So to kick the project of I went to my friendly local woodturning supplier and bought a range of hourglasses or is it hourglassii, they ranged from a 30 minute version standing 150mm tall at a cost of £6.50 down to little egg timers 65mm high at 25p each.

The project has a number of subtle environmental aspects, in this world of the silicone chip this type of time measurement is battery free produces no emissions in its use, nor should it wear out and need spares.

So having made the initial material investment there is little or no impact on the environment from that point on however this form of interval timing does have limited applications. The 30 minute timer is a very useful class artifact for short tests or quiet working times.

The legs were cut from an old school science lab desktop then turned between centre's on an MT2 lathe. If you don't have a lathe that can turn between centre's then the legs can be replaced with three round dowels and the spheres and other shapes made in shorter lengths with a hole drilled down the centre. Then assembled much like a solid necklace. Cad cam should ensure that the joints disappear.

The top and the bottom were made from one piece of wood which was skimmed flat then a circle run with an Ovolo cutter then the four pockets were machined (Three legs and a centre hole for the pip on the hourglass). Then finally a straight cutter was run almost to half of the depth around the outer diameter to form the edge. The block was then turned over and the same actions repeated. Finally after removing the unwanted block pieces the two halves were carefully sawn and then sanded until flat. Finally a spray varnish was used to bring out the woods colour.