everhack Stuff I've been messing with, or just thinking about.

6Apr/116

more cricut pcbs: the sharpie method

Last night at the Hackerspace I tried a new way (to me) of doing PCBs on the Cricut. So far it looks like the most promising yet.

This time instead of trying to scratch off an etch resist, I'm directly drawing it on using a plain old mini Sharpie pen like a plotter would. I understand the Stadtler Lumicolor pen is also recommended.

I just now discovered this link that shows exactly what I need to try next as far as the pen goes: PCB Plotting

First I create the circuit design in Eagle:

-Then, in Eagle, run File->CAM Processor.
-Select Output Device EPS
-Click File and select your output file path.
-Don't worry about the offset and page size.
-Select the "Pads", "Bottom" or "Top", and "Vias" (it will complain if "Vias" is not selected).
-Click "Mirror" if you are doing the bottom layer.
-Click "Process Job," this will write the output file.

-Install a copy of Ghostscript & GSView, and run "ps2pdf [options] input.[e]ps output.pdf" to convert the EPS file from Eagle to a vector PDF.
-Fire up Make-the-Cut, and do "File->Import->Vector PDF File", leave "Import Strokes and Fills" selected, select your PDF file and click "Open".
-Select the imported image and click "Ctrl-B" to Break the circuit up into its pieces.
-Deselect all, then click on each of the four border lines and delete.
-Select all, and click "Ctrl-J' to Join the circuit back up into a single piece.
-Position the circuit on the cutting pad as needed.

-Load up your Sharpie in the tool holder and print a test piece on paper to verify positioning.
-Load up your copper in the machine. If you're running anything thicker than 0.01 you may need to raise the pen in the holder. I use double-stick tape or at least a fresh spritz of spray-tack.
-Print your design. I don't know how many coats are necessary, but I am doing two coats, one after the other. Don't use Multicut for this!!! It does each line multiple times immediately instead of doing the whole pattern completely and repeating it: This causes the pen to dissolve the previous coat and move it around a little.
-(optional) Put the board into the toaster oven just briefly to make sure the ink is fully dry.
-Etch!

Comments (6) Trackbacks (0)
  1. Will this work with double sided boards? I would assume I should toast it, before flipping it and drawing the other side, just to make sure it won’t smear. Do you have any tips for lining up the sides properly? Do you use the cricut cutting mat, or do you load the board in by itself?

    • I bet it would be pretty accurate if you taped some chipboard guides to the cutting mat to locate the board precisely.

      Alternatively I have wanted to try just doing two separate one-sided boards and laminate them together since my PCB stock is very thin anyways. A thicker double sided board DOES fit, but i’ve not tried etching one. My last attempt was with a fine point Sharpie which did not resist the etchant successfully.

      • What pen are you using? I was under the impression from your other posts that you were still using the sharpie. What pen have you found that gives better resist?

        • Sharpie only so far. Sorry, it’s the “fine point” one that worked in the photo above. It was the “ultra fine point” one I tried later that failed.

          Also, I got a multi-color pack of the fine points to see which color, if any, worked best. All other colors except black failed.

          So, my only success with the “Sharpie method” so far is with the fine point black.

  2. I’ve had some trouble mounting the sharpie. I don’t have the fancy milled holder you do, and I haven’t yet sprung for the ones you can buy online. My lame attempts to rig with tape or blue tac haven’t been stable enough. Have you considered trying to cut a stencil out with the regular blade, and then tracing through it with a sharpie? I was thinking if I used a good thick cardstock and a new blade that I may be able to get accuracy at least for something like a 32 mil trace on a basic board.


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