamps. They are constructed of soft iron, with teeth arranged on the gripping surface.


3/16" Narrow Breaking and Grossing Pliers

    Experienced glass craftsmen use a combination of accurate glass scoring and breaking, then use grossing pliers for the final trimming. The less you must use a grinder the easier glass cutting becomes.
    For economy attempt the most difficult cuts first, also cut the larger pieces first using the scrap for smaller pieces.


Pattern mark should be on scrap

    Example #1 – The inside cut is the most difficult. Each cut is numbered in sequence. A straight cut #1 is made across the inside cut. This is broken away leaving glass on both sides of the inside cut. Inside cut #2 is then scored and broken out using the corner of your breaking pliers. Work any protruding glass down with grossing pliers, a hand stone or a grinding machine.




    Example #2 – Again each cut is numbered in sequence. Scores 3, 4, and 5, show breaking plier grip areas marked with an X. Grip the glass away from the narrow pointed ends so the break will be toward the narrowest part.

    Example #3 – The inside cut on this piece is too deep to break out in one piece. Two score lines are made, then use the corner of the pliers to break out in sequence 2 and 3.

    Example #4 – Leave extra glass on each side. Make a series of score lines #1-#10. Carefully nibble and break away glass with the corner of the pliers. Your fingers holding the glass must grip firmly and close to the nose of the pliers.


    Compare each glass piece with the paper pattern. The glass piece should be of equal size or slightly smaller than the paper pattern. Use grossing pliers as much as you can, then grind where needed. Rinse each piece and towel dry.


Compare each glass piece with the paper pattern. The glass piece should be of equal size or slightly small than the paper pattern.

Cutting Grid work Freehand without a Jig

    Many lamp designs have grid work. These pieces may be cut out separately or together. Pattern groups allow the grain flow of the glass to extend from one piece to another. For fast, easy cutting, background may be assembled in strips either horizontally or vertically. Assemble grid vertically so that color flow and grain extends from one part to the next. Try to keep the same amount of glass on each side of the score line.
    Supplies needed: scissors, glass marking pen or pencil, sticky tape, cellophane tape, glass cutter, ruler. This method of cutting out grid work differs from using a jig. All the scoring is done freehand – a line is drawn on the glass, glass is scored on the inside or center of the line without using a straight edge.
    Always push the cutter as you score so you can see where you are scoring.
    Vertical: Arrange the background pieces together similar illustration with no space between. Fasten together with cellophane tape. Notch out between the pieces so a line can be drawn on the glass with a straight edge. Score in the center of this line between the parts.
Fig. 3
Tape pattern together. Pattern pieces arranged to cut gridwork vertically.

    Score, break and check fit of one section before proceeding with the balance of the parts. Fig. 3 illustrates how patterns can be grouped together and then cut apart.
    Horizontal: First cut a strip of glass that is equal to the height of each piece. The height of the pieces in each row around the lamp will be the same; however, not all the rows in a lamp will be the same height. Mark each grid pattern on the glass while turning the pattern end over end until you have enough to cover one sectional form or one pattern repeat. Make adjustments if necessary and cut out the number you will need for the entire lamp. Overlap the grid pattern pieces so that adjoining pieces share a score line.


Arrange grid work pattern on strips, mark and score.

Cutting Strips
    To make strips for grid work and borders. Measure and lay out the strips in pairs of 2, 4, 8, 16, etc. This keeps the same amount of glass (mass) on each side of the score line. Score using a ruler or jig starting in the center each time. Run the score to break them apart. Use running pliers on strips that are too narrow to run the score line with your hands.