PCB mill



  • For a personnal project, I have to make a PCB and decided to add a mill tool to my CoreXY.

    The issue is that the virgin PCBs are, apparently, all warped… I am considering using the bed mesh to compensate but I was hoping that there would be a way to protect my Printer's bed mesh.

    Other than copying manually my printer's bed mesh, any idea?

    Thank you


  • administrators

    The heightmap.csv file can be copied off the the SD card or renamed as you like.

    The M374 command saves the current loaded heightmap to a file:
    https://duet3d.dozuki.com/Wiki/Gcode#Section_M374_Save_height_map

    You can use the P switch in G29 to save the new file with a different name:
    https://duet3d.dozuki.com/Wiki/Gcode#Section_G29_Detailed_Z_Probe

    The M375 command cna be used to load a height map with a specific file name:
    https://duet3d.dozuki.com/Wiki/Gcode#Section_M375_Load_height_map


  • administrators

    p.s. it will be interesting to see how you get on milling a PCB. 😄



  • Will do,
    Thanks you for the info, it's exactly what I was looking for.



  • I have been looking at G-Codes for CNC mill.

    The result is IMO less then ideal.

    Is there a G-Codes that I could add at the beginning of the G-Codes files that would reverse the direction of the Z-Axis or could I just enter M569 P* S0?


  • administrators

    Why do you need to reverse the axis direction? But yes that would work but would have the effect of reversing the direction for homing and all actions.



  • @Nylkos:

    For a personnal project, I have to make a PCB and decided to add a mill tool to my CoreXY.

    The issue is that the virgin PCBs are, apparently, all warped… I am considering using the bed mesh to compensate but I was hoping that there would be a way to protect my Printer's bed mesh.

    Other than copying manually my printer's bed mesh, any idea?

    Thank you

    Check out Russ's youtube channel, he has a delta+duet that he uses to mill PCBs and he made a video recently with the process - https://www.youtube.com/watch?v=z49pn_OVHLE - spoiler he used the mesh bed on top of the board.

    He also hangs out on here from time to time so hopefully he'll see your post.

    I mill PCBs occasionaly on my CNC machine and all I do is double side tape them down to a flat surface, so far I've not had any problems with flatness.



  • For milling a PCB, you do the opposite of 3D printing, instead of adding material, you remove it.

    My idea is simple, use a slicer that we know all how to use.

    You use 2 images, one with the entire trace of the PCB and one with only the holes. create a STL with the trace with a small depth (will have to be determine during testing) and add the holes (have to be careful not to damage the hotbed).

    To do so, we must start from the top and move down.

    Do I make any sense?



  • @DADIY:

    Check out Russ's youtube channel, he has a delta+duet that he uses to mill PCBs and he made a video recently with the process - https://www.youtube.com/watch?v=z49pn_OVHLE - spoiler he used the mesh bed on top of the board.

    He also hangs out on here from time to time so hopefully he'll see your post.

    I mill PCBs occasionaly on my CNC machine and all I do is double side tape them down to a flat surface, so far I've not had any problems with flatness.

    I will do. Once I get home tonight.
    Thank you


  • administrators

    Hi yes it makes sense,

    You could use you start gcode just for CNC files to do this.



  • @T3P3Tony:

    Why do you need to reverse the axis direction? But yes that would work but would have the effect of reversing the direction for homing and all actions.

    So to make sure everything is safe, I insert:

    • M569 P* S0 at the beginning after the homing procedure

    • M569 P* S1 at the end before the homing (if you have one).

    Thank you


  • administrators

    I'd depends how you want to use it. As it's a printer as well I should have homing and everything working with the axis I the correct direction and then just have the gcode "print" have the axis reversed.

    Hopefully someone with more experience with generating gcode for pcb milling can say how they did it so you don't need to use this "hack"



  • Hmm… could we have the Z-axis inverted solely for a specific tool?

    I assume that laser engraving would have similar requirements



  • Can we declare a tool with no heater and extruder, just a fan



  • I am getting ahead of myself, as my printer is almost done, but very interested in this.
    My question is, can I use 2 SD cards, one for the printer and one for the Milling?
    The latter is more like a cnc machine than printer and setting up a entirely different profile makes more sense to me. Laser engraving and PCB milling could be done with the same setup, just different gcode processing.



  • Yes, you could, has long that you have the same version of the software installed on both chips.

    Also, you might have to reinitialize them on occasion.



  • ok I did a few test runs, works great. Only problem is the PCB that I am trying to print is too tight… even a .2mm cutter is too wide (obliterate the trace).

    So I am changing to laser cutting for the PCB...
    Anyone knows if I can change something in my config.g files to run a 24V printer but to have an output of 12v at a specific pin?

    ATM, the laser is on constantly and I set up so when it moves the Z axis has to move 20mm which increase greatly the cutting time.


  • administrators

    Switching 12V power to the laser control module constantly is a bad idea. Most laser control modules have a TTL level input for turning the laser on and off, and you should use that.



  • The laser doesn't have a TTL, it's an old highschool project, a black paper burner / match lighter I made with a laser diode from an old CD burner, I had built a Step down 12V to 5V.

    I think that the simplest thing should be to build a new Step down for 24V to 5V and replace the older one.

    Thank you for you assistance.


Locked
 

Looks like your connection to Duet3D was lost, please wait while we try to reconnect.