Hello folks. I'm a physics major, but have recently become more interested in engineering. I've been playing around with emachineshop and SolidWorks and tinkering with designs, but I am finding that I have a pretty poor working knowledge of basic mechanisms - in particular, I am having trouble mating parts. So my question is: Is there a website, or database, or even a good book where I can browse such devices, preferably with short descriptions, pictures, or schematics? In particular, I am interested in mechanical mating devices like latches, valves, seals, and the like. If anyone could point me in the right direction, I would very much appreciate it! Thanks very much and happy engineering!