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I purchased this machine in August 2012 from an online auction site. It had obviously suffered from a hazardous storage environment, since oxidation in its cover caused extensive damage to the painting. Inside, I realized that liquid has probably been spilled over the keyboard, since there was a big stained area and superficial oxidation in the front section of its base plate. Some rubber fixtures were also degraded. A pair of rollers at the back, used to slide the 7.5kg machine on top of an office desk, was practically molten. I replaced the rollers with wood. I also repainted the machine, trying to follow the original colors as captured by images of other machines found online. A thorough disassembly, cleaning and reassembly was necessary to restore the machine to working status, since dried out oils and greases from the 1960s seriously hampered its mechanisms. Apart from the deteriorated rubber fixtures, no other parts were missing or damaged.

In reassembly, I installed the main rotor before installing the carry rotor, as the photos below show. In retrospect, I should have installed the carry rotor first. I did that with the Facit 10-04 a year later, and it was much easier to find the correct synchronization.

From the serial number, it is possible to determine that the machine was manufactured by Facit at Atvidaberg, Sweden, in 1963 ( details here). A sticker found on the bottom indicates that its last revision by a technician took place in December 1969.

According to Facit's 1968 price list, a CM2-16 calculator was sold by 870 Swedish Crowns, which converted to about US$ 174 at the time. This corresponds to about US$ 910 in 2012 (ref). The CM2-16's electric counterpart, the CA2-16, cost almost four times as much (and weighed twice as much). A C1-13 went for 15% less, about US$775 in Sweden. In 2013, credit card-sized solar calculators can be purchased for US$3. They weigh about 20 g, while the CM2-16 weighs about 7.5 kg.

Have a mechanical calculator stored somewhere, and want to get rid of it? Send it to me!

Disassembly, cleaning and reassembly of a 1963 FACIT CM2-16 s/n 1042585

Disassembled parts

Basic frame, my disassembly limit

Rotor lock mechanism

Auxiliary keys

Division mechanism and position indicator

Back transfer mechanism

10-block keyboard

Main rotor (input register)

Carry rotor

Counter and accumulator registers

Finished, new painting

As purchased, in August 2012

More about this machine

Operation

Inside views

FACIT CA2-16, an electrical-driven version of the CM2-16

The evolution of FACIT calculators

Operation Manual of the Facit CM2-16 (in German)

Video: how pinwheel calculators work