8. Electronic Production - Students¶
Carvera PCB Milling Workflow — Oliver Abbott¶
This documents the complete MakerCAM workflow for milling a PCB on the Carvera CNC mill. The process involves setting up the stock material, importing KiCad design files, generating three separate toolpaths (traces, drill holes, and board outline), then simulating and exporting the G-code.
Setup¶
1. New Project¶
Open MakerCAM → New Project → Select 3 AXIS
2. Stock Material¶
Stock Setup → Edit with the following values:
| Parameter | Value |
|---|---|
| Material | PCB |
| Length (X) | 127 mm |
| Width (Y) | 101 mm |
| Height (Z) | 1.7 mm |
3. Import PCB Files¶
File → Import → Import PCB (KiCad Gerber & Drill)
Import these three files:
| File | Purpose |
|---|---|
| Edge_Cuts | Board outline |
| F.Cu | Copper traces |
| PTH.drl | Drill holes |
4. Position the Design¶
- Zoom out and drag-select the entire design (dotted lines appear)
- Press M to open the Move tool
- Set Anchor to lower-left corner
- Set Location X: 6.000, Location Y: 6.000
- Click Close
Toolpaths¶
The PCB requires three toolpaths, run in this order:
Toolpath 1 — Trace Isolation (2D Pocket)¶
Removes copper around the circuit traces to electrically isolate them.
| Setting | Value |
|---|---|
| Tool | 2D Pocket |
| Start Depth | 0.000 mm |
| End Depth | 0.05 mm |
| Tool 1 | 0.8 mm Corn (listed first) |
| Tool 2 | 0.2 mm 30° Engraving (Metal) |
| Path Strategy | Parallel |
Selection: Show only F.Cu and Edge_Cuts layers. Select both, then click the outermost outline to deselect it — only the traces and inner outline should remain selected (dotted). Click Calculate.
⚠️ The 0.8 mm bit must be listed before the engraving bit.
Toolpath 2 — Drill Holes (2D Drilling)¶
Drills the component through-holes.
| Setting | Value |
|---|---|
| Tool | 2D Drilling |
| Drill Tip Start | 0.000 mm |
| Drill Tip End | 1.7 mm (full board thickness) |
| Tool | 0.8 mm Corn |
Visibility: Hide everything except the PTH.drl layer. Select all visible drill holes. Click Calculate.
Toolpath 3 — Board Outline (2D Contour)¶
Cuts the board out from the stock material.
| Setting | Value |
|---|---|
| Tool | 2D Contour |
| Start Depth | 0.000 mm |
| End Depth | 1.7 mm |
| Tool | 0.8 mm Corn |
| Strategy | Outside |
Visibility: Hide everything except the Edge_Cuts layer. Select the outline, then click the outside line to deselect it (turns solid) — the inside line must remain dotted. Click Calculate.
Tabs: Scroll to Tabs → Select Custom → Click Add → Place 3–4 tabs around the board outline. These hold the board in place during the final cut.
Simulate & Export¶
- Click Preview Toolpaths
- Check all three: Pocket, Drilling, and Contour
- Click Preview and verify the simulation looks correct
- Close the preview → Click Export → Select all three toolpaths → Export
- Save the
.ncG-code file
Full Workflow Reference¶
Download the complete MakerCAM workflow with screenshots: MakerCAM Workflow PDF