One of the realities of having your own workshop, is a never ending trickle of people with ideas and their problems, leading to your door. One of these people wanted to build a copper fountain. It was a double helix of 32 copper cups. Water was fed into the top one, which over flowed into the one beneath, which overflowed to the one beneath etc.. The unexpected pleasure was the sound of thirty two miniature waterfalls. I jigged up for cutting all the components, drilling all the holes at the correct angles and positions for the 180 degree helix. I also knocked together some jigs to facilitate the soldering together of the components. The end product was about seven feet high. End of problem ? .... well not quite because I started thinking !.
In order to get a nice clean 'pour' you need to have the right shaped spout for the flow rate. It is one of these things one can play with on a rainy afternoon and soon becomes addictive !. I started wondering about producing elements on a fountain that acted in a random manner. For example 'articulated' cups. These have a special shape with a fixed pivot point. When the cup is empty the center of gravity of the cup is such that it sits on the heel of the cup. As water is poured into the cup this center of gravity moves towards the toe of the cup and at some point .... suddenly tips out about two thirds of the water in the cup before resetting itself.
Magnets can also be used to achieve motion. For example a magnet has a certain holding power on a steel plate, exceed that and the magnet is pulled away from the plate. We only have to attach a cup on the end of a pivoted arm and hold the arm up with a magnet. When a certain quantity of water enters the cup the total weight is breaks the magnets hold and the arm pivots down emptying the cup. Without the weight of the water the arm pivots back up and the magnet re-locks it's hold on the arm again.
After thinking about this I re-discovered lots of simple mechanisms that could be used to create motion and interest in a water display. The water wheel is an obvious source of power and motion.
One commonly seen trick in water displays is the levitating tap. A clear plastic tube is fixed to the inside of the spout of the tap, which is turned off. Water is now fed up the tube and the water escapes inside the tap spout, forcing the water out of the spout to form a stream. The clear plastic tube is invisible inside the stream of water and gives the impression that the tap is supported in mid air .... by nothing.
I have always been interested in illusions and so I wondered if it were possible to create the illusion of water going 'uphill'. Now there are ways to do this using moving surfaces, but I wanted to try and see if it were possible, using the helix layout. The helix arrangement simply has one cup under the other so that the overflow from each cup pours into the next one down. So my aim was to make it work in reverse ..... the output of the bottom cup feed into the one above it and the output of that cup into the next one up etc., etc.. I have worked out how to do it and it is driving my mate nut's trying to figure it out.
In any water display, we have to use some means of getting the water from the bottom of the fountain to the top. The simplest way is to use an electric or mechanical pump. Most water displays only require a very low water flow rate of possibly less than a liter a minute, but has to have the power or 'head' to force the water up a pipe to the top of the water display or fountain. Fortunately small solar powered pumps are available from suppliers such as Bull Electrical, that have good head and suitably slow flow rates.
One thing that can spoil the effect of an outside fountain is the wind blowing water streams, so that they miss the cup below. Part of this problem can be solved by spout design and partly by shielding the display from strong breezes.
Water displays can be very attractive and a focal point. The 'music' that they make is very relaxing and works well in masking unwanted sound. In due course I will make up some diagrams and include photographs. If you have any of your own water projects, I would be only too pleased to exhibit them here.