To hold the centerline on the workpiece will help the device shown in the figure.
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GLASS TIGHTLY
The hour glass slipping from its frame, it is necessary in the edge of the recess on it gently to apply a little glue of type "Moment" and, setting the glass in place, gently loading it...
GLASS CUTTER WITH COMPASS
To cut a round hole of large diameter, to make a glass disk or a ring will help this simple tool. It consists of three parts. The dimensions of the steel rod Ø 5 mm depend on the...