Let’s Geek Out Over This Retired Lego Mold

Everyone knows Lego is great for making stuff, but how is Lego itself made? With a shiny, super heavy-duty plastic mold like what you see above.

Yesterday the above picture of a Lego mold, retired after producing over 120 million bricks, was posted on Reddit, and it sparked all sorts of geeky questions and discussions, such as…

How long would this mold have been in use before it was retired?

“I estimate that this was retired only after 8 years. I worked in a plastic factory and I assume that this would do 4 cycles a min. Times that by 60 for an hour, times that by 24 for a day (most plastic factories run 24/7 due to the fact that the injectors would fill with hard plastic if left off over night) then times that by about 365 gives you about 134 million bricks. Now I say 8 years cause there is down time for maintenance and colour changes.”

How much money did this one mold produce for the Lego Company?

“At 8 bricks per run, 120,000,000 bricks would take 15,000,000 runs to complete. 120,000,000 bricks at $0.25 per piece would produce $30,000,000 worth of 2×3 Lego bricks. All from one mold.”

What happens to most of these molds once they’re retired?

“They used to bury the old ones in the factory floors. These days they recycle the materials in order to save money. Here is an interesting article…”

Finally, why the hell is Lego so expensive?

“Regular plastic toys like action figures, play sets, etc. are molded with a few very simple criterion: fit, form, function, and appearance. If they don’t have any noticeable major defects and fit together with other mating pieces it doesn’t matter if say an action figure’s arm is .05″ too short.

On the other hand, Legos are a completely different animal. Every single Lego brick made has to fit together perfectly with every other Lego brick EVER MADE. So the piece you get in your new super star destroyer has to snap together perfectly with a piece from a model house made in 1970. To achieve this, they run size tolerances on the order of .0005. That is half of a thousandth of an inch. The amount of process control to get that tolerance on a plastic part is truly incredible.

That’s why Legos are so expensive.”

Some of this talk is just speculation, but still, interesting stuff.

Anywho, if I happen to stumble into a fortune sometime in my life, I’m making it my mission to get my hands on one of these used Lego molds. So cool.

via Wired

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