This site is devoted to my collection of (mostly) mechanical calculators and adding machines, dating from the middle part of the 20th Century.
As with all collections, it started in a fairly random fashion, but it quickly began to form itself into some quite well-defined groups:
- An example of every Odhner 100 Series machine (except the 135, unless anybody out there would like to donate one to me!)
- Examples of Odhner machines from different time periods;
- An example of most general types of Facit machine;
- A Felt and Tarrant comptometer;
- British comptometers from different time periods;
- An example of each of the Contex Model B half-adders;
- Some Monroe machines;
- Various other machines;
- Some user guides and other documentation picked up along the way;
- One of each type of Curta.
- Some examples of the large electro-mechanical machines;
- A couple of examples of the type of electronic machine that brought the whole thing to a crashing halt.
One of the main considerations in building the collection was cost. Calculators from the 1950s and 1960s are cheaper to obtain than those made in the pre-war period. However, it has to be admitted that the older machines are more attractive to look at.
I have given an indication of the price I paid for each machine, noting that:
- This might sometimes have some connection with its value;
- The cost of postage can sometimes exceed the cost of the machine.
I prefer the machines I collect to be in full working order. Not all of them are in working order when I get them, but I can strip the Odhner machines down far enough to fix them – sometimes a bit of appropriate bending is all that’s necessary. Physical condition is less important – in fact I quite like the patina associated with use (as opposed to the corrosion of neglect). The Odhner machines in particular look attractive where the paint has worn away to reveal the brass metal in the vicinity of the setting levers – this is evidence that the machine has had a long and useful life.
This site is not intended to be a technical reference – there are sites elsewhere that have addressed that matter more comprehensively than I ever could. However, there is some reference material on the site – the Odhner User Guide in particular is a useful introduction to pinwheel calculator operation.
The main purpose of the site is to catalogue my collection, with the addition of some commentary, in which a certain amount of bias will be evident. Other peoples’ opinions may differ from mine!
Mechanical calculators were never cheap, and were never household items. In the 1960s, a typical pinwheel calculator cost about £50, which allowing for inflation would be about £1000 today. A fully automatic machine such as the Facit CA 1-13 would have cost four times as much. Even relatively flimsy and cheaply made machines like the Contex would have cost about £25 (which corresponds to an astounding £500 in today’s currency).
A Felt and Tarrant comptometer or a Monroe calculator cost about $300 (£60) in the 1920s – this would be the equivalent of approximately £3000 today.
It is gratifying, though, that these antique machines, clearly built for a lifetime of intensive use, survive so well today. It is also gratifying that they can be obtained relatively cheaply today for the enjoyment of collectors like myself.
I’m always willing to talk to other collectors, so if you would like to leave a comment (even if you aren’t a collector, and have found this site by accident!), please use the following email address:
THE MACHINES ON THIS SITE ARE NOT FOR SALE