There are dozens of circuit board printers out there that lay down traces of conductive ink and ask you to glue down components to a fragile circuit board. This is a far cry from the old way of making PCBs, but these printers are going gangbusters, cashing in on the recent popularity of hardware startups and rapid prototyping.
People who think deeply about a problem are few and far between, but lucky for us [Arvid] is one of them. He’s come up with a way of creating PCBs with any 3D printer and steel rod. The results are better than anything you could make with a circuit board printer, and the technique is very, very cheap.
[Arvid] is using the traditional method of etching away copper, just some ferric chloride and a bit of time. How he’s masking the copper that shouldn’t be etched away is a unique process we haven’t seen before. He’s simply covering a piece of copper clad board with permanent marker, and scribing the parts he wants to be etched with a sharp steel rod attached to a 3D printer.
The G code for the printer was generated by FlatCAM, a piece of software made specifically for cutting PCBs with a mill. [Arvid]’s technique works so well that spindles and mills aren’t needed; only a sufficiently sharp instrument to scrape away permanent marker.
Thanks [Hassi] for sending this one in.





As you can imagine, a single spark won’t erode much metal. EDM machines fire tens of thousands of times per second. The exact frequencies, voltages, and currents are secrets the machine manufacturers keep close to their chests. [SuperUnknown] is zeroing in on 65 volts at 2 amps, running at 35 kHz. He’s made some great progress, gouging into hardened files, removing broken taps from brass, and even eroding the impression of a coin in steel.
scans of large objects (including people) come out looking noticeably faceted. [Luis] came up with a work-around that results in a much finer detailed scan. Instead of scanning an entire person with one scan, he would do 4 separate scans. Since each individual scan can support 5,000 faces, the resulting merged model can be up to 20,000 faces. Check out the comparison, the difference between the two scanning methods is quite noticeable. 