Dave's i3V Universal Spool Axel with dogbone ends

thingiverse

I've created a custom spindle designed to work seamlessly with the I3V kit, allowing me to utilize smaller spools than the standard piece would permit. This bespoke spindle is specifically engineered for use with the stock holder on the I3V, and it's a significant improvement over the wooden one included in the package - you can now easily accommodate all sizes of roll. However, if you're feeling ambitious, consider building an upgraded version that incorporates bearings for even smoother performance.