Comptometers Part 2

Following on from earlier posts about Comptometers – we have been donated this incredible machine which was rescued from a skip direct from the Standard Triumph works!

Standard Triumph Comptometer
Standard Triumph Comptometer

This particular example is a Sumlock 912S and was built between 1950 and 1960*. Made by Bell Punch Co. Ltd. in Britain, distributed by Sumlock Ltd

It is a Sterling Currency Calculator. It is a model 912/S where the 9 denotes the full keyboard (keys up to 9), the 12 denotes the 12 columns of keys, and the S denotes a Sterling currency version.  The Sterling element refers to this machines ability to calculate pounds, shillings and pence and it would have been used regularly up to 1971, whereupon the UK converted to the current decimal system.

Bell Punch Company Ltd
Bell Punch Company Ltd


330 mm x 315 mm x 135 mm (13″ x 12.5″ x 5.5″), 7 Kg (15.5 lbs).
This incredible mechanical machine still works – Fascinating!


* Some sources date this machine to the 1940’s

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