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Defy Design · Botany, NSW

Industrial recycling in Australia

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At Defy Design, I worked across an industrial recycled-plastic production line and led mechanical improvements to the upper wash basin, filtration, structure, drive system, material handling, and floor equipment. Hover or click a process stage to see how it works and what I built.

Redesign material handling for forklift access and fewer manual steps. Enable the washline to process mixed-density feedstock, including shredded syringes. Improve the air-transport system that moves flake between machines. Build real DFM and DFA intuition through hands-on fabrication.
AssembliesAutoCADDesign for Manufacture (DFM)Fluid MechanicsGD&TMechanismsPlastics ManufacturingRoot Cause AnalysisSolidWorksStructuresSustainabilityManufacturing Processes
Mechanical Engineering intern
Feb 2026 - Jun 2026
Built a scissor-lift trolley from recycled sheet that removed manual handling of 100 kg molded parts between the oven and compressor. Designed 400 mm lift blocks that raise a one-ton hopper into forklift reach. Designed the upper wash basin, its passive spiral filter, and the rotating discharge valve, covering wall stress, bearing preload, friction torque, gearing, and motor selection. Iterated pelletizer blade geometry through 3D-printed prototypes. Applied DFM and DFA across production fabrication on a live recycling line.
Fig. 01 · Factory line, Defy Design
01
Shredding
02
Washing
03
Air transport
04
Sheet extrusion
05
CNC routing
06
Floor assembly
Pellet branch
3a
Pelletizing
3b
Injection molding
01Waste in, flake out

Shredding

The process

Post industrial and post consumer plastic gets granulated into flakes. Sorting by polymer and colour happens before this step, because contamination here ruins everything downstream. Offcuts from later stages loop straight back into this hopper.

Station 01
Shredding
Waste in, flake out
What I designed and built

When the hopper bags needed to be taken from the initial hopper to the auger, staff would have to awkwardly angle the forklift under the stand as the bottom of the hopper went below the lip of the bag. Using offcuts from the main production line, I designed 400mm lift blocks to carry the 1 ton load and prevent side-side oscillation.

The main feed hopper the lift needed to support.
The main feed hopper the lift needed to support.
Three offcut panels fastened together, raising the hopper 400mm under a full ton of load.
Three offcut panels fastened together, raising the hopper 400mm under a full ton of load.