Hello everybody, relative newbie here, just getting my plasma table going but I'm having a weird problem cutting circles.
Here are some bullet points that hopefully show my problem, and what works and what doesn't:
1) I have successfully cut a couple of outline irregular shapes.
2) This problem came to light cutting bolt holes in a shaped plate.
3) The hole circle cut starts accurately and then veers off with the circle then being cut offset from the correct position. With multiple holes to cut, the error appears to be cumulative, but the outer panel shape (rectangle with rounded corners) cuts correctly but in the wrong place due to the cumulative circle errors. The final object cut, looks a bit like a cedilla (e.g as in garçon in French)
4)I can cut a rectangle accurately.
5) I can cut a rectangle rotated through 45degrees accurately (ie both x and y axis moving at the same time).
6) I can cut a hexagon accurately.
7)I cannot cut a stand alone circle....doing this displays the same behaviour as described in point 3).
My CAD package correctly draws and displays circles
9) MACH3 displays the correct shape when I load the GCODE file (for any shape, complex or simple)
10) If I cycle through the GCODE with the scroll bar, MACH3 correctly displays the tool position superimposed on top of the predicted toolpath.
11) If I run the GCODE programme, I get the strange behavior described in point 3).
Clearly the movement instructions in my GCODE are correct because MACH3 displays the shape correctly and follows the shape with the scroll bar
Whilst my x and y steppers have encoders, there is no feedback to MACH3 so the fact that MACH3 displays the 'damaged' cut path when it runs the code, tells me that it has to be MACH3 doing something weird to my GCODE before sending it to the hardware. ie it's not backlash or sticky slides, it must be MACH that is doing this.
Does anyone recognise this behaviour please and know what the cause is?
Many thanks!