Chris Hayes Easy Nylon Part Dyeing Procedure

Markforged Nylon Part Dyeing Procedure

by Christopher Hayes, Special Aerospace Services

Henry Ford is believed to have said, “any customer can have a car painted any color that they want so long as it is black.” Ford eventually offered cars in many more colors once production ramped up.

Markforged is on a similar trajectory – the Mark One is just as revolutionary as the Model T. You can also have parts in any color you like, as long as it’s white, offset by the color of any composites embedded in the part.

There are four color combinations available from the nozzle:

• White: Nylon without any composite reinforcement
• White and Gold: Nylon reinforced by Kevlar®
• White and White: Nylon reinforced by Fiberglass
• White and Black: Nylon reinforced by Carbon Fiber

These color combinations are great for rapid prototypes and mechanically functional parts, but may be limiting for producing finished goods and consumer facing products.

There is an easy solution to this problem, dye.

Nylon’s Material Properties Make It Easy to Dye

Nylon is hygroscopic; nylon will readily absorb water from the atmosphere or direct contact. This is why the Mark One nylon material is stored in the dry box with a humectant.

If your nylon gets wet before you print it will cause some problems. If it gets wet after you print it can create some beneficial changes. Submersion in water will permanently increase flexibility and decrease brittleness and stiffness. Add a water soluble dye and it will also permanently change the part’s color.

We recommend liquid RIT dye due to the low cost, universal availability and consistency of color. It is best to used RIT dye manufactured after 2011 due to a formula update.

For better results dyeing with light colors use additional walls/floor, thicker ceiling and extra dye time. Light colors and thin walls will leave the continuous carbon fiber visible after dying, as shown in the HALO Wallet:

How to Easily Dye Nylon Parts

1. Soak parts in near boiling water for 30-60 min. Use doubled Ziploc bags to prevent leakage. Wear appropriate personal protection equipment, like pot holders, while handling the hot water.

2. Transfer the parts to new inner bag of near boiling water + dye at 5:1 mixture ratio. Fold bag over table edge to remove air and seal inner bag, then agitate the mixture.

3. Fill outer bag with near boiling water and fold over table to seal.

4. Let sit 30-60 min. Agitate occasionally. Reheat in microwave in 30 second intervals and add additional dye if necessary. Do not microwave Carbon Fiber.

SUCCESS – Bright Yellow Key Carabiners

5. Dispose of or save used dye, rinse parts thoroughly and allow 6-12 hours drying time before use. This is especially important for dark dyes; they can leak if firmly squeezed or twisted.

*Carabiner not intended or rated for climbing.