3D Printing Basics
Category: 3D Printing & Design — Last updated: July 2025
Fused Deposition Modelling (FDM) is the most common form of consumer 3D printing. A plastic filament is melted through a heated nozzle and deposited layer by layer to build up a physical object from a digital model. It’s the technology I use for all the parts in the shop, and it’s surprisingly accessible if you know the basics.
Common filament materials
| Material | Print temp | Properties | Best for |
|---|---|---|---|
| PLA | 190–220°C | Easy to print, rigid, biodegradable | Decorative parts, prototypes |
| PETG | 220–250°C | Strong, slightly flexible, good layer adhesion | Functional parts, cases |
| ABS | 230–260°C | Heat resistant, can be acetone-smoothed | High-temp environments |
| TPU | 220–240°C | Flexible, rubber-like | Gaskets, grips, shock absorption |
Key settings to understand
- Layer height — thinner layers (0.1–0.15 mm) give better detail; thicker (0.2–0.3 mm) print faster. Most Acorn parts use 0.2 mm as a good balance.
- Infill — the internal structure of a print. 15–20% is fine for most decorative parts; 40%+ for structural ones that take mechanical load.
- Supports — temporary structures printed under overhangs greater than ~45°. Good part design avoids needing them where possible.
- Bed adhesion — a brim or raft prevents warping for large flat prints. Critical for full case shells.
- Print speed — slower speeds generally improve quality and layer adhesion. 40–50 mm/s is a safe all-round starting point.
Printing Acorn computer parts
I print most Acorn computer parts in PETG for its strength and slight flexibility, which helps with snap-fit clips and tight tolerances. Colour matching the original beige/cream plastics is tricky — I keep a small stock of close-match filaments and can discuss specific shades on request.
All parts are designed in CAD with the original machine dimensions in mind. Tolerances are tested on real hardware before any item goes into the shop. Browse the shop for currently available parts, or enquire about a custom commission if you need something specific.
Have a correction or addition? Get in touch via the contact page.