Specification:
The customer asked for a device capable of washing the surface starch and general debris from the grain. The basic “must haves” were:
100% powered through domestic water supply
No electrical components
Maximum 5kg rice through the system at once
Prototype made with off the shelf parts, and 3D printed parts
Must be wall mounted using traditional fixings
Stage 1 - Concept Visualisation
A number of concept drawings were developed, utilising different systems and mechanisms to effectively clean the grain.
RICE STARCH REMOVAL DEVICE
Stage 2 - Concept Selection and Realization through 3D modelling
Inspired by the simplicity of household salad spinners, design 2 was chosen to develop further.
Basic model drafted
Adaptations made from the original concept, such as:
Moving the water outlet to the top of the container, allowing a tabletop based unit
Discarding the idea of a threaded axle due to overcomplication
Model optimized for 3D printing and print bed size
Alignment with “off the shelf part” availability for the perspex container
Stage 3 - Concept Realization through prototyping and testing
Prototype build commenced
Revisions made to model based off first build performance. Encountered issues were:
Base slots and side slots were too large, resulting in rice escaping through the outlet
Concentricity misalignment caused uneven rotation and part interference
No constraint on the vertical movement of the tray and central axis
Final design confirmed
Slot size reduced
3D printed concentricity jigs developed to ensure proper alignment of rotational parts
Bushing developed to account for axial and concentric misalignment. A part which can easily be replaced with minimal effort.
