We collected our 3D printed mould from the 3D printer. Upon shaking the box with some pipette tips inside, we realised that the mould was not big enough for the pipette tip to fall out of the box through the cylindrical hole at the bottom (i.e. the 3D printer did not print our design as precisely as we hoped it would).
The pipette tips would get stuck in the cylindrical hole at the bottom and be unable to be shot out of the box by an air jet.
Hence, we decided to design a new 3D model with slightly larger dimensions for the cylindrical hole in the box. We also decided to shift the pipette tip mould to the edge of the box so that the pipette tip can be blown out of the box more easily.
Screenshots from the .stl file of our fourth prototype. (Credits: KK)