Below is a photo of some examples of pieces which are better cut by machine than by hand. Each of these has deep curves and one has a very thin piece. Chances of breakage if cut by hand are high for these kinds of cuts.
Here's a better look at my Gryphon Omni II Diamond Wire Saw which cuts in any direction. If you look carefully at the piece just cut, you'll see that a cut like that cannot be made by hand. The machine produces very precise cuts and is invaluable on a project such as this.
Here's an example of a very thin, single piece of glass which I actually did cut by hand. This is one of the stems in the design. Its a rare example of a successful, very narrow, hand-cut piece. The glass is a 40-year-old dark cathedral brown that is thinner than most other glass. It is very "agreeable" in that it cuts very precisely and rarely breaks badly. Most other glass would not be so forgiving on such a narrow piece.
Notice below that I've traced the three pieces of glass with a silver Sharpie pen instead of black. Its a little harder to wash off but the only way to mark dark glass. These pieces need to be scored inside the silver line, however. The blue tool shown is a pair of "running pliers". I've scored a lightly curved line around the outer edge of the pieces. I line up the "bump" on the top of the running pliers and apply light pressure. The glass snaps instantly. Then I go back and use the electric saw to separated two of the three pieces of glass. I separated the piece on the right by hand cutting. Each piece of glass has to be evaluated on what type of cutting will be most effective and give the least chance of breakage.
Here's a handful of cut, grinded, washed and dried pieces of glass ready to be placed into the pattern.
With every stained glass project, some glass always needs to be trimmed. The need for trimming is even greater when there are more individual pieces, such as in this design. Even though the pattern is drawn with hairlines and the glass is cut very accurately, the glass is often too large for its "assigned" space. This is normal. Below, I've overlapped two pieces of glass and I'm drawing a black line on the bottom piece which is a bit too large. Then I'll go back and re-cut the excess glass on the bottom piece to make a perfect fit. This trimming process often has to be done repeatedly to assure that the glass fits well.
Here are the bottom two panes with all of the glass cut. More trimming may take place when I get to the copper foil process which I'll start after all six panes are ready The symmetry of the design is more evident now. I'm using the mullions (the dark brown strips) to contain the glass within the perimeter, the same as the metal fence is doing. The mullions will be more accurately cut as the project moves along.
I'll be cutting glass for the next week or two .. I'll be back when the next two panes in the middle section are all cut. Those panes are similar to the two just cut, but are their mirror images. Stay tuned ...
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