You need to try it in warm weather with the motor getting hot, as i found with the 3D printed gearbox on the S2 Evo, is that you get heat soak from the motorplate which travels along the gearbox bolts, and softens the plastic which cause's the idler gear shafts to move then strip the gears.
If your using ABS rather than PLA this should be a bit less of a problem as it has a high softening point.
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Jonathan | Atomic-Carbon
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