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- Change the shafts for the gearbox to a D profile, or look into dogpoint set screws (For this build a D profile is fine)
- Add pocketing to the 1/4 inch plates as well as the alignment blocks in between the plates
- 5 to 1 ratio for pockets is usually the maximum ratio of depth to diameter (if you have a 5 mm pocket, you the minimum diameter tool is 1 mm)
- Be wary of arm vibrations loosening the screws