First really successful PCB milling

Thread Starter

spinnaker

Joined Oct 29, 2009
7,835
I have been struggling in getting milling PCBs just right. I just couldn't get the depths right and the isolations between the traces looked ragged and looked like they were milled.

The main problem, I think was getting a truly level board. Even milling a flat pocket does not give a flat surface as there are always imperfections in the flattest of PCBs.

I ran across some software called Autoleveller which modifies your gcode to add probing gcode. When the code rns on your machine, it probes every 5 millimeters (or the distance you set). It then adjust you z axis to allow for board imperfections.

I used Diptrace to design the board. The then exported a gerber file of the bottom traces and a N/C drill file for the holes. I imported these files into Flatcam which produces the raw g-code. I then loaded the raw g-code into Autoleveller and produced the leveled code. That code was loaded into LinuxCNC and run on m machine.

Here is the outcome. I manually cut the outline myself and think I cut it too close. I really should have allowed the code to cut the board. But it is only a prototype after all.

I am pretty impressed with how the traces and isolation turned out. I don't think I could have done better with the toner transfer method.


upload_2017-1-11_20-38-7.png
 

nerdegutta

Joined Dec 15, 2009
2,682
Great work!

What type of drill bit did you use? Picture? What are the width of the trace and the isolation?

Looks really good.
 

cmartinez

Joined Jan 17, 2007
7,520
I have been struggling in getting milling PCBs just right. I just couldn't get the depths right and the isolations between the traces looked ragged and looked like they were milled.

The main problem, I think was getting a truly level board. Even milling a flat pocket does not give a flat surface as there are always imperfections in the flattest of PCBs.

I ran across some software called Autoleveller which modifies your gcode to add probing gcode. When the code rns on your machine, it probes every 5 millimeters (or the distance you set). It then adjust you z axis to allow for board imperfections.

I used Diptrace to design the board. The then exported a gerber file of the bottom traces and a N/C drill file for the holes. I imported these files into Flatcam which produces the raw g-code. I then loaded the raw g-code into Autoleveller and produced the leveled code. That code was loaded into LinuxCNC and run on m machine.

Here is the outcome. I manually cut the outline myself and think I cut it too close. I really should have allowed the code to cut the board. But it is only a prototype after all.

I am pretty impressed with how the traces and isolation turned out. I don't think I could have done better with the toner transfer method.


View attachment 118493
Beautiful work, man... I need to get myself one of those PCB CNC engravers... I'm under the impression that two-sided boards are easier to make that way!
 

Thread Starter

spinnaker

Joined Oct 29, 2009
7,835
Beautiful work, man... I need to get myself one of those PCB CNC engravers... I'm under the impression that two-sided boards are easier to make that way!
I have not ventured into double sided yet but I think the way it works is to drill a reference hole. And then you have a peg in your spoils board so you have something to line up on the flip.
 

djsfantasi

Joined Apr 11, 2010
7,914
Yeah, the board could rotate around one hole. Two reference holes define a line from which all other points could be referenced. Note that in three dimensions three points are necessary.
 

cmartinez

Joined Jan 17, 2007
7,520
Yeah, the board could rotate around one hole. Two reference holes define a line from which all other points could be referenced. Note that in three dimensions three points are necessary.
A three dimensional PCB is something I'd like to see! (and I mean other than just laying 2D boards on top of each other... or course)
 

cmartinez

Joined Jan 17, 2007
7,520
I believe people do it with one but two would be better.
I always use two. Because using just one would imply using one of the PCB's edges as a reference for alignment. And (at least down here) FR4 material that one finds at the store is usually cut from larger pieces, and those cuts are seldom well-squared.
 
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