Dyeing 3D Printed Parts
Plan colour for SLS and MJF nylon parts: base shade, cleaning, surface penetration, batch matching and an approval sample that represents your part.
Choose the base material before the colour
A dye works with the existing substrate. White nylon gives a different colour range from gray or black nylon; the same colour name does not make those starting points equivalent.
| Starting point | Decision | Ask for |
|---|---|---|
| White / natural nylon | Consider for lighter or more vivid shades when the grade is compatible | A sample using the exact powder and surface preparation |
| Gray nylon | Plan around the darker underlying shade | A realistic darker-colour sample, rather than a white-base reference |
| Mass-pigmented black nylon | Decide whether its existing appearance is already acceptable | Texture and sheen requirements; a coating review for a lighter opaque colour |
| Filled nylon, TPU or a specialist grade | Check compatibility individually | Evidence for the grade and the required colour/functional combination |
Browse 3D printing materials and distinguish the powder product from a finish applied after printing.
Surface colour and through-colour are different
Dye changes colour
Dye penetrates accessible polymer surfaces. Base colour, material and cleaning influence the result; a dyed surface is not the same as pigmented bulk material.
Smoothing changes texture
A compatible smoothing process modifies the outer surface. Protect fits and fine details; qualify the final dimensions and function.
Coating adds a layer
Primer and paint add material to exposed surfaces. Specify masking and final fit requirements before coating.
Schematic illustrations; not to scale. Confirm the design for the chosen material, process and final use.
Dye penetrates a material-dependent surface region. DyeMansion lists approximately 0.2 mm on EOS PA 2200 for its DM60 process; that example is not a universal dye depth. A deep scratch or machined face can expose a different underlying colour.
If wear will be visible, identify the contact surfaces and decide whether colour through the material is necessary. Review a mass-pigmented grade, an approved dye treatment or a different finish against that requirement.
For a production drawing, specify the accepted wear appearance rather than treating a dye-depth example as a minimum capability.
Approve the complete surface sequence
Prepare
Clean what the dye will reach
Loose powder and contamination can create uneven results. Check that passages drain and trapped air does not prevent contact with the bath.
Process
Keep the recipe tied to the material
Specify the grade, preceding surface treatment and colour target. Different base powders or smoothing conditions may need a new approval.
Review
Judge the dry, finished sample
Review the agreed colour, sheen and rubbing or wash behaviour in the delivered condition. Record the accepted reference for reorders.
If smoothing is also required, agree the sequence with the processor. See vapor-smoothing selection.
A colour code is the beginning of a specification
| Include | Why it helps |
|---|---|
| Named material, print process and finish sequence | Makes the colour sample reproducible on the intended substrate |
| Colour reference plus approved physical sample | Separates a target colour from the accepted result on textured nylon |
| Visible faces and viewing conditions | Focuses appearance review on the surfaces customers actually see |
| Sunlight, handling and cleaning exposure | Defines relevant fade, transfer or wear evaluation |
| Matching requirements across parts and reorders | Lets the processor review lot control before committing to a match |
Choose another route when dye cannot meet the brief
An opaque coating may be a better candidate for covering a dark base, but introduces its own adhesion, thickness and masking requirements. A mass-coloured powder can help when scratches must reveal the same base colour, yet it still needs texture and service validation.
Frequently asked questions
Can a gray MJF part be dyed white?
A dye is not an opaque white covering over a dark substrate. Review a compatible white base material or an opaque coating if a white finished part is required; confirm the actual process and sample.
Are dyed nylon parts coloured all the way through?
Do not assume that. Penetration depends on the material and dye process. Deep wear, cutting or machining can reveal the original substrate, so request evidence if through-colour is required.
Does specifying RAL or Pantone guarantee an exact match?
It defines a colour target. The base shade, texture, preparation and viewing conditions affect the observed result. Agree an acceptable physical sample and matching criteria before production.
Will dyed parts fade or transfer colour?
They can, depending on the dye, cleaning, washing, sunlight and service conditions. Define the exposure and check the finished sample; a dry visual match does not establish colourfastness.
Sources and further reading
- Formlabs: dyeing SLS nylonTrials on named Fuse nylon powders; base colour, cleaning and exposure affect the result.
- DyeMansion: colour options by base materialColour databases are developed on stated materials and surface treatments.
- DyeMansion: DM60 dyeing specificationsPenetration depth is material dependent; dye is not necessarily through-colour.
Specify the details that make the part work.
Upload your CAD and drawing with the material, quantity, finishing and critical dimensions. Confirm the manufacturing route before production.