Tumbler test

Because i did'nt found any relevent informations about how rotary tumblers work on PLA, i decided to build one my self .
!!! This is a WIP !!! .
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Part list:
- Nema 17
- 3 X 608zz
- Arduino
- Easy Driver Stepper driver
- Gear set => thing:10707
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If some are interested i'll keep updating about results:
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First test (running atm) :
- sand + wood screws (sand not totally dry)