Today I continued my devolution from 21st-century science back to preschool arts-and-crafts by making a pop can pen, which is a cheesy version of a real thing called a "folded ruling pen". That's a very simple and surprisingly modern invention(1995) which allows really dramatically adjustable pen/brush strokes. Imagine a brush you could tune from 1mm wide to 20mm wide in the middle of a stroke.
Still figuring out how to use it. I don't think mine's very good, but it's all I've got until more nibs arrive in the mail.
I probably under-thought and over-engineered this Raspberry Pi mount. I thought it would be neat to either check the status of 3D prints or make time-lapse pictures of them.
It's part of my continuing trend to steal my son's Erector set as useful mounts for things. I made a mount for the large cable spool. This was also part of an attempt to organize my space. Right now, I'm not embarrassed to show you my workspace....
The best feature is the absolute mess of wires all over the place in the third picture.
My personal favorite is the USB cable draped over the microscope and the door of the armoire - the PC which controls the 3D printer is about 2 meters to the left. The plan of record is to move
I should invest some time into cable management, but stuff gets moved around often enough that it's not always worth the effort.
I finally built something I wanted to do for quite a while: Chua's circuit.
It's a chaotic oscillator, which, instead of producing something incredibly boring like a sawtooth wave or whatever, creates a monkeyfighting, honest-to-god strange attractor. In fact, it's pretty much the opposite of a boring, well-behaved wave: it never repeats. It never does the same thing twice, which is pretty crazy if you think about it.
After doing a compact one on stripboard which turned out to be a pain in the ass as I was looking for shorts and everything, I did it again on perfboard with lots of space and laid out like the circuit diagram:
I immediately got the double scroll after turning the knob, which was a nice surprise:
About half the parts are from old junk like broken TV sets.
The sound file below is what it sounds like hooked up to a guitar amp, the high-pitched beeps at the beginning and the end are produced when the circuit is not chaotic, at the start there is period doubling which happens when the sound becomes more complex and then it turns chaotic as I turn the potentiometer knob:
So, on a whim (and a sale this month) I bought an "art lens" kit from Lensbaby. This picture was taken with the Edge 50 optic, which at lower apertures produces a thin slice of focus through the image.
I actually have some plans of pictures to take with this, but for now I'm just goofing off with it.
Also I made a V3 of my flashlight cover, which I made hexagonal, but probably won't work nearly was well as the round version. (It's much more fragile.)