Making a wheel for a toy tricycle Have you ever tried to insert a crank into a wheel for a toy tricycle? This is one idea I have developed to enable me to do just that. This is an experiment for an idea I have for making a crank for a tricycle wheel. I used a plastic pen as the axle, wire for the crank, and MDF for the wheel.  I made these Sketchup models to try to explain the process. I find it’s not easy for me to explain the things I do, so bear with me here. First drill the holes in the plastic sleeve using a wood dowel plug as support. The holes are shown as the white cylinders in the illustration. I have also let it stick out a bit on both ends to enhance the supporting function.  A photo of the plastic sleeve with the hole. The red part is the notch cut away. The dowel is cut to fit as shown.  The white cylinder represents one of the two holes I have drilled along the length of the dowel. Only one crank is shown for clarity. The complete assembly.  For m...