"A Replica Musical Clock"

I received the following article from a friend in Australia. He didn't want to start a blog and so I offered to post it up for him.

A Replica Musical Clock by Derek Deane

I bought the original Organ Clock (circa 1780) in the UK just before coming to Australia, for £5, and have been carting it around with me ever since.

It was not in good condition - there were no pipes, weights, chains, pendulum and , worst of all, no pins or bridges on the barrel.

Two years ago I bought a computer and got on the web, thinking that I could find some help in restoring the clock. I had some success but was unable to find anyone who could really help. I tried several museums in Germany but the language barrier was the problem.

I decided I was doing more harm than good taking it apart and putting it together again and, not being any further advanced with the restoration, I thought the best thing to do was to make a copy. In that way I could learn more and not do any damage to the original.

The first thing I had to do was to find some good timber and then I remembered some 6”x 1” I had put in the roof space of my house some twenty years back.

Now the temperature of that space in the summer months can reach 50 degrees C, so I figured that it should be well seasoned by now and sure enough it was perfect for what I wanted.

The timber was an Australian hardwood, known locally as Mountain Ash (Eucalyptus Regnans) which grows to a height of 300 feet in the ‘high country’ in the State of Victoria.

I used this to make the frame and the arbors of the movement.

The next thing I needed to make, were the thirteen gears. At first I thought of having them made professionally but the cost was too great. Talking to a friend who is a model engineer (and also a member of the Australian Mechanical Organ Society) I was convinced by him that I could cut them myself.These were made from 1.5, 2 and 3mm brass and cut using my lathe. This was the longest job to do.

The smallest gear had twelve teeth and the largest had ninety six.

Finding chain was just about impossible here in Australia, so I decided to use rope on all three trains and this worked out well. I am still trying to make the weights but this is just a matter of ‘trial and error’ to get them correct.

I made the dial from  1.5mm sheet steel as per the original and had it painted professionally. I am very pleased with the end result.

Having made the clock movement and got it running satisfactorily, the next job was to make the barrel and to ’pin’ it with the six tunes. I made a rough jig using a wooden frame and half inch copper tube which turned out to be accurate enough for the job. For the ‘bridges’ and ’pins’ I used 0.75mm brass wire and flattened it in a set of rollers to a width of 0.8mm, that being the width of the tips on the ’keys’. Each tune took me about six hours to complete.

The ten pipes were made from Kuri Pine, a New Zealand timber which was once in an old house here in Bombala for 60 years or more , hence nicely seasoned. After lots of experiment, I decided on a pressure of  ¾“ WG for the ten pipes which were tuned to G, G#, A#, C, C#, D, D#, F, G, G#.  These were the notes needed for the six tunes I had chosen:-

1. Baa Baa Black Sheep

2. Three Blind Mice

3. Oranges and Lemons

4. Here we go round the Mulberry Bush

5. Hickory Dickory Dock

6. The Grand Old Duke of York

I seem to remember that the person I bought the clock from told me that it came out of a large house and that it used to be in the children’s nursery, so I thought these tunes would be appropriate.

The bird in the dial I carved from the same wood that I used for the barrel - Jeluton. This is an Asian timber used mostly by wood carvers as it cuts easily both with and across the grain. Inside the bird is a mechanism which is worked from the lifting of the keys by the barrel bridges. This causes the bird to open it’s beak in time with the music. It also turns left and right alternately when the music plays.

Being retired, I do not keep a note of the time taken to make this project, but at a rough guess, it would be approximately six to seven months.

Posed by Derek Deane,  Bombala,  Australia.