spirals in grbl:

G01 G91 Z-0.6533 F100.
G01 G42 D08 X0.0235 Y-0.0939 F10.
G03 X0.0939 Y0.0939 Z0.0179 R0.0939
G03 X-0.1179 Y0.1179 Z0.0179 R0.1179
G03 X-0.1185 Y-0.1185 Z0.0179 R0.1185
G03 X0.1191 Y-0.1191 Z0.0179 R0.1191 F16.
G03 X0.1196 Y0.1196 Z0.0179 R0.1196
G03 X-0.1202 Y0.1202 Z0.0179 R0.1202 F26.
G03 X-0.1207 Y-0.1207 Z0.0179 R0.1207
G03 X0.1213 Y-0.1213 Z0.0179 R0.1213
G03 X0.1218 Y0.1218 Z0.0179 R0.1218
G03 X-0.0975 Y0.0975 Z0.0179 R0.0975

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