How the Intricate Process of Injection Molding Creates Perfect Lego Bricks

There’s a good chance your brain’s already checked out on this shortened work week. But if you can still muster a thought process or two, you won’t be disappointed by Bill Hammack’s—aka engineerguy’s—latest video which explains the brilliant engineering behind the process of plastic injection molding.

If you take a quick look around your desk, you can probably find countless gadgets and other objects that were made using the process of plastic injection molding—possibly even the computer you’re viewing this on. The manufacturing industry is completely reliant on the process at this point, especially when it comes to toys designed to survive the rigors of playtime.


To mass produce its plastic bricks on an epic scale, Hammack explains how Lego has actually cleverly modified its plastic injection machines to both speed up the process, and produce toys with few of the telltale signs of the molds used. Who would have thought those studded bricks had such an impressive back story? [YouTube]

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The average person has absolutely no idea how much attention is paid to the most mundane details of mass-produced plastic parts. Hours and hours and hours and hours and hours are spent on thinking out, designing, and engineering stuff almost nobody will ever see. If you think gamers and physicists are pale, you should see your average CAD Monkey.