Page 276 - CNC Robotics

CNC Robotics

As you ca n see from the small and large plots of the bulldog. vec-
tor images ca n be enla rged or red uced without loss of detail. I used
the same pen for both plots. wh ich resulted in the smaller bu lldog
plot 's having pen lines that bleed into each ot her. This gives the
final plot a little less resolution . Had I used a pen with a smaller
tip, ga uging the tip to the size of the plot, the two images would
look exactly alike.
My next plotting task was to find a pen that could be used to plot
on glass surfaces, with ink that would act as a resist to glass etch-
ing paste. It took a wh ile to find such a pen . I bo ught every per-
man en t marker availab le and tes ted them by drawin g a line on a
piece of glass with each and ap plying etc hing paste to each line,
letting the paste sit for about 15 minutes and washing it off in
soapy water. The on ly pen that wo rked well as an etching res ist
was the Pilot Extra Fine Meta llic Ink Marker. I plotted a dolphin on
a piece of clear glass using the Pilot Metallic Marker. Then I added
ink to the perimeter of the drawing with a wider version of the
same pen so that the etching paste wouldn't stray from the area I
wanted to etch. as you ca n see in Figure 12.4.

Figure 12.4

Dolphin plotted with
metallic ink.

Make sure that the ink ha s been ab le to dry completely before
usi ng the etching paste, or the paste an d ink will just mix and your
glass etch ing will not be successful. Be carefu l to read the safety
warnings on the etching paste, as it is a caustic substance. I

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