How are 3D-printed art objects made?
A 3D-printed art object begins as a digital file — a 3D model created in software — and ends as a physical artifact produced layer by layer on a 3D printer. The process involves four stages: digital modelling, slicing, printing, and post-processing. Each stage introduces constraints and opportunities that shape the final object. Understanding this process explains why 3D-printed objects look and feel the way they do — and why features like visible layer lines are a feature, not a defect.
Stage 1: Digital modelling
Every object starts as a 3D mesh — a mathematical description of surfaces in three-dimensional space. At The Bloc Project, models are created using a combination of:
- Parametric CAD software (Fusion 360, Rhino) for precise geometric forms
- Sculpting software (ZBrush, Blender) for organic and corrupted shapes
- Generative scripts (Grasshopper, Processing) for algorithmic geometry
- Deliberate mesh corruption — vertex displacement, boolean errors, and glitch operations applied to clean geometry to introduce intentional imperfection
The choice of modelling approach determines the character of the final object. A parametric model produces clean edges and precise angles. A glitch-corrupted model produces fractured geometry and unpredictable surfaces. Both are valid design strategies; they produce different types of objects.
File format
The standard output format is .STL (stereolithography) or .3MF, which describes the object as a mesh of triangles. Higher triangle counts produce smoother curves but larger files. For sculptural objects, mesh density is typically 200,000 to 2,000,000 triangles.
Stage 2: Slicing
The 3D model cannot be sent directly to a printer. It must first be "sliced" — converted from a solid 3D shape into a sequence of thin horizontal layers that the printer can deposit one at a time.
Slicing software (Cura, PrusaSlicer, Lychee) takes the .STL file and generates machine instructions (G-code for FDM, or image slices for resin). Key parameters set during slicing include:
| Parameter | Typical range | Effect | |-----------|--------------|--------| | Layer height | 0.1mm – 0.3mm | Lower = smoother surfaces, longer print time | | Infill density | 10% – 30% | Internal structure strength; 100% is solid | | Print speed | 40–80 mm/s | Faster = rougher; slower = more precise | | Support structures | Auto or manual | Removable scaffolding for overhangs | | Wall thickness | 1.2mm – 2.0mm | Outer shell strength and surface quality |
For art objects, layer height is a critical aesthetic choice. A 0.1mm layer height produces surfaces that appear nearly smooth. A 0.3mm layer height produces pronounced horizontal ridges that catch light and create texture. Brutalist-influenced objects often use higher layer heights deliberately to make the printing process visible.
Stage 3: Printing
FDM (Fused Deposition Modelling) — for PLA objects
FDM is the most common 3D printing method for sculptural objects at this scale. A thermoplastic filament (typically PLA — Polylactic Acid) is heated to approximately 200°C, extruded through a nozzle, and deposited in layers onto a build plate.
Key characteristics of FDM-printed objects:
- Visible layer lines — horizontal ridges at the layer height interval
- Material colour runs through the entire object — not a surface coating
- Matte, slightly textured finish unless post-processed
- Structural anisotropy — objects are stronger along layers than across them
- Print times for sculptural objects range from 8 to 72 hours depending on size and resolution
PLA is a biodegradable thermoplastic derived from corn starch or sugarcane. It is the most environmentally responsible 3D printing material in common use. However, it softens above 60°C, which means PLA objects should be kept away from sustained direct heat.
Resin (SLA/MSLA) — for high-detail objects
Resin printing uses a UV light source (laser or LCD screen) to selectively cure liquid photopolymer resin, layer by layer. Each layer is typically 0.025mm to 0.05mm thick — 4 to 10 times finer than FDM.
Key characteristics of resin-printed objects:
- Extremely smooth surfaces — layer lines are invisible to the naked eye
- High detail capture — fine textures, sharp edges, intricate geometry
- Requires post-curing under UV light after printing
- More brittle than FDM-printed objects
- Smaller maximum print size than FDM (typically under 20cm in any dimension)
Resin is used at The Bloc Project for objects where surface detail is the primary design consideration — intricate textures, fine geometric patterns, and objects that will be painted or coated.
Stage 4: Post-processing
A 3D-printed object straight off the printer is not finished. Post-processing transforms the raw print into the final artifact:
- Support removal. Printed support structures are cut, snapped, or dissolved away. This often leaves small marks that must be addressed.
- Surface cleaning. For resin: washing in isopropyl alcohol to remove uncured resin. For FDM: removing stringing (fine plastic threads between features).
- Sanding. Optional and selective. Some objects are left with full layer texture intact (the brutalist approach). Others have specific surfaces smoothed for contrast.
- Priming. A spray primer coat provides a uniform base colour and reveals surface imperfections for correction.
- Painting/finishing. Matte, satin, or metallic finishes applied by spray or brush. Some objects receive multi-coat treatments with sanding between coats.
- Quality inspection. Every object is hand-inspected for structural integrity, surface quality, and dimensional accuracy. Objects that do not meet the standard are rejected.
The entire post-processing stage is manual. There is no automation. This is why edition sizes are limited — each object requires 1 to 4 hours of hand finishing work in addition to the print time itself.
Why process marks matter
In mass manufacturing, the goal is to eliminate all evidence of the production process. Injection-moulded plastic is smooth. CNC-machined metal is polished. The consumer should not be able to tell how the object was made.
In brutalist and process-driven design, the opposite applies. Layer lines, sanding patterns, primer ghosting, and material texture are preserved because they communicate something true about the object: it was made by a specific process, at a specific resolution, from a specific material. This honesty is the foundation of the aesthetic.
Further reading
- PLA vs Resin vs Concrete Composite — a comparison of the three primary materials used in sculptural 3D printing.
- What Is Brutalist Design? — the aesthetic framework behind process-visible design.
- Shop all objects — browse the current collection.