Pattern Pieces

When the pattern is correct you can start making pattern pieces. Use light weight cardboard, something like poster board or even file folders, if you have any spare ones laying around.

The cardboard pieces will need to hold up while going around them with a marking pen, and cutting and grinding around them. Cereal boxes, the backs from paper pads, cardboard inserts, etc don't hold up once they get damp. The shape distorts and you're back to square one with accuracy.

Sandwich carbon paper between the pattern and the cardboard, making sure the carbon side is facing the cardboard. Hold the three pieces together with paper clips. Use a medium ball point pen to trace over the pattern lines.

Number the pattern pieces and the pattern, and draw directional lines if you are using glass with a definite direction. Flower petals look funny with some of the lines going across and others going up and down.

Here is where you can chose how to cut them out. If you use pattern shears and they cut out a line exactly the same width as the medium ball point pen line, go ahead and use them. Make sure the lines are centered on the shears.

If you don't use pattern shears, cut them out with sharp scissors (my preference), cutting on either side of the line. When you are done, you should have pattern pieces with no pencil or carbon paper lines on any of the edges.

Lay the pattern pieces on the pattern/cartoon and make sure they fit perfectly inside the lines. You should be able to see the lines all around each piece. Don't forget the "A" word. Accuracy.....

Lay the pattern piece on the glass
and trace around it with a Sharpie.

The pattern is now
accurately traced on the glass.

Cut the glass precisely on the inside edge of the line.
Then lay the cut glass on the pattern piece, or on
the pattern/cartoon to check it for accuracy.

If there are any places that need grinding, mark them with the sharpie and grind. You will find that there will be many pieces that do not need grinding. Yes, I'm an advocate of only grinding if needed. I do not grind every single piece.

Here's what I do if a piece doesn't need grinding to make it fit properly:

1. Swipe the glass edges with a carborundum stone, but only if the edges are sharp enough to damage the foil or cut fingers.

2. Give the edges a quick wipe with alcohol to get rid of the oil from the cutter. The alcohol evaporates quickly so you don't have to wipe it off.

3. Foil the glass. Yes, I usually foil as I go.

4. Get on to the next piece.

For lead, I do nothing unless a piece needs to be ground to fit properly.

Cover the cardboard with contact paper, both front and back, before cutting out the pattern pieces. If you are cutting multiple pieces of glass using the same pattern piece, contact paper is a good idea. The plain poster board/cardboard only holds up for so long, then it begins to deteriorate.

Spray the cardboard with acrylic waterproofing spray and let it dry before you start cutting out the pieces. I would do this if I were going to use them multiple times, but it seems like a lot of time and money spent for a once only use of each pieces.

Glue the pattern piece to the glass before cutting the glass. Many people like a physical edge to cut and grind along. I've seen them use glue sticks, double sided tape, rubber cement, and spray adhesive. I'm sure there are other ways of sticking it down that I'm not aware of.

Use a paint pen or metallic marker, rather than a Sharpie, to draw around the pattern pieces. It won't come off when grinding or using a ring saw. A white paint pen works well on very dark colored glass.