Odhner 12
Very peculiar, this small capacity "Alien" series machine from Odhner. Why ? Well, because I'd never seen one with fast clearing. The Odhner model overview table however, does indeed mention it, it is an Odhner model 12 - fast clearing and no +/- change. I've never seen one before, not even a picture, it isn't on rechenmaschinen-illustrated, or in the ifhb's Rechenmaschinen-Lexikon. The only one known is in the Turku museum in Finland, and a picture was uploaded to rechnerlexikon by Timo Leipälä. I must have been very lucky to find it!Of course, there's a story attached to it. It came from Sweden, where it was sold by a man who did not want to send it abroad, and then changed his mind halfway through the auction. He does not speak or understand any English (luckily we have google translate) but he also seemed to have some issues communicating in general. When the box arrived, I knew immediately there was no way in hell the machine had survived the trip in one piece.
And indeed, it hit concrete or something with the front of the cast-iron base, which shattered part of it. I filed a claim with the shipping company, but they got back to me saying that the seller/sender should do this instead. And then of course the shenanigans started in earnest... we're two weeks on now, and I have no idea whether anything, or what, is even happening. Luckily the fix was quite feasible and no permanent damage was done.
When the machine arrived, apart from the broken base, also the crank was stuck. This was due to the locking system for the pinwheels when a calculation is ongoing, being a bit stiff. There is a row of intermediate gears that has to move out of the way to uncouple the input control register, and at the same time this locks the pinwheels by shifting a toothed bar in a cutout in the central axle through the pinwheels.
I did get this mechanism to work for a while, but then at some point the entire thing blocked halfway during a revolution, and it was quite the conundrum to get everything apart. In addition, the reason for the problem seemed to be inside the pinwheel cylinder, and I'd never taken an Odhner pinwheel cylinder of this vintage apart.
After extracting it from the machine, I discovered the leftmost pinwheel had now lost its clicking action, and the bar for blocking the pinwheels was completely stuck.
I apparently could not take the cylinder apart from the left side. There is however a gear screwed to the rightmost pinwheel with three screws, which I took out. I then tried to unscrew the gear, and that didn't seem to work either. So then it was the ifhb to the rescue, where on the Schwarzes Brett, Johann Krannich was kind enough to inform me that indeed the gear should in fact unscrew (while grabbing it in soft jaws in the vise - or lead). And with a tiny bit more violence, indeed, it did, the whole thing came apart, and it turned out that the issue was (as it nearly always is) - hardened grease. This was cleaned out, the cylinder reassembled, and all was hunky dory. Unfortunately during all of this process, I did not have my cell phone with me, so there are no pictures.
The only issue when I had juggled everything back together (the timing between the carriage movement safety, the pinwheel cylinder and the input control register is a bit of a nightmare with only two hands), it turned out to be that the direction safety, a fine toothed gear with a gap in it to allow the pendulum to change direction when the crank is in its zero position, was mounted 180° apart from it normal (and functional) orientation. Oops.
Did that mean an hour's worth of work taking everything back apart ? Luckily, there was a hack that allowed to tap out the locking pin and simply rotate the gear in place around the axle, then tap the pin back in. No disassembly required, and only 5 minutes work. Phew!
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The repairs on the base were continued and it received a lick of paint too and a polish, the domed washer on one of the rubber feet was replaced and the bottom plate and feet mounted back, and this extremely rare machine is as good as new.
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Some pretty pictures to round it off:
And then some pictures with its siblings - the Odhner 6, with fast clearing and no input control. It turns out that it is very easy to construct your own Odhner 12 from an Odhner 6 and an Odhner 14 (if you can find one), should you wish to do so - the carriages are identical and simply exchange. It must have been expensive from the factory, because the Odhner 6 is quite common, but the Odhner 12 and 14 aren't. The models 18 and 20 with input control register are much more common than the 14, and they were not made with fast clearing at all.
...and the Odhner 18, with input control, but without the fast clearing.
