Amphibious Thoughts

Etching your own two sided boards is quite a hassle. Apart from getting your foil print right,  having both sides in line and doing all the drilling, I found making vias with wires quite tiresome. The wires tend to leave the holes again whenever you try to solder something surrounding them. Especially when working with fine tracks (which is mostly the case with me, nowadays) this can be very annoying.

Luckly I found a forum where someone recommended to use small copper rivets for this. These rivets are only 0.6mm in diameter. Getting them into the holes is a bit tricky, but the its easy to open the other side with a small chisel. There exists, of course, also a special press for this, but the mindset of someone who actually will pay € 160,- for such a thing will forever remain unknown territory to me…

0.6mm is indeed very small...

Here, the rivets are used to conduct heat of a 3W LED to the back of the pcb.

There’s a project I’m working on (yes ANOTHER one, stay tuned, I’m serious with this one!) where I need to use a motor with around 20rpm that runs on 3-5V DC. I actually [found one] but it’s awfully loud. I opened a gear Motor that runs on 230V AC to see, why that one is much more quiet (only vibration).

My guess is that the DC motor produces more noise due to its higher pulse frequency and the brush contacts whereas the AC motor has no brushes and pulses with 50Hz, a frequency not amplified by its enclosure…

Coming closer to the point where the electronics for [Diskokugel] are settled, I start worrying about how to get sound and power into the turning thing. While with the sound I’ll most probably go for a wireless solution, with the power that’s highly unlikely. So I did an experiment with some ball bearings I had aquired for the (still pending) [cnc project]. I soldered wires to the in- and outside of the bearings to power a turning 1W LED. That resembled the setup I would have liked to use building a second [LED lamp]. Unfortunately even with a 1000µF capacitor on the LED end it wasn’t possible to keep the power straight. It might be helpfull to get the plastic caps of the bearings and apply a certain pressure on one side to keep the contact constant, but in general I abandoned the idea for high power connections. Considering the fact that the Diskokugel might use up to 200W at 5V there seems no way to keep the supply steady this way…

2 ball bearings on an axis as sliding contact