Garden Concrete Molds

Design Considerations

Low fabrication cost
Manageable component weight
Long-term durability
Weather & moisture resistance
Reusable mold construction
Resistance to curing heat

Design Solution

I developed a reusable 3D-printed mold system for producing individual concrete components that interlock to form a continuous garden wall.

The interlocking geometry is intended to minimize gaps between components, preventing soil from escaping while maintaining a Victorian-inspired appearance.

The design also emphasizes affordable fabrication, repeatable casting, and straightforward demolding, allowing individual wall components to be produced without requiring a different mold for each piece.

First Iteration: Initial Concept and Material Selection

My initial approach focused on replacing the deteriorating garden boxes with a modular concrete wall system. I selected concrete for its potential durability, weather resistance, and ability to form decorative components suitable for outdoor use.

I then developed 3D-printed mold geometries intended to produce individual pieces that could connect into a continuous structure. The challenge was to balance the desired appearance and interlocking features with a mold design that could be manufactured affordably and allow the cured concrete to be removed.

Second Iteration: Geometry and Material Refinement

The initial mold design revealed a significant manufacturing challenge: heat generated by the exothermic reaction during concrete curing caused the PLA molds to warp, affecting their ability to maintain the intended geometry.

To address this, I transitioned from PLA to PETG (Polyethylene Terephthalate Glycol) for improved heat resistance. I also softened the internal angles of the mold to facilitate concrete removal and reduce the likelihood of damaging the cast components during demolding.

These changes were intended to improve the mold's thermal resilience and manufacturability while preserving the geometry required for the interlocking concrete wall.