I have a gcode file which specifies two straight cuts intersecting (and ending) at a point. This is correctly shown as two straight lines intersecting at a point in blue in the Mach3 tool path display. After a failed part, ( Corner radius too large) and subsequent detailed investigation I discovered that Mach3 appears to round off the angle between the two straight cuts with a small radius not giving the effect I required. On close inspection this is shown by the dotted green line showing actual tool motion in the tool path display. Effectively this corner/intersection now has a cut radius greater than the cutting tool radius. I had deliberately chosen the tool radius to equal the corner radius I was seeking.
Why does this happen and how can I get Mach3 configured to follow the G code lines exactly?