Review on Wood Trick Mechanical Windmill Constructor by Charles Mathews

This was a great puzzle apart from a design flaw related to the clutch which prevents the blades from turning after the rubber band has been wound up. After a few weeks of thought, I came up with a way to use the old nail as a filling while partially disassembling the device to make the necessary repairs. (Otherwise it would have required quite a bit of disassembly to fix the problem. I should have tested the clutch more thoroughly and adjusted it to my liking before proceeding, so I didn't have to come up with this spontaneous fix.)