This is a fully functional Lego Compound Crossbow. It is around 100 studs long - and combines several techniques that place the Legos under stress to undergo the significant tension of a compound cam with an idler wheel. We used Lego electronics to create the cables, and various wheel elements to distribute the compound pull function with various pulleys.
And of course we wouldn't want to leave ya without letting you see it in action!
So check out the video in the link!
Thanks for reading!
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This was created for our Iron Builder against the Erickson Brothers, and uses the green flexible spike piece as 1:1 scale crossbow bolt tips, viper fangs, a sight window, crosshairs, and trigger.