If you've seen my latest PCB creation attempt, you'll know I'm ready to try and assemble my servo controller.
This is the ultimate test of my newly acquired PCB layout and fabrication skills. A good "looking" board will show its true colours when assembled... and I learned a few things.
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The fill (leaving most of the copper in place and only etching enough to isolate the required tracks) caused problems during soldering. There just wasn't enough clearance for my rough soldering skills. The minimal clearance gap used to allow tracks to weave between the 0.1" pitch pads was too small to deal with when soldering every pad. I dragged solder from pad to fill a number of times, and had to grab the
wick. I don't mind taking the extra care when needed, but on every pad? I'll increase this gap in the future.
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The physical clearances around header sockets and the ZIF sockets were a little tight... I should check such things a little more thoroughly. A sharp knife made them fit.
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The resistor lengths weren't checked... the carbon films I used were longer than the default I'd selected. They fit with a little inward bending.
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Repairing tracks is best done with a strand of copper wire laid & soldered along the broken track. A more elaborate method I tried (cutting a new track in the fill) only made things worse.

The assembled controller board
I fired it up, setting the current limiting on my adjustable supply very low to protect the circuit in case of a short. It didn't consume more than a few 10's of mA which was all good. I plugged the serial plug into my machine and powered it up. Boom! Fizz!
Nah, just kidding. The boot-loader showed its startup message and then it all appeared fine. I couldn't properly test it, since my ad-hoc board has all the encoder inputs & driver outputs wired in (as can be seen here), and this new board doesn't. My plan includes making another board (or two) which takes the 10 pin header from the controller and breaks it out into the 4 channels with separate connectors. Given the relative ease with which I've made this one... I'll pump out the extra board in no time.
I think its fair to say, that I'm a little pleased with myself.