Pattern Pieces

This tutorial is about pattern pieces,also called templates, how to make them and how to use them on your stained glass. However, before we start with making them, I want to talk about accuracy.

The key to success, when making a stained glass project, is accuracy. Plain and simple, it is either accurate, or it isn't.


"That's good enough" or "that will do" are not phrases we use when making anything out of stained glass, whether it's a window panel, lamp shade, suncatcher, box, or anything else you can think of.

It all starts with your pattern. If it isn't accurate, you'll have problems in every step from there on. You'll have to adjust pattern pieces, re-cut glass, fill in big gaps with solder, use wider or narrower lead or zinc around the outside to make it the right size, or worse yet, have to start over because it is too far off to fix.



One word here about photocopied patterns. Photocopiers distort patterns. It may not be enough to notice, and if your project is free form, it probably won't matter.


However, if your pattern is geometric or has to fit a specific measurement, check it before you start making pattern pieces to make sure it is accurate.

If it isn't accurate, now is the time to fix it. Make sure parallel lines are parallel corners are square, dimensions are exact, anything it takes to make the pattern accurate.


As a side note: even patterns from books can be off, so check them before you begin a project.






Making 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 each template piece as well as 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 template 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.....








Tracing Around The Pattern Pieces


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 template, 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.