Tag Archives: progress

The Fan Controller Wrapped Up

Yesterday I found some time to put the fan controller in a casing. I used a very cheap no-name case with the dimensions 130 × 68 × 44 mm. First I drilled some 2.5mm holes into the lid, and fastened the Arduino board on it using M2.5 spacers. You see the bottom of the case in the photo – I mounted everything top down, because this simplified everything.

I experimented with the spacer size, until I found the right height, so the display is more or less at the same height as the case bottom. Next I put very small bits of double sided tape onto the corners of the display and put the case bottom on top of the lid. After removing the bottom, the exact position of the display was marked at the bottom with these double sided tape bits.

First I drilled four holes at the expected corners to see the position from the other side. Next I used a Dremel tool to cut the rectangle out of the case.

As usual: This was my expectation of the result… 😉


…, and this was the actual result:


No, seriously, I did not expect much. I just hoped the controller will fit into the case and I cut the rectangle at the right place. So, this worked out very well.

Building a Magnet Matrix

I did many tests with the Outmoded Sequencer how to use steel balls as switches. While this is working very well from the electronic point of view, one problem was the steel balls tended to fall of the PCB easily and roll under furniture.

To hold the small steel balls into place I am building a matrix of 8×8 neodym magnets. This magnet matrix is later mounted below the PCB, so there will be one magnet for each pad on top.

I am using these small, but very powerful neodym magnets. They have a diameter of 4 mm and a length of 5 mm. You can get this magnets, any many other shapes, from Supermagnete, they deliver the magnets to almost all European countries.


I started by using the holes in the PCB as a template to put marks onto a piece of plywood. Best is using a stitching awl, to create small holes. Next I drilled 64 holes with a diameter of 4 mm into the plywood.

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