Selective laser sintering (SLS) 3D printed parts are increasingly relied upon in industries as diverse as aerospace and eyewear design for their superior mechanical properties and cost-efficient production methods. To further improve their aesthetic and mechanical properties, SLS 3D printing users often employ post-processing techniques like dyeing, coating, plating, or painting.
In this guide, we’ll outline the process for dyeing SLS 3D printed parts and review the many benefits this process provides. To learn the full dyeing workflow, download our white paper.
Dyeing SLS 3D Printed Parts: Benefits and Workflow
In this white paper, we will review the considerations, advantages and disadvantages, and available methods for dyeing SLS parts. We will also provide a step-by-step workflow, including preparation techniques and post-dye finishing options.
Why Should You Dye SLS 3D Printed Parts?
SLS 3D printed parts are becoming more common in every phase of the design to manufacturing process. Due to the slightly grainy surface of SLS 3D printed parts, post-processing solutions such as smoothing, coating, and dyeing are growing in popularity as well.
Dyeing is a low-cost method to color SLS parts that enhances their aesthetics while maintaining mechanical properties. Whether one is looking to do a small batch of colored parts or Pantone-match high-throughput production, dyeing methods exist to fit every workflow.
Our team tested four popular dyeing methods and reported on the results. This guide will provide an overview, but to see the full results, download our white paper.
Dyeing can transform a functional prototype, like this bike seat, into a first-generation end-use part ready to send to customers for testing and feedback.
Considerations for Dyeing
Before dyeing your parts, first consider these major factors:
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Price Range/Budget
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Part Size
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Shape
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Quantity
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Color
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Environment of Use
Each dyeing method presents advantages and disadvantages, so it’s important to align your needs with the right solution. The four major methods are pot dyeing, ultrasonic dyeing, pressure dying, and automated dyeing using a machine such as the Dyemansion DM60. Review the chart below to see which method is best suited to your workflow and budget.
| Method | Size | Quantity | Color | UV Stable | Cost |
|---|---|---|---|---|---|
| Pot Dyeing | ★★ | ★★ | ★★ | No | Under 50$ |
| Ultrasonic Dye | ★★★ | ★★★ | ★★★ | No | 100$ to 500$ |
| Pressure Dye | ★★ | ★★ | ★★★★ | No | 100$ to 500$ |
| Dyemansion DM60 | ★★★★★ | ★★★★★ | ★★★★★ | Yes | >50,000$ |
How to Dye SLS 3D Printed Parts
There are various ways to dye SLS 3D printed parts, including affordable methods such as pot dyeing, so it's easy to get started.
Pot dyeing is the most accessible method because it requires only a high-temperature-safe pot and the dye solution, though it provides less consistent results than all other methods, is the most labor-intensive, and sometimes results in damaged parts from heat and stirring. The process is straightforward:
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Mix the solution to achieve the desired color according to manufacturing instructions.
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Heat the dyeing solution until just under boiling.
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Add parts to the pot and stir, keeping the temperature high.
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Once parts appear fully and evenly covered, remove from the solution and leave to dry.
Ultrasonic dyeing provides an improvement over pot dyeing in terms of consistency and maintaining part integrity. This method is less labor intensive than pot dyeing, as the user only needs to set a desired temperature on an ultrasonic cleaner, add the parts, and set a timer. Using ultrasonic vibrations to agitate the solution reduces any chance of part damage during dyeing and provides consistent results.
Pressure dyeing is conducted using a pressure cooker, similar to culinary appliances like the Instant Pot. This method can reach higher temperatures than pot or ultrasonic dyeing. After parts are added to a solution within the pressure cooker, it is sealed and can reach up to 120 ℃. The combination of heat and pressure is conducive to intense color saturating the parts, but a drawback is that the high temperature can also potentially damage the parts — 120 ℃ is above the Vicat softening point of Formlabs TPU 90A Powder.
Industrial systems like the Dyemansion DM60 are cost-effective for high volumes of parts and when extremely consistent results are necessary. These larger format solutions take much of the manual labor out of the dyeing process, and include programmed settings for different types of parts and colors. With a more ‘set it and forget it’ type of system like the DM60, SLS 3D printing customers can spend more time on higher priority tasks, like part design and print optimization.
Dyeing 3D Printed SLS Parts
Users of SLS 3D printers such as the Fuse 1+, will often post process their parts with methods such as coating, electroplating and sanding. In this webinar we will learn more about dyeing as a post processing method for SLS nylon parts.
Getting Started With Dyeing SLS 3D Printed Parts
With affordable workflows such as pot dyeing available, dyeing SLS parts is an easy and accessible way to elevate your parts' aesthetics.
After extensive testing of the four main methods of dyeing SLS parts, the Formlabs team found that industrial solutions imparted the best aesthetic results and reduced labor time. Once past the initial test phase where users decide if color is necessary, they should invest in some type of semi-automated solution such as ultrasonic or pressure dyeing.
The darker base color of Formlabs SLS parts means that only darker dyes are possible, and black is the most consistent, easily achievable solution. For end-use parts or final-stage prototypes, black dye is the best option. To learn more about SLS 3D printing or dyeing SLS 3D printed parts, contact our team. To see the full testing results, download the white paper.
