Hey, this is a creation of Henry Segerman. He made a very interesting Video about this Mechanism. I made this version for myself and thought it would be a shame not to publish it. I got his approval. This is published under a non-commercial license, so you cannot sell this.
You need: You can theoretically make this as long as you want, but if you want to have the configuration on the picture you need: 6x linked Gear 6x Gear 11x Connectors I made an "All" File that has all of those in one file.
Print Settings: Standard. No supports.
Assembly: I made a picture Series that you can view above. Here are the steps. First push connectors in the holes of the gears as shown. You should have 6 Gears with Connectors at the end. Push another connector in one of the holes of a linked Gear. You can now push another linked gear on top to connect both. Now build a chain out of all linked gears this way. Straighten the Chain so that the Tooth of the Linked Gears overlap. Now you can push the Gears in between the linked gears at the top and the bottom. Make sure that your Chain remains straight through this, and otherwise it will hinder the functionality. Done. You should end up with the Chain shown in the picture and it should be able to move.
Published under https://creativecommons.org/licenses/by-nc-sa/4.0/