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Odhner's Arithmometer n░ 318

This very pretty machine is the 318th pinwheel calculator ever built in Europe (or the 333rd if you count Odhner's previous model and prototype too). As production started in earnest in mid-1890, it was probably sold at the end of 1890 or the beginning of 1891 by the Swedish agent and Odhner's brother in law Arvid ┼hlin, to a bank in Sweden. The Skandinaviska Kreditaktiebolaget was established in Copenhagen in 1863. They opened a Stockholm branch in 1876, at the Storkyrkobrinken 7. They must have decided about 14 years later that they could well use one of these new-fangled cheap Russian calculating machines by a Swede named Willgodt Theophil Odhner, and decided on the slightly cheaper model with smaller capacity of 11 digits, at 75 roubles, rather than splurge for the "big" one with 13 digits at 100 roubles. So one was ordered from ┼hlin, and duly shipped to Stockholm, labeled in Latin script for export. The machine was used, and judging from the state of it when I obtained it, used heavily and for a long time. Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

The main crank had probably been bent and hammered back into shape (but it is the original, complete with stamps), the machine received a crude repaint in black, including the crank, and the bearing for the crank handle was so worn out that the handle would flop around nearly uselessly. The right wingnut may have been broken at the same time as the main crank was bent, when the machine was dropped off a table or something. It was replaced with a Brunsviga nickeled wingnut dating from the early 1920's.

It is unknown until when the machine was used in the bank, but one of the bank's long-time employees took a liking to it at the end of the 1970s, when the bank was getting rid of their "old junk". He took it home, probably polished it up a bit, and kept it for 40 years. His son was finally clearing out, and that is how it then ended up with me, after I flew to Stockholm to pick it up.

Odhner 318 picture 1

Luckily, apart from the black paint all over everything, and the wingnut, all parts were original, including even the screws. Everything is stamped with a small "2", a large "4", and the initials "P.A.". So if anyone knows of a P.A. (or R.A. if the initials are in cyrillic) working at the Odhner factory in 1890, feel free to let me know, so we can find out who assembled and fitted this machine. Odhner 318 picture 1

Odhner 318 picture 1

In contrast to later machines, this one has a very small capacity of 9 x 6 x 11 instead of the usual later 9 x 8 x 13. It also has split bearings for the crank axle and the pinwheel cylinder, which were cast integral with the uprights no later than machine number 630.

Odhner 318 picture 1

Odhner 318 picture 1

I started with the most urgent repair to make the machine usable again - the split bearing for the crank axle. In addition to the hole being worn out and hourglass-shaped, also the screws holding the bearing together had lost much of their thread. After filing the contact surface of the split in order to make the hole narrower again, I could drill it out to a nice even and parallel 8mm. I put the original screws through a die, which made them usable again. This tightened up the crank nicely, and if you don't know about the issue (also the crank itself has wear, and turning that clean isn't an option), it isn't likely to stand out now.

Another thing that bothered me was the black paint on the carriage cover. I thought I could see faint traces of the original silver striping over the result register and of the dots over the counter register. I very carefully used paint stripper and wet-sanding to remove only he top layer of paint, so that what was left of the silver striping and dots would come out - as well as the wear pattern on the original paint. You can see why someone would have wanted to repaint it, but I still like it better this way!

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

The top cover may originally have been painted black, judging from the paint on the inside of it (note also how the copper medallion is a very thin stamping):

Odhner 318 picture 1

The final repair involved remaking the wing nut on the right side. Filing the Brunsviga wingnut was not an option, as the original wingnut is much closer to the carriage and there wasn't enough material. So I started to construct a wingnut from scratch, using the one on the other side (which is also repaired!) as a pattern.

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Creative way of broaching a slit (or how to misuse a lathe):

Odhner 318 picture 1

Silver-soldering the whole thing together:

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

...and there we are! Odhner 318 picture 1

Once that was done, and the whole machine was reassembled, it was time for some pretty pictures:

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

Odhner 318 picture 1

And finally, a family picture with its later relative:

Odhner 318 picture 1