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Typo...matic (Part 3)

My Selectric II project is finally 'done'. Here's a demo video.

Please read the previous posts for more details and try to come visit the KC Maker Faire on June 23/24 if you can.

Edit: Here's a great video explaining the Selectric typerwriter(s) mechanisms:

This was my first attempt at serial via straight C code (gcc) in Linux. Needless to say my code is ugly, full of failed attempts to get POSIX serial communication working and bad coding practices. There's a great guide here by the way... I'll get it cleaned up and added (Arduino and C code) to this post as soon as I can but...

The rest of this week and next week I'll be working on a sumobot for the competition at the faire. I'll post about it too...If you've got a mini sumo bot and you're in the area come and compete (mostly for bragging rights) we don't have enough entries yet!


  1. 2 questions (as I happen to have a couple selectric 2's) first, as it is unclear from the video, do the keys depress as if someone invisible was typing on them? I would imagine so since the linkages beneath are pulled and gravity would allow them to fall down (or would if it were not on it's back). Second question, would it be possible to mount one of these with the keys pointed up? Maybe set on a pedestal that would contain the linkages and electronics?

  2. I don't think the keys will drop with gravity, there are feather springs (on the bottom front edge (top edge in my setup)) that would prevent this, so you would have to pull each key down individually (requiring 40 or so solenoids instead of 7) to get the keys to go down...

    It would be possible to mount it with the keys pointed up (so you could type on it and actuate it) I think it can even be done with the type of solenoid I used. The only reason I didn't do it that way was because it is so hard to work on unless flipped up on edge...

    Also depending on how old yours are they may need springs replaced to actually lift up any added weight on the levers...mine did.

  3. This was my favorite thing of all the Maker Faire. Congrats on such an awesome project! I think I have located the victim typewriter, so I'm adding this to my list of projects to have uncompleted on the bench!

    Thank you for sharing, you made Sunday worth coming back for.

  4. Dude. Get yourself a Mag Card Selectric, and learn the transmit block. THis is what you wanted. Faling that, a 5218 printer is a Selectric printer. Similar to the Mag Card.