The jig I'm using here is a Dupli-Cutter from Micro Mark. In addition to
that, you will need an Xacto knife, a small metal ruler, and a small file.
The jig allows you to hold the piezo and score along a straight line, but
you could make do without one. The photos will give you an idea of how to
make it work. After the piece is cut, you can clean up the edge of the piezo
by using the file. Bordered photos link to larger images.
The first step is to mark the piezo for cutting. I wanted to split this
piece into thirds along the length. This will give me pieces narrow enough
to make an under-the-saddle guitar pickup.
Then I position the piezo in the jig. The aluminum plate is used to position
the piezo so that the first pencil line is flush with the top bar. When the
piezo is in place, I pull the place back and snug up the red thumb screws.
I use an Xacto knife to score the ceramic along the edge of the bar.
Although the photo doesn't show it, I hold the top of the bar against the
piezo with my left hand while I score with my right. I press the bar down
directly over the piezo to keep it secure. Use just enough pressure on the
knife to scratch into the material a little bit at a time. Be careful to
score evenly from edge to edge. After a few minutes of work, the piezo will
separate along the cut line.
The cut edge of the ceramic will not be perfectly straight. They are often
smooth enough for most purposes, but if you want a finer edge, you can
smooth things up with a file.
Place the piezo on the back side of the jig. Position it so that the rough
edge of the piezo extends slightly beyond of the edge of the jig base.
Next, place your metal ruler over the piezo to hold it in place while you
file the edge. You could not do this with the other side of the jig because
the bar and the edge of the jig are not flush.
You will want to smooth the edge of the cut piece as well as the edge of the
It is not too hard to cut pieces as narrow as 1/16". Cutting the wafer into
thirds gives you pieces that are between 1/16" and 3/32" when filed smooth.
Occasionally one will break, but even the small pieces can still be used. I
use copper foil tape with conductive adhesive to make connections. This will
form a connection even across broken pieces of piezo.