Recycling a failed power supply unit

In those warm summer afternoons, when it’s 35 °C+ outside, a failed PSU is a treasure, not junk: a silent, 12V fan and a mouldable metal case which easily turns into a fan stand. 😀


Overcoming Fear: Dissasembling a Netbook

CAM01148Five years old and my Asus Eee 900 fan was telling me in no subtle way that it was about to die. Based on previous experience, I thought that a drop of general purpose lubricant in the fan’s bearing would breath new life into it so I went to fetch my screwdrivers and started disassembling the little machine.

It took about 2 minutes for me to realise that I might have been a bit hasty. Continue reading “Overcoming Fear: Dissasembling a Netbook”

DIY: Bicycle Camera Stand

Bicycle camera stand material
Bicycle camera stand material

In order to be able to communicate better what driving a bicycle in Zagreb is like, I have long been toying with the idea of building a simple bicycle camera stand. Since spending a few months assembling a 3D printer like the Prusa to be able to print out the camera stand seemed just a little bit excessive, I opted for the more down-to-earth, nuts, bolts, scissors and pliers approach.

These were my design goals:

  • very cheap parts
  • very easy to build
  • robust enough to prevent damage to the camera

I focused on these because I wanted to allow others to easily copy the design if they want. Along the same lines, I assumed that a good number of people now have a phone with a usable camera which they would be willing to use. It makes a lot of sense, given that even my 3 year old phone has a 640x480px@30fps camera, a reasonable power supply, more than enough internal storage for footage, is light, small and all that for about 50€ second-hand.

Continue reading “DIY: Bicycle Camera Stand”

DIY: Weaving a Strong e-Bike Wheel

The wheel on the micro-carpenter table
The failing wheel on the micro-carpenter table.

Like any other emerging technology, electric bicycles have their rough edges to iron out. With hub motors, one of the issues that might occur is wheel strength. Namely, my rear wheel came with the standard spokes you find on most bicycles, only shorter because the motor makes the hub wide. In my case, the motor weighs about 6-7kg, so the problem with using such spokes is that the motor gives them a heavy beating and they often snap. Although the motor represents a very small part of total weight (6kg, vs. 110kg bicycle + driver), this weight is directly hung on the spokes and there is very little amortisation. If you’ve ever chopped wood with an axe and the axe gets stuck in the log you’re chopping, you know that if you turn the axe upside down, the sheer mass of the log splits the log when the axe lands. That is (more or less) the effect the electric motor has on the spokes. Continue reading “DIY: Weaving a Strong e-Bike Wheel”