Multicolor FDM printing today is a pain: every color change means nozzle purging, a mountain of discarded filament in the “cleaning tower,” and printer time multiplies. The YKG3D project showed a technique that avoids this problem from an unexpected angle — and a Hackaday breakdown within a couple weeks spread across the 3D communities. We open the topic and, at the same time, fill our currently empty 3D printing category.
What’s the problem with classic color printing
Ordinary multi-color systems (AMS at Bambu, MMU at Prusa, ERCF) on every color change perform a tool change: unload one filament, load another, purge the nozzle of the old color. On models with frequent color changes this results in hundreds of changes, tens of grams of waste, and printing several times longer. Hence the famous “cleaning towers” next to the model.
YKG3D idea: don’t swap the tool, alternate colors
The technique (based on research from as far back as 2018) inverts the approach: instead of switching to the required color on demand, the printer systematically rotates the color palette layer by layer. And the manifestation of a particular color at a given spot is controlled by two tricks:
- changing the extrusion volume (how much of that color to push out);
- shifting the layer edge.
Because of this you get smoother gradients and color mixing — and, most importantly, significantly fewer tool changes, meaning less waste and faster printing.
A sober assessment: you pay for everything
This is not a silver bullet, and there are significant limitations — you need to understand them before you get excited about the idea.
- Visible layer height increases. Since colors alternate by layer, the “effective” layer height to the eye increases proportionally to the number of colors: a three-color print with a 0.2 mm layer looks as if a 0.6 mm layer. In other words, color gain comes at the cost of surface roughness.
- Steep walls ruin the illusion. On vertical and steep sections color mixing “blooms” — the technique works better on gentle geometries.
- This is an approach/experiment, not a ready-made slicer plugin on a button. Before expecting perfect results, watch the author’s video and understand where the technique is appropriate and where it isn’t.
In other words, this is not a replacement for AMS/MMU for precise multi-color models, but a clever way to achieve colorfulness where speed and filament savings matter more than perfect surface smoothness.
What to do
- Watch the author’s demo (video) — the technique is much clearer in motion than in words.
- Assess where the technique is suitable: decorative gentle models where speed and economy matter, not micron-level surface smoothness.
- Don’t discard your AMS/MMU: for precise multi-color details with vertical walls, the classic tool change still wins in quality.
- Experiment with the number of colors and layer height: remember the rule “effective layer height × number of colors” — with three colors, choose a thinner layer if surface finish matters.
Sources
- Hackaday breakdown of the technique (July 24, 2026, author Julian Scheffers)
- YKG3D method demonstration video
What color are you printing with — AMS/MMU, manual changes, or single-color models? Willing to live with rough layers for speed and filament savings, or is surface quality more important?