in calculating the tool path

[Grumpy Mike]

Do you know what post processor you are using on the Mac, and what it might be similar to on the PC? e.g. Mach3 etc. What are the dimensions and tool size?

Not sure what a post processor is in this respect. I have an arduino based controller that drives the stepping motors and takes in G-code serially. Replacator G can sometimes feed it with G code from a file but it doesn't work very well so I am writing my own.
I have CAD.py and CAM.py but can't get all the dependent packages to install. Like most software of this ilk the writers are more interested in the next fun thing rather than making it install properly.

OK on the levelling system, yes I have seen this technique but it can't compensate for the waviness of the PCB itself. Where as an automatic calibrated system would.

[irving2008]

OK on the levelling system, yes I have seen this technique but it can't compensate for the waviness of the PCB itself. Where as an automatic calibrated system would.

Not sure what PCB you're using but mine are pretty much flat - except the very cheap SRBP boards. what hold down method do you use?