Below, I'm placing a pattern piece into the open space, just to be sure it will be a good fit. Glass is not flexible. Within reason, each piece has to fit perfectly. Notice that I've lightly marked an arrow in the center of the pattern piece. This shows the direction of the waterglass. Waterglass has a definite texture and in this window, each piece has been cut and soldered in a vertical format. Therefore, all the replacement pieces must also be cut vertically.
Next, the copper foil is pressed onto the glass using a flexible plastic wand or "fid". Its important not to allow any chemicals or solder to get under the foil.
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