These PCBs were made with the desktop CNC from Bantam Tools. The otherplan software because you can easily drag and drop your cad files. We designed the PCB in Autodesk Eagle and created a custom footprint for the QT Py. This was routed for a single-layered board and features pretty chunky traces.
FR-1 Single-sided PCBs
These singled-sided FR-1 blanks from bantam tools are pre-cut so they fit on the spoilboard.
To secure the PCB blank to the spoilboard, you can use double-sided scotch tape. I like to use wide tape because it gives you more coverage – just be careful the tape doesn’t overlap.
Secure to Spoilboard
The PCB is lined up with the lower left corner of the spoilboard. Material can be warped so I make sure to press down firmly and wipe the surface clean.
Endmill with the Fan Bit
The 1/32 inch flat end mill is my go-to tool whenever I’m milling PCBs. Using a fan bit keeps the dust away and it’s handy if you’re doing any sort of filming.
End mills are secured to the collet and the machine has a probing process that checks the tool z-height.
Four QT Py Heart PCBs fit on one sheet of FR-1 (127mm x 101mm). You can get the most out of your material by placing your boards closer together.
Use alcohol to soften up the adhesive from the tape. A squirt bottle is great for applying to the spoilboard.
Use a thin spatula or palette knife to pry the FR-1 sheet off the spoilboard. Ideally remove the whole PCB from the spoilboard in one piece.
Wipe the PCBs clean with alcohol using paper towels. Use Scotch Brite scuff pads to lightly sand the edges and surface.