In my day job as a scientist and otherwise I have hand wound a fair number of coils. Winding by hand is time consuming and definitely falls into the satisfying but not interesting category of activity. Practically, it is hard to keep track of the number of turns (a typical coil may have of order 1000 turns) and it is tricky to maintain consistent wire tension. In short, the repetitive task of coil winding is a job for a machine.

So, I decided to put together a system to help. It's a work in progress but already proves to be a step in the right direction. The 'slightly automatic coil winding machine' consists of mechanical gubbins to hold the wire spool and bobbin; a motor to spin the bobbin; and a revolution counter. An arduino uno controls the speed of the motor and reads the revolution counter, outputting its value to a salvaged 4 digit display.