Animagraffs
If you learn best by seeing every part in its place, this is the channel. Jake O'Neal rebuilds a whole machine or structure in 3D, then cuts it open and runs it: how the Golden Gate Bridge works, how Hoover Dam works, how a diesel-electric locomotive, a helicopter or a manual transmission and clutch works.
There is little math, but the models are researched closely enough that he makes separate videos about how he recreated them. That makes it ideal for younger viewers and visual learners, and a fine first look at a machine before you read about it in depth.
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