Stacking Block Toy Train (Mk3)

thingiverse

This is a heartfelt tribute rather than a direct reinterpretation of Caj's inspirational [Pull Toy Train](/thing:2133225).\r\n\r\nMy niece has Down Syndrome and is currently working diligently on fine motor control. Her doctors have suggested that stacking toys, such as this one, will significantly aid in her development. So I've been searching for the ideal gift for her upcoming birthday.\r\n\r\nOnce I got my printer perfectly calibrated, I began entertaining the thought of printing a gift, but I couldn't really come up with any good ideas. A few weeks ago, I stumbled upon a Reddit post featuring a customized version of Caj's train, and I thought it would be perfect.\r\n\r\nI immediately printed a set of parts for the "car," but was disappointed in the loose fits and sharp corners. I was hoping to keep this as child-safe as possible by avoiding glue altogether.\r\n\r\n----\r\n\r\nThus was born my "Mark-3" Block Stacking Train. I drew inspiration from Caj, improvements from Anon, and then designed my own system from the ground up.\r\n\r\n* All parts are universal and can be connected in any configuration.\r\n* All parts are printed as single pieces, no glue necessary.\r\n* All parts have a minimum 1 mm chamfer on all edges to avoid sharp corners.\r\n* All thin posts are generously radiused.\r\n* All parts meet the 1.25″ minimum dimension as to not be considered a choking hazard as long as the wheels stay attached to the axles.\r\n* Fits and dimensions are standardized so producing additional or custom blocks is easy.\r\n\r\n----\r\n\r\nParts are broken down into two major categories:\r\n\r\nTwo "Axles," four "Wheels," and one "Car" are assembled into a single train car. The train car forms the base for all stacking.\r\n\r\nAll other parts are "Blocks" and can be printed in whatever quantity you desire. Three included blocks are special as they form the distinctive locomotive shape, but they are also optional.\r\n\r\nA train car can carry 8 "units" of blocks. The "Block-Short" counts as 1 unit, the "Block-Long" and "Block-Square" both count as 2 units--as do all the special blocks: "Block-Cabin," "Block-Boiler," and "Block-Smokestack".\r\n\r\n----\r\n\r\nI encourage you to design your own blocks for this train—I have plans to do so as well. Remixers and block designers should add the tag "[StackBlockTrain](/tag:StackBlockTrain)" to all compatible projects so we can keep them related. The dimensions for blocks are as follows:\r\n\r\n* Blocks are multiples of 15 mm high (square blocks are 30 mm high)\r\n* Blocks are 44 mm wide\r\n* Short blocks are 44 mm long, Long blocks are 90 mm long (1 mm of stacking clearance)\r\n* Post holes are 20.5 mm in diameter.\r\n* A single post hole should be placed in the center of short blocks.\r\n* Two post holes should be centered on long blocks, separated by 45 mm (each hole offset from the center by 22.5 mm).\r\n* All edges should be kept to 45° or less using at least 1mm chamfers when necessary.