EXBuild Blog

Just as with any manufacturing process, there are optimized and non-optimized ways to design parts for 3D printing. In this case, DFM (Design For Manufacturing) becomes DFAM — Design For Additive Manufacturing — and while your printer won’t chastise you like your machinists will for failing to consider fabrication methods in your design, the part integrity will suffer. This article covers the general outline for printing a composite part on Markforged printers: design, reinforce, print. You might be surprised by how straightforward composite printing is!

Fiber appears in 3D printed parts in two different formats, and it’s important to understand the distinction.

In my classroom I have been using 3D printing for just about 10 years. My district first invested in a 3D printers for our schools knowing that the impact on student learning would be instrumental in their success through college and in their futures. Today, we see a booming industry in additive manufacturing and engineers now are only beginning to see all of the potential applications for these technologies.

How do you decide what material is best for a manufactured part? This simple question has a complicated answer. An engineer must weigh criteria across several domains, including intended function, loading scenarios, work environment, production quantity, available manufacturing processes, and more. 3D printing is appropriate for some production applications, and less so for others. Here, we explore a new process for fabricating end-use parts: 3D printing composite materials.

We often write about the different tools, fixtures, and production parts that so many companies around the world use Markforged technology to fabricate. But it’s not just businesses that benefit from additive manufacturing.

Part Orientation

Whether plastic or composite, FFF or CFF, 3D printed parts are strongest in planes parallel to the print bed — so the print orientation can literally make or break a part. Deposition-based 3D printers build parts in layers of plastic laid down on top of one another. Almost always, the molecular bonds forming the material extrusion itself are stronger than the adhesive bonds of one extrusion of plastic laid on another. Think of the layers like cracks or wood grain - they are slices of material stacked together, so it’s easy to pull those slices apart vertically, or push them past each other in shear.

What Composites Do for 3D Printing

Composite fibers boost specific properties of traditional 3D printed parts - usually strength, stiffness, heat resistance, and durability. This gives them a strength advantage over more traditional thermoplastics used in 3D printing like ABS or PLA, so the applications of 3d printing can expand with these additional materials and the properties they bring to the table.

Before getting to materials and settings that determine the strength of a 3D printed part, it is important to understand the physics and theory driving what aspects of a 3D printed part are important to its strength. In this article, we cover 3 concepts that lay the groundwork for strong 3D printed parts.

At a high level, the 3D printing process includes slicing a CAD file into discrete layers and then building that part layer by layer. In the FFF process, this happens by precisely extruding 3D printing materials in discrete tool paths that trace the outside of a layer and its celled infill.

The specifics of the format of the printer—its construction, what it’s made of, and the quality of its components— factor in to the quality and scale of the parts it can produce.

The Fused Filament Fabrication (FFF) printing process is incredibly adaptable—however, it doesn’t work for every plastic. As a result of the tight constraints required to precisely extrude plastic out of a tiny nozzle, traditional plastics originally optimized for injection molding do not print. The plastics that are printable, however, cover a massive range of compositions, print constraints, and material properties. To find the right material, you need to match the requirements of your applications to the properties of the materials you can print with. In this article, we discuss the strengths and weaknesses of a variety of thermoplastics.