The PCB layout that ships with the tag pcb-prototype on branch master has been milled into copper in order to prove suitability. However, using that file for production purposes is not recommended. Several fixes were necessary.

worked PCB layout

This is a short photodocumentary of the hardware production process:

PCB milling has just finished

The copper board has been milled during an introductory workshop in the FABLAB Berlin.

PCB cleaned up

Cleaning the PCB is important, otherwise you will have to deal with dust located in the gap-routes when you want to apply clear varnish later.

Soldering difficulties on component side

Sockets and parts with a big footprint should not to be soldered to top layer pads, this turns out to be very difficult and tricky. For example, to solder an variable resistor, you will need to use a vacuum pump while pressing the part firmly onto the surface. When done, you are lucky if the pins are still connected. And note that for some reason drilling was not always centric.

How to solve soldering difficulties on component side

Top layer pads should be large, otherwise you will have to lever sockets or chips a bit in order to use their thin legs.

Assemblage complete

When the board is fully populated, don't forget jumpers!
Apply a clear varnish over all, but cover important contacts.

The PCB Prototype in action

It worked right from the start. What you can see here very well is the SPI-cable which uses distances for its wires, in order to prevent signal interferences. The target shown on the photo is a T500 motherboard.

Copyright: Copyright (C) 2017, 2018 Kai Mertens kmx@p.nosp@m.oste.nosp@m.o.net
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled: GNU Free Documentation License