Newbie looking for a little help

Hello All, I'm sure that's not a new title.... Hope I'm posting in the right place.

First my problem: diy cnc cutting weird shaped circles. other cuts seem fine.

second Equipment. TB6560 blue board 3 axis from long's motors. nema 23...

Third software: Cambam plus 0.9 trial period and mach3 2.63 (came with the motor kit)

Gcode produced from cambam and it is the same results with other free gcode examples found online...

( Made using CamBam - CamBam CNC Software )
( Untitled 5/30/2013 2:31:14 PM )
( T0 : 0.0 )
G20 G90 G64 G40
G0 Z0.125
( T0 : 0.0 )
T0 M6
( Profile1 )
G17
M3 S1000
G0 X2.4969 Y0.0002
G0 Z0.0775
G1 F10.0 Z0.0
G3 F30.0 X2.5 Y0.125 I-2.4969 J0.1248
G3 X-1.25 Y2.2901 I-2.5 J0.0
G3 Y-2.0401 I1.25 J-2.1651
G3 X2.4969 Y0.0002 I1.25 J2.1651
G0 Z0.125
M5
M30

Result:

circle.jpeg

any help is greatly appreciated.
Thank you
Robbie

Attached Images

• circle.jpeg‎ (39.4 KB)