Welcome to SAF Lab 101! If you’ve ever been curious about integrating Additive Manufacturing into your production but felt like a caveman trying to use a smartphone, read on.  Whether you’re a complete newbie or someone who’s managed to print a few prototypes and jigs and fixtures, this blog is bursting with tips to turbocharge your knowledge and skills, transforming you from clueless to genius in no time.  Let’s start from the top.

What is SAF?   

Selective Absorption Fusion (SAF™) is a polymer powder bed fusion process that uses industrial-grade printheads to jet high absorption fluid (HAF) onto a powder bed, defining the area in which to form the 3D-printed object or objects. The powder bed is then exposed to infrared (IR) energy to fuse the HAF with the polymer powder. Unlike other 3D printing technologies, this method is economical enough to be used to print several parts at a time for production parts. SAF is particularly well-suited for creating smaller parts, building intricate and highly detailed components quickly and cheaply.

The Fundamentals of SAF Technology

Understanding the basics of SAF technology is crucial for anyone looking to dive into additive manufacturing. Here are the key components and processes involved:

1. Material Selection

SAF technology utilizes materials such as PA11 and PA12, with additional materials like Polypropylene in beta testing. The choice of material is determined by the specific application and desired properties of the final product. Each material offers unique characteristics impacting the printing process, including strength, flexibility, and environmental friendliness.

2. Digital Design

The process begins with creating a digital model of the part using 3D CAD (Computer-Aided Design) software. This digital model is then sliced into layers, which the SAF printer will use as a blueprint for building the object(s). Software is then used to nest the parts logically within the build chamber, utilizing the building files to layout the entire build efficiently.

3. Building the Parts

In SAF printing, a layer of powder material is spread across the build platform in a “Build Box.”  A powder distribution arm evenly spreads the material, and a print head selectively deposits an energy-absorbing fluid onto the powder.  Each layer is then fused together by an infrared lamp, and this process is repeated layer by layer until the entire part is built.  Once complete, the “Build Box” is removed and allowed to cool before extracting the parts and reclaiming the unused powder.

4. Post-Processing

Once the printing is complete, the part undergoes various post-processing steps, such as:

1. Separating the powder from the parts. This is done using a vacuum with a collection chamber. The reclaimed powder is then sifted and the good powder is reused.
2. Removing excess powder from the parts. Even after the parts are vacuumed clean a small amount of the material is usually stuck to the parts.  Using a tumbler or compressed air station is used for manual cleaning.
3. Once the parts are smooth and free of powder, you have several options for finishing them. You can paint, dye, or coat the parts. The natural color of the parts is gray, but some companies choose to change this by applying a different color.

Post-processing is necessary for achieving the desired finish and mechanical properties of the final product.  

Essential Equipment for a SAF Additive Manufacturing Lab

To set up a SAF Additive Manufacturing Lab, you need to equip it with state-of-the-art SAF technology and supporting equipment. Here’s a breakdown of the essential equipment required: