Hello Daedelus,

I just bought a CNC3040T machine that could really make use of your software. I went to your site but I could not find the download link for the software. Would you please check that or post the direct link here?

I am currently using SprintPCB layout software that outputs Isolation files in HPGL. I then run them through another program to convert the HPGL to Gcode and then make a couple of edits to keep LinuxCNC happy then I can route the board. The results have been dismal thus far, all attributed to the the CNC hardware. Z depth is now the most critical one. I don't think I can solve it in any way without your software.

I do have one question: How does your software handle a double sided PCB? SprintPCB will generate one file to handle both sides but it puts a comment in the file to prompt to flip the board.

I probably have close to $1K USD invested and I have not been able to make a single part!.

Thank you for your interest.

Sam



Quote Originally Posted by Daedelus View Post
Dear CNC PCB guys,

Inspired by the ideas from Poul-Henning Kamp [Height probing for PCB isolation routing with Eagle/pcb-gcode], I have created software to probe the surface of a blank piece of copper, then use the probed coordinates to adjust the Z height during the milling process, i.e. the tool height varies according to its X, Y position. I have also filmed the first test and also produced 2 identical circuits; with and without the autoleveling software running to demonstrate the results. Currently, I have tested with linuxCNC (it may or may not work in Mach3 at the moment, but definitely will in the future) and the GCode was originally generated with pcb-gcode. The software itself accepts a GCode file as input and outputs an optimised autoleveleled file.

I know there is an autoleveler for PCB-GCode already but I couldn't get it to work and my software should work on any gcode file produced from any isolation software and should be easy to use too.

Why wouldn't the copper be level?

  1. Table might not be level relative to the tool
  2. Blank copper might have significant flex


Why is this a problem?

  1. Some areas of your board are lower than your Z zero while other areas are higher, leading to deep cuts in some areas and shallow cuts in other areas
  2. Occasionally, a very small ammount of the tip will break off if there is a lot of pressure from a deep cut. Then your tool won't touch the surface at all and you will need to re-touch-off Z and re-run all or part of the code
  3. Bits and boards are wasted


To demonstrate this problem, here is a pic of a non-autoleveled circuit board:

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There is a huge area in the bottom left which is completely missing. This is with a leveled table so only the board flex is an issue here.

This is the exact same 100x80mm circuit with my autoleveling software in operation (same pcb-gcode settings, same method of fixing the board down etc.):

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As you can see, this is much more consistent. The traces are thin but thats due to the settings in pcb-gcode and Eagle, not the autoleveler.

I also filmed the whole autoleveled milling process. Here is the cut down video:



Where can I get the software? As soon as I make a website to stick it on I will add a link. Assuming there is interest in this project?

Happy Milling :),
Daedelus.