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5. Electronics production

This week I made a FabISP programmer. Mostly, followed the tutorials for putting it together, put it together, and had some soldering issues. Basically if you apply too much heat to the board the copper lining will come up, and you will be SOL for traces unless you get fancy with wires. Also with the wires - make sure you have some patience. Getting everything right with them can be time consuming and tricky.

I also learned how to get the permissions set to use a Roland MDX-15 on my lab computer. How-to file is saved on that computer - will upload it here later.

UPDATE: I followed a linux tutorial about changing permissions. Due to the way things were working, I was not able to permanently allow for general users to access the milling machine through it. However, given the delicate nature of the stuff within the milling machine, I feel that requiring an admin permission is ok. So in summary, I was able to change the permissions to allow admins to use it!

The tutorial for this week regarding how to go through and use everything was useful while at the lab in Waltham. The old mods interface was pretty straightforward to figure out, too, for my lab in Roxbury.

I did find it very helpful to use an ohmmeter to check all the connections as I went, to make sure things were in electrical contact, and that there were no incidental shorts. Yay!

Pictures

Going top to bottom: - End mill did not fully go through copper. I did 3 on one piece, and as you moved left to right it got worse. Could either be issue with bed uniformity or adhesion to the sacrificial layer. If it wasn’t so bad, cut just cut a couple (for reference) - A couple things to solve the above: Level bed with mill - time consuming. Adjust the depth going to slightly more - good temporary solution, but doesn’t address underlying issue. Put on poorly - take it off and see if the adhesive folded or anything. Quick check, but might be tough to gauge. I did the check the tape thing, and redid it. That seemed to fix the problem for me, but YMMV. - Pad came off from mini usb, so board is shot. Need to be more efficient in applying solder and not destorying the adhesion between the copper and the underlying material. - Trace started to come off going through the diodes to the ground. Dammit! Almost there, but ultimately nothing. - Big mess off solder and crossed lines on the 2x3 connector, can’t clean up with braid or suction. Poo! Diagnosed via multimeter connecting multiple paths that should not be connected.

But eventually, yay! It works! I programmed it using Greg Buckland’s programmer, following the magic steps of making sure the right programmer and clock are selected, make clean, make hex, make fuse, and make program (while in the proper directory!).

No dogs this week.