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PCB Design (PCB Editor)

Route traces, check design rules (DRC), export a 1:1 PDF and Gerber files to manufacture a real board.

Exporting Files: 1:1 PDF (Iron-On) and Gerber (Send to Fab)

Both buttons are in the left panel, Export tab (next to "Tools").

Export tab with the Export PDF and Export Gerber buttons

Export PDF

  1. Click Export PDF.
  2. If there are still crossing errors: "Export blocked: N trace crossings remaining. See 'Auto-Fix Errors' to find where, then add a jumper manually or reroute the wire."
  3. If not blocked, the "Export PDF 1:1 (mm accurate)" dialog has:
    • Mirror (enabled by default, "REQUIRED for heat-transfer ironing — toner side faces the copper").
    • Page 2: silkscreen + drill centers (not mirrored).
    • Crop marks at the 4 board corners.
    • A warning if the board is larger than A4 ("the printout will be cropped, not automatically scaled down").
    • A note: "When printing: choose Actual size / 100%, and turn off Fit to page. Measure the 50mm calibration ruler on the printout before ironing."
  4. Click Download PDF.

Result: a file pcb-<project-id>.pdf is created, drawn to an accurate 1:1 mm scale (not a screenshot). Page 1 is the mirrored black-and-white version, including the outline, copper traces, pads/drill holes, crop marks, and a 50mm calibration ruler + a 10×10mm reference square to re-measure before ironing. Page 2 (if enabled) is NOT mirrored, used for drilling/assembly alignment.

Checking the printout before ironing the board

Before actually ironing, always check the paper printout first:

  1. Use a ruler to measure the 2.54mm header spacing, the spacing between the two rows of ESP32 pins, and the board's overall size on the printout — even a 2–3% deviation caused by the printer's "Fit to page" setting can make headers not line up with the real components.
  2. Place the real components on the paper: check whether the ESP32 pins, relay, LED, and terminal align with the correct pads, and whether the USB port faces the correct direction (especially important for ESP32 DevKit boards).
  3. A laser printer gives the best toner-transfer results; a direct-thermal receipt/thermal-paper printer doesn't produce a toner layer, so it should only be used to print a drill-alignment template, not for actually transferring the real circuit.

Export Gerber

  1. In the Export tab, click Export Gerber.

Result: a file pcb-gerber-<project-id>.zip containing pcb-F_Cu.gbr, pcb-B_Cu.gbr, pcb-Edge_Cuts.gbr, pcb-F_SilkS.gbr, pcb-PTH.drl, README.txt — upload it directly to JLCPCB/PCBWay. This is also blocked if there are still crossing errors.

Example

Making the "Room Temperature & Humidity Monitoring Station" board at home using the toner-transfer method: check that DRC is clean, click "Export PDF", keep Mirror enabled as it is by default, download the PDF, print at Actual size 100% on a laser printer, then measure the 10×10mm square on the printout with a ruler before ironing it onto the copper board — if the square measures exactly 10×10mm, the whole layout is guaranteed to be at an accurate 1:1 scale.