I made this grain bin for my sons play farm. Bin is made of a large tin can for baked beans, with a diameter of 105mm. Legs and braces are 4mm wood craft dowels from the dollar store. Hopper and top are epoxied to tin can, which of course has both ends removed. I cut the tin can down to about 5 inches with tin snips, but it can be as tall as you like. The lid is fastened with a #6 screw. Kind of works with the grain auger i posted previously, (filling is ok, but auger is too big to fit under for emptying. I do plan on making a longer, but thinner auger for these bins, as well as a cross auger for emptying.