The short version: everyone was right. Induction caused massive AC on the sensor data wire.

I added a makeshift low-pass power filter with a resistor and capacitor I had handy in my tool bin, and it solved the sensor issue.

Turns out, 25 meters of narrow gauge wire is a terrific antenna.

I need to do a proper measurement of the AC frequency on the power rail and design an RC filter to match it for the production design, but this is good enough for now.

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Trace paper is where I always start

At World Maker Faire last Sunday, an absolute highlight was being able to see Laura Kampf and Sophy Wong talk about design and making.

I sat with Alex Glow, and was totally thrilled with the presentation. I was especially happy when they showed their notebooks, because I, too, had documenting and sharing my sketchbook drilled into me in design school.

So that's why I'm so happy that I was able to find this photo of the most critical sketch for the Witch Lights, the paper copy of which is in one of about 6 boxes in my closet. This is where I started at one end of a roll of trace paper, and just outlined all the chain of components and elements I'd identified so far. That’s where I realized I could create a unified harness and LED structure with 3D printing.

When I started the sketch, I was considering using polypropylene chinese food containers for the junction boxes. They're recyclable, tough, water-tight, and inexpensive. But my experiment with a hole-saw and the conduit fittings had proved frustrating and laborious.

The conduit I had was 3 times the diameter of what I'd thought I was ordering at 2am the other week. But I liked the way I could make it form shapes in mid-air, and so here I was trying to lay out how using it would change the design.

Note on the left there’s an actual fitting for the harness. I had just found a solidworks model of these online, so I knew I could use my Solidworks assembly context skills to very quickly design hardware to fit it.

At the time I was thinking of printing lids for Chinese take-out containers.

In the upper left, you can see I started a marker sketch of a take-out housing, and then sketched a simpler, streamlined housing that allows the diameter of the conduit to say roughly the same all through the chain.

In the lower right: I figured out I could put sensors in the housings too, reducing another complexity

And you can also see the cable glands and 4-pin waterproof cables for the NeoPixels, which I had already figured out at this point.

It's so cool to find a moment where you pulled it all together and made a design decision that worked out. I'm excited about this!

So yeah... this is basically how I draw. It's not the best. But it gets the idea across I hope.

Next up: building an enchanted notebook so I have shots like this of all my in process work. Because I’ve lost another goddamn notebook.

I went to Firefly 2018 as DevilBunny, the Mad Which of Firefly.

And now I'm home, exhausted and sick after the hardest Firefly I've ever had in five years.

Show above: The Which's Familiar, Samhain, on the bin containing Witch Lights 2.

I have stories, pictures, and video, which I plan to release as video podcasts on this feed, featuring video of the Witch Lights test setup in my back hard at home, and my voice as I tune the animation, and tell stories of this and past Fireflies.

If there's any interest, I'll have friends on to tell their own stories.

But until then, I'm recuperating. Suffice it to say: despite major difficulties, the Witch Lights were in place and running in "Burn Night" celebration mode at the hour the bug burned. Which counts as making charrette at the last possible moment.

And that's only one thing among a week of an intensity I haven't known in... possibly ever? Certainly never without some form of accompanying trauma.

Anyway. I'll be back. But resting has to happen.