Test guide · Updated September 2026
Filament transparency tests explained
A filament transparency test shows how the same printed material transmits light at several thicknesses. It helps when planning lamps, lithophanes, indicators, and any part whose colour changes with wall thickness.
Transparent and translucent are not the same
A transparent material allows an image or sharp detail to be seen through it. A translucent material passes light but scatters it, so details blur. Filament sold as clear often prints translucent because boundaries between extrusion lines and layers scatter light. Judge the printed sample made by your machine, not the raw strand or product photograph.
Why printed thickness changes transmission
Each additional layer and extrusion path absorbs or scatters more light. Thin regions can therefore look brighter and less saturated, while thick regions may appear darker or nearly opaque. The generator's windows create one card on which those changes can be viewed side by side.
| Window | Floor thickness | Useful comparison |
|---|---|---|
| 1 | 0.2 mm | Single-layer appearance |
| 2 | 0.4 mm | Very thin walls |
| 3 | 0.6 mm | Increasing colour density |
| 4 | 0.8 mm | Thin functional walls |
| 5 | 1.0 mm | Near-opaque transition |
| 6 | 1.5 mm | Thicker-wall appearance |
How print structure changes the result
Infill and walls
Infill can create visible patterns and extra material behind a test area. Wall count changes the number and direction of extrusion paths through which light travels. Inspect the sliced preview and keep both settings identical across samples.
Pigment and finish
Heavy pigment can make a thin window opaque, while pale or unpigmented material may transmit more light. Matte additives and textured surfaces scatter light differently from glossy surfaces.
Layer direction and settings
Layer height, line direction, extrusion consistency, temperature, cooling, and moisture affect voids and interfaces inside the print. Use the same orientation and the same swatch print settings for every comparison.
Illuminate samples consistently
Use a stable, diffuse light source rather than direct sun, which changes throughout the day. Place the light, card, and viewer at fixed distances. Block unrelated room light when possible. When photographing cards, lock exposure and white balance so the camera does not brighten darker samples automatically.
A repeatable test procedure
- Create a labelled card with the filament transparency test STL generator.
- Slice it flat and record nozzle, layer height, temperature, speed, cooling, walls, and infill.
- Print every comparison card with the same profile and orientation.
- Allow the samples and light source to reach the same room conditions.
- Place each card against the same diffuse light at a marked position.
- Observe the six windows from the same angle and distance.
- Record which thickness gives the useful balance of colour and light for your project.
Generate a transparency test STL
Customize the brand, colour, and material, then inspect the six-window model before printing.
Create a transparency test card