How filament painting works
Thin layers of 3D printing filament are partly translucent. Print a dark filament first, then lighter ones on top, and the thickness at each point decides how much of the dark colour shows through – exactly like glazing in painting. A 2 mm relief and 3–4 filament swaps are enough for a photo-realistic portrait or landscape. The technique was made popular by HueForge; this generator does it free in your browser.
How to make a filament painting
- Drop an image above. Portraits, pets, landscapes and line art with strong contrast work best.
- Choose your filaments in order from dark (bottom) to light (top), or click Match image colours. Set each filament's TD (transmission distance) if you know it.
- The swap heights are optimised automatically – the Result view shows the simulated print; compare it with Original and tweak the layers.
- Download the STL plus a text file with the colour swaps, or a 3MF with the colour changes already set for Bambu Studio, PrusaSlicer and OrcaSlicer.
Recommended print settings
| Setting | Value |
|---|---|
| Layer height | 0.08 mm (0.16 mm first layer) |
| Infill | 100 % |
| Orientation | Flat, image facing up |
| Nozzle | 0.4 mm (0.2 mm for tiny prints) |
| Width | 100–200 mm |
| Ironing | Off |
What is TD (transmission distance)?
TD is how thick a filament must be before light no longer passes through it. White and yellow filaments are very translucent (TD 3 mm or more), black is nearly opaque (TD around 0.6 mm). The simulation uses each filament's TD to blend the layers, so the closer your TD values are to your real spools, the closer the print matches the preview. Measure it by printing a 0.08 mm step wedge over black and noting where the black disappears.
Tips for a better result
- Start with black, then add greys and white – a 4-colour greyscale stack already looks great.
- Add one accent colour (for example a skin tone or blue) between the greys for colour images.
- Increase the contrast of the photo before you drop it in.
- Back-light the finished print for a lithophane-like glow.
Frequently asked questions
Is this a free HueForge alternative?
Yes. It covers the core workflow – image to layered STL with colour swaps and a printed-colour preview – free in your browser. HueForge is paid desktop software with more advanced editing; this tool is quick and needs no install.
Which slicers support the 3MF colour changes?
The 3MF includes colour-change data for Bambu Studio, PrusaSlicer and OrcaSlicer. With the STL, add a colour change (M600 / filament change) at each layer listed in the swap file.
Do I need an AMS or multi-material printer?
No. Filament paintings use manual colour swaps on any single-nozzle printer. An AMS just makes the swaps automatic.
How many filaments can I use?
Up to 4 free, up to 8 with Pro.
Is my image uploaded?
No. The image is processed in your browser and never leaves your device.