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Bicycle powered rock tumbler/exerciser Answered

I was wondering if anyone had any ideas for a bicycle powered rock tumbler. Get exercise while watching videos and light tumbling of jewelry or softer stones.


Um, is this the knex forum I posted this in? If so, sorry.
caitlinsdad, Jewelry and softer rocks would not take so long to polish. Plus, whoever was pedalling could do it over a longer period of time. It may make an excellent incentive as well.

I do have put away those tripod mounts which lifts your rear bike wheel off the ground so you can turn it into a stationary exercise bike and a set of freerollers. It should be simple to attach a shaft to drive directly or with a transmission hub/gears to turn the rock tumbler drum. Or let the cylindrical drum ride on top of the wheel and turn.

I'm not sure you could make this out of knex....

Rock tumbling takes hours of well, tumbling to polish the rocks. There have been some drink blenders rigged up for pedal power though.