[JackWilliam]

Hi,

I have a K40 laser cutter with a replacement circuit board from Chris' Circuits. I import DXFs into Mach 3. The DXFs have been drawn in Solidworks.


In Mach 3 I go to - file, import DXF. From the DXF I can then generate Gcode which excludes all Zs and includes Ms for turning on and off the laser. The Fspeed is default set to 1.000 (incredibly slow). SO I have to go through the code and change each of these to F1000 instead of F1.000. I can then change the feed rate in Mach 3 to get the speed right.

There was no problem for a few months, everything was working ok. However recently, everytime that I follow this proceedure there is the same problem.

I import the Gcode that I have created into Mach 3. For this example I am cutting a rectangle with rounded corners. The preview in the top left of the screen looks correct. I start the cycle and everything looks good on the first 3 sides of the rectangle. However on the last side of the rectangle the line is made too long and the last rounded corner does not meet up with the first edge. The Y axis has over run by aboutr 4 mm. If I then start the cycle again, Y0 has shifted 4mm. So then the rectangle is cut in a slightly different place. It over runs on the last edge again and the Y axis shifts by 4mm once again.

I have trouble shooted every way that I can think of, going through all the config settings and even reloading the XML file for the Mach 3 profile.
I think the problem is with Mach 3 and not the DXF. The reason for this is that the preview in Mach 3 looks correct, it just cuts wrong.

Can anyone help? Did I explain the problem well enough for you to understand?
Jack

[awerby]

It sounds like a problem with your machine, not with Mach3. It could be mechanical - when was the last time you cleaned and lubed your system? Is there any binding on any axis? Have you tried going a little slower?

Andrew Werby
www.computersculpture.com