A well-designed FDM part is strong enough for brackets, clips, hooks and tools around the home. Three things decide how it holds up.
1. Walls matter more than infill
Most strength comes from the outer walls. Adding walls usually helps more than raising infill. For load-bearing parts we use four or more walls and 25–40% infill; decorative pieces need far less.
2. Direction of the layers
Parts are strongest along their layers and weakest across them. We orient hooks, brackets and clips so the load runs along the layers.
3. Heat and sun
| Material | Softens around | Outdoors in Australia? |
|---|---|---|
| PLA | 55–60 °C | Indoors only. Avoid cars and direct summer sun. |
| PETG | About 80 °C | Fine in shade; fades slowly in strong UV. |
| ASA | About 95–100 °C | Our pick for sun, cars and caravans. |
| TPU | Flexible, reasonable heat tolerance | Good for seals and bumpers. |
These are typical figures; exact values vary by brand.
When not to 3D print
We won't print parts where failure could hurt someone: climbing gear, child car-seat parts, structural fixings or anything holding a person's weight.
Common questions
Can 3D prints go in the dishwasher?
PLA will warp. PETG handles a gentle cycle better, but hand washing is safest for any print.
Do prints go brittle over time?
PLA can become more brittle after long UV exposure. ASA and PETG age better outdoors.