John Harrison RAS Regulator 'Replica' - Video 12 of 13

A pantograph and wooden template arrangement was used to engrave numerals onto three separate dials for hours, minutes and seconds. The 'handwriting' is a reproduction of that displayed on Harrison's regulator dials.

I should emphasise that the dials in the video are not entirely finished : further polishing is required, using progressively finer abrasive papers and paste. They may eventually be 'silvered' (chemically coated with a very thin deposit of silver). Final balancing of the hands and hour dial will also be necessary, in order to eliminate inconsistent resistance to rotation, which would otherwise adversely affect timekeeping performance.

Precision regulators almost always end up with weird and wonderful dial configurations and Harrison's masterpiece is a good example. The objective is to minimise friction (and the associated, inevitable inconsistencies) throughout the movement train ; that is achieved, amongst other things, by reducing the number of wheels and pinions to an absolute minimum. A consequence of such an approach is an inability to drive concentric hour and minute hands : the penalties to timekeeping precision would be too significant

Of course, weird and wonderful doesn't necessarily mean ugly and, in this case, it could be argued that the result is exceptionally beautiful.

Further details at http://soptera.blogspot.com and
http://www.hsn161.com/HSN/Heskin.php
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