#1 = 0 (start of arc)
(Start at 0,0,0)
(Move to x1) G90 G0 X1
(Activate XZ plane) G18
o101 while [#1 LT 360]
g10l2p1x1r[#1]
g90 g0 x1 y0
(Cut arc inwards and down) g91 G3 X-.25 Z-.25 R.25f10
(Rewind one step) G2 X.25 Z.25 R.25
#1=[#1+1]
o101 end while
m30