Drums

 

All together we need a total of 225 drums. A few of these are used on various displays etc. and a few are held as spares. 180 are for our rebuild; allowing five drum variations per Letchworth Enigma. We initially made a batch of 25, first to prove that we are on the right track and to encourage those who had to put in considerable work to complete the rest. We are in the final phase of this operation and are just needing to complete the extra ones to complete our original number. Meantime we have sufficient to mount any known menu albeit not in some cases with all the banks populated.

The two images below are of our first drum.

drum5.jpg (96659 bytes)

 

Below is the 'brush' side.

More on Brush Supports

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Manufacture started with individual components.

Below is an image showing spun brass covers and main support discs. The covers were spun in Switzerland as arranged by Philip Bellamy. The covers came to us as just as blanks with a simple centre hole. Philip also arranged the tooling to drill the remaining holes. Members of our team then completed the drilling and finishing operations.

The main drum support discs were turned to inner and outer dimensions by Mike Hillyard from sheet material. Paul Kellar made a drilling jig for the complex hole pattern created directly from the original Tony Walden, AutoCad file. Members of the team then drilled all these discs.

We had all the brush pillars made commercially because of the large numbers and complexity. We also procured the very small 2-56 grub screws and 3-48 brass fixing nuts.

We are close to completing over 20,000 brushes. All the ferrules have been made and a very large amount of 0.008 inch diameter piano wire was cut up into one foot lengths. Jigs were  then devised for cutting and crimping the wire. This process although very time consuming has gone very smoothly.

drum1.jpg (17138 bytes)

Drums Continued

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