https://youtu.be/9ejWmd5fAZQ https://youtu.be/Yyk3DI67F3Q https://youtu.be/5aau8NodmLg https://youtu.be/vWvYm5YgyDw A little over three years ago I designed, 3D printed and assembled a "horizontally stacked" domino dispensing machine for the kids and grandkids, which they named the "Pink and Green Domino Machine": https://www.youtube.com/watch?v=K12tqdOb0f0 I've have seen a number of variations of the horizontally stacked domino machines over the years, but I have only seen two "vertically stacked" domino machines, so I decided to design, 3D print and assemble this vertically stacked domino machine, which the kids and grandkids have creatively named the "Pink and Green Domino Machine II". When designing a mechanism such as this, I start by isolating the design constraints needed to determine the overall design of the model. In this model, the primary design constraint was the size of a "standard" domino (which I quickly discovered was not that "standard" after all) which would determine the size and swing of the guides, the size and stroke of the piston, the length, width and arc of the track from the vertical stack to the piston, and finally the width and height of the entire model. Along with the domino design constraints, the motor and battery back dimensions must also be considered. After incorporating the various design constraints and dimensions and positioning the various components, the design is completed by "filling in the blanks" required to connect the various dimensions and components with structure and, in this model, gears, control arms and axles. As usual, I probably forgot a file or two or who knows what else, so if you have any questions, please do not hesitate to ask as I do make plenty of mistakes. Designed using Autodesk Fusion 360, sliced using Cura 4.2, and printed in PLA on an Ultimaker 2+ Extended and an Ultimaker 3 Extended.