the basic keys
The first trick with the actual typewriter was to get all the regular keys to produce letters. Shift, Space, and Enter I would worry about later.

A quick look at the underside of the typewriter provided the answer.



Every time a key is pressed, the "lever" is pushed down and connects with the "crossbar" (the other end of the lever raises the hammer to strike the paper). The crossbar seems to both keep the levers from moving too far and provide the force to advance the carriage for the next letter.

So I figured I could use the contact there to complete a circuit. Obviously, each lever and each part of the crossbar that it would contact would have to be electrically insulated. Then I would need something to act as the actual contact. For insulation I used gaffer's tape, which worked admirably. For the contact patches I initially tried aluminum foil but was having a bit of trouble soldering the wire to it. I spoke to my fencing coach, who has plenty of electrical soldering experience. He told me that you simply can't solder to aluminum but offered me a rather interesting bit of material: copper lamé with an electrically conductive adhesive on the back, which I did not even know existed. The stuff is perfect for repairing fencing lamés and seemed to be just what I needed. He got it from a former student who said it was manufactured my a rival electronics comapny and he had never seen it in stores. This leant a certain mystique to the project- working with rare and somewhat mysterious material and so forth.

My first thought was to simply put the wire under the lamé and let the adhesive conduct and hold it in place, but the adhesive wasn't strong enough to keep the wires from moving around. It would have held for a while, but I needed something I could really move around, so I decided it would have to be soldered in place.



After removing the crossbar and covering it with gaffer's tape, I replaced it in the typewriter and used a silver glitter pen (you can tell this was a labour of love) to mark exactly where each hammer touched it. Then I cut triangular strips of lamé and stuck them on over the contact areas. I used alternating triangles so that each one could have some spot large enough to solder the wire in place- the even ones on one side, odd on the other.



Next up were the levers themselves. Oy, what a job. Each lever was wrapped first in gaffer's tape then in lamé. Soldering onto this lamé material works, but the problem is that the stuff is so thin that is burns/melts really easily, so any more than a minute touch of the soldering iron would put a hole in it and I would have to start again.



From here I returned to the crossbar, soldering on wires (this illustration shows only one side done).



Once this was done, it was just a matter of putting it all together. But first: the special keys.

home first steps the special keys putting it together
pictures

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