[pippin88]

I'm having a problem with Solidcam 2014 gcode generation for my lathe.

I use a friend's seat and have cobbled together my own post processor for a LinuxCNC lathe (I don't have access to a reseller post because I'm just using his seat).

I'm making a poly-v belt pulley.

Solidworks 2014
Solidcam 2014

When I try to run the code to profile the pulley grooves, I get an error in LinuxCNC: "Current point same as end point of arc"
It points to this code:

G1 X75.
G3 X74.2062 Z-3.4819 R0.6032
G1 X71.964 Z-3.89
   X73.84 Z-4.231
G3 X73.84 Z-5.8887 R0.88185 (this line errors)
G1 X71.964 Z-6.23
   X73.84 Z-6.571
G3 X73.84 Z-8.2287 R0.88185 (this line errors)
G1 X71.964 Z-8.57
   X73.84 Z-8.911
G3 X73.84 Z-10.5687 R0.88185 (this line errors)
G1 X71.964 Z-10.91
   X74.206 Z-11.318
G3 X75. Z-11.8849 R0.6032
G1 X75.486
G0 X87.
   Z3.
M30
%

GWizard editor gives the following:

Line 593: G3 X73.84 Z-5.8887 R0.88185 
G3: Counter-clockwise circular interpolation (move in a circular arc at feed speed)
Relative IJK resolves to absolute IJK = I73.84 J0 K-4.231
 (R)adius = 0.88185
Helical interpolation along Z-axis. Helix depth = -1.6
 Arc endpoint: 73.8400, 0.0000, -5.8887
 Arc center coordinates: 73.8400, 1.7637, -4.2310, radius = 2.4205 (determined by R)
 Arc angles: 270.0 to 270.0(.0 degrees total)
 Helix pitch in program units = .0
Time: 40:50.5
Adj Time: 40:52.9
V End: 50
ERROR: Current location is the same as the end location for this arc.  

I've worked out I can avoid the error if I don't do a finish operation - I rough and then do a semi-finish (iso turning), leaving only 0.01mm, and the code runs fine.
I've tried finish with stair turning and iso turning - both produce this error.

Attached are:
Image of faulty toolpath (in GWizardE)
Image of working file with 0.01 offset semi-finish toolpath (in GWizardE)
Image of toolpath in Solidcam
.gpp file
.prp file
Full gcode problem file
Full gcode working file with 0.01 offset semi-finish

Help is much appreciated
I spent all day today trying to find a solution to this! I've googled and looked at other posts, and the post (.gpp) manual, but I can't claim to understand a lot of it.