How to 3d print beautiful rainbow filament models？

[Jamesmadison]

I am very interested in colorful 3D printed models. The models in up picture are so beautiful. How to 3D print so perfectly colorful 3d models with rainbow filament?

[Manuel@Raise3D]

For this type of effect, you'll likely see the best results when using a taller model as there would be more color changes the higher you go up. If you have a shorter model, you may only get one or two color changes depending on how short it is.