#<dia> = 1.0 ;#1 (=1.0 Diameter)
#<rad> = 0.375 ;#2 (=.375 Radius)
#<z_start> = 0.000 ;#3 (=0.000 Z Start)
#<doc> = 0.025 ;#4 (=.025 DOC)
#<feed> = 5 ;#5 (=5 Feed)
#<tool> = 1 ;#6 (=1 Tool)
#<sfm> = 100 ;#7 (=100 SFM)
#<rpm> = 2000 ;#8 (=2000 RPM)
#<coolant> = 9 ;#9 (=8 Coolant)

#<step> = 0

G7 G18 G40 F#<feed>
G96 D#<rpm> S#<sfm>
T#<tool> M6 G43
M3 M#<coolant>
G41
G0 X[#<dia> + 0.1] Z-#<doc>

o100 while [#<rad> GT #<step>]
#<step> = [#<step> + #<doc>]
G0 Z-#<step>
G1 X#<dia>
G2 X[#<dia> - [#<step>*2]] Z0.000 I-#<step> K0.0
G0 Z0.1
X[#<dia> + 0.1]
(debug, #<step>)
o100 endwhile

G40
G53 G0 X0 Z0
M2