Minor Modifications to Water Feature #1

It took me a while but I finally got my water feature working - an excellent design by gzumwalt.

This remix is not a million miles away from the original design - just two of the parts changed slightly.

My version of the motor splash cover encloses the motor and is long enough to reach the bottom of the motor mount.

I closed the open reed switch shaft at the top of the cup in order to prevent the ingress of water.

Instructions

All of the non-printed parts were sourced in the UK. The magnets came via EBay, the motor is the "small motor" from Maplin (part number YG13P) and the reed switch, also from Maplin, is their "min reed switch" part number N30AN.

To form the latch, I cut a strip from an empty baked bean tin, folded it in half and then in half again, squashing the resulting strip tightly together with pliers - this was a good tight fit in the latch strip slot. One of my early failures came during some post assembly adjusting of the latch strip. I ended up snapping it off after bending it over as described by gzumwalt. I now have it standing proud by a couple of mm, enabling me to adjust its position by gripping it with pliers.

As I don't have a bench power supply, I tried a 3V mains charger to power the motor but ran into trouble after around 45 minutes of operation - the reed switch started to stick. This was possibly either because of some sort of welding effect or perhaps down to the reed contacts magnetising. (The current draw is quite high - something like at least 800mA at 3V). At one point the motor kept running even when the magnets AND the latch strip were totally removed, only stopping after a sharp tap on the reed switch housing shaft!.

I am now using a single D cell to run the motor as shown in the photograph but being battery operated, I am not sure how long it will last.

I am going to try putting a 2R7 3W resistor in series with the motor which should drop enough of the 3V from my mains adapter and reduce the motor current to something like the same as when using a single 1.5V battery. The 1.5V supply gives enough flow to fill the cup faster than water leaks out at the bottom.

Category: Gadgets