Rosie's Horizon Clock

Another clock design for you to have a look at. My design is very different to James' who has posted below so it's good to have a preview of the variety of clocks that will be on show in 2015.





As you can see, the dial is not in any way a typical dial; it has many extra features that I shall explain as I go along, but the main idea behind the clock is that there are two hands which each point to either the sunset or sunrise. Only one hand represents the actual time and travels between the sunrise/sunset hands like the sun travels over the sky. I call it a 'Horizon Clock' as the two hands also depict the horizon as the sunrises and sets. The time in the picture above is about 10:12am on December 21st when the sun rises at just past 8am and sets at about 3.52pm.

Some initial sketches of how the clock will look at different points of the year

I was greatly inspired by how man measured time before mechanics and attempted to find a way to reconnect time keeping with natural cycles.

The train needed to be carefully calculated to begin with as, to ensure the horizon markers moved up and down throughout the year, they needed to be lifted by a cam which turned once a year. The centre wheel only rotates once a day and so the lower train gears down to a a wheel which rotates once every 364 days (365 1/4 days is far to difficult to work with). The upper half of the train gears to a seconds pendulum.

The next job was working out what shape the cams would be in order to lift the horizon hands and bring them back down again:

To begin with I was very unsure of what the cams would  look like and how I could make them accurate

After a lot of maths and a lot of patiently working out sunrise/sunset times, angles and distances using the method sketched below I came up with the final shape.

The time of sunrise was converted to degrees. The distance was then measured from this point to the centre of the cam.

The final cam shape (for sunrise)

I was reassured that I was on the right track when I discovered that a clock made by Edward Cockey, which also shows sunrise and sunset, had similar heart shaped components.

Initially I wanted the frame to be seen through a glass dial so looked at some skeleton clocks for inspiration. I was drawn to simple lines with an architectural feel and did some sketches using the train as guidance.

 My first plate design  wouldn't have been strong enough...

 

...So I settled on a stronger, bulkier design after deciding that I no longer wanted a glass dial and so the aesthetic of the plates mattered less.

The dial and many other components were heavily influenced by a clock that I worked on earlier in the year which I wrote about in this blog

Whitehurst of Derby hook and spike alarm clock

I loved the style of the wall clock  and so my final design of the dial reflects this.

The dial will be made of brass with silvering round the edges and the numerals marker in wax. The first day of every month will also be engraved on the dial to indicate the time of year.

Before finishing this term and heading off for our summer holidays we were expected to present our clock designs with our inspirations and workings for materials, time management and costings. Despite having a final clock design, I think there will still be a bit of tweaking happening over the summer months in preparation for the making process which will begin in September. I am very excited to begin!