We know, we know. Getting PCBs professionally fabricated anymore is so cheap and easy that making them in-house is increasingly becoming something of a lost art. Like developing your own film. Or even using a camera that has film, for that matter. But when you’re in Brazil and it takes months for shipments to arrive like [Robson Couto] is, sometimes you’re better off sticking with the old ways.
[Robson] writes in to tell us how he decided to buy a ~$150 CNC “engraver” kit from an import site, in hopes that it would allow him to prototype his designs without having to use breadboards all the time. The kit turned out to be decent, but with a series of modifications and a bit of trial and error, he’s improved the performance significantly and is now putting out some very nice looking boards.
The primary hardware issues [Robson] ran into were in the Z axis, as some poor component selections made the stock configuration wobble a bit too much. He replaced some flimsy standoffs as well as swapping in some bushings he salvaged from dead inkjet printers, and the movement got a lot tighter.
Despite the fact that the version of Grbl flashed onto the engraver’s cloned Arduino Uno supports Z leveling, it’s not actually enabled out of the box. [Robson] just needed to add some extra wiring to use the spindle’s bit as a probe on the copper clad board. He also went ahead and updated to the latest version of Grbl, as the one which ships with the machine is fairly old.
He wraps up the post by going through his software workflow on GNU/Linux, which is useful information even if you’ve taken the completely DIY route for your PCB mill. If you’d like to know more about the ins and outs of milling your own boards, check out this excellent primer by [Adil Malik].