Prusa I3 Rework Drop In Replacement/Upgrade Herringbone Gear Set with Solidworks 2014 source

These are drop in replacement Herringbone gears with the same tooth ratio (43:10) as the original spur gear set so you will not need to adjust your e-steps after you swap.
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I never understood why I was seeing herringbone gears that required an entire extruder upgrade to get them to function so I made these.
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After having made this I can tell you there is no way I can feel but the slightest amount of backlash (when I say "slightest" I may actually be over stating it because there