Go Beyond Concept Modeling: Create Functional Prototypes with MakerBot Tough PLA
| by Josh Snider
UPDATE: MakerBot Tough filament is now available in four colors! With 2X the impact strength of ABS, we used it to explore some new advanced applications—check it out here.More and more companies are investing in desktop 3D printers as their preferred tool for prototyping. And in many cases, they are replacing more expensive industrial 3D printers. Used most often for the early phases of concept modeling, desktop 3D printers allow engineers and designers to accelerate the design process and produce more prototypes at a lower cost. At MakerBot, one of our fundamental goals is to streamline this process and offer solutions that extend what’s possible with a desktop 3D printer. We took a major step in this direction with our newly launched MakerBot Tough filament. It enables designers and engineers to go beyond concept modeling and create durable, high-impact strength prototypes and fixtures. It’s a resilient and strong plastic that mimics or even outperforms many of the mechanical properties of ABS while offering the reliability and quality of PLA.As the graph above shows, under a tensile load, MakerBot Tough filament will deform elastically and return to its original shape before hitting peak strength. Beyond this peak, Tough filament will exhibit a very long plastic deformation range before break that outperforms ABS. In contrast, typical PLA will simply fracture. These mechanical properties make MakerBot Tough filament ideal for prototyping many functional features such as living hinges, snap fits, interlocking parts, and threaded features.
A living hinge is a thin and flexible hinge made from the same material as the two pieces it connects. Since it offers a compact design and can be easily manufactured, it is a great alternative to mechanical hinges. Living hinges are a popular feature in products such as disposable containers and product packaging. Creating living hinges in the prototyping process, however, is not easy. Traditional methods require the use of a second material, such as industrial tape or sheets of polypropylene, which is not only time consuming but also doesn’t accurately represent the final product. Because Tough PLA is designed to deflect and deform before failing, it’s ideal for resilient mechanical features like living hinges. The material has substantial plastic elongation, enabling it to bend into position. It is also durable enough to withstand repeated use, whereas PLA is typically brittle which may cause it to snap.This Tough filament box features a living hinge that can be opened and closed hundreds of times for the entire lifetime of the prototype without breaking. The box can be printed in one part and closely mimics the qualities of a final part produced through manufacturing techniques such as injection molding.
The same qualities that make Tough filament ideal for mechanical features like hinges also make it perfect for features that interlock or snap into place.The Tough filament box features a snap fit that works in concert with its living hinge and tightly secures the lid to the base so that it can be opened and closed for the prototype’s lifetime. Being able to print dynamic, functional prototypes in the office enables engineers to test an expanded range of design features, on demand and at a low cost.
Interlocking parts are a popular feature for products that need to be regularly assembled or disassembled. To make them functional in a prototype, the printing material must withstand both friction and tension. Regular PLA is prone to breaking under force and is therefore not ideal for printing interlocking parts. MakerBot Tough filament, however, is great for printing interlocking parts such as pivots and ball joints. The material is resilient enough to slide and lock into place, then smooth enough to withstand continued use over long periods.This ball and socket joint featured above demonstrates exactly what happens when you try to use a ball and socket joint with PLA and with Tough filament. PLA breaks while Tough filament is flexible enough to resist breaking when the socket is pushed around the ball. It’s smoothness can also resist wear-and-tear from the friction of rotation.
Precise and Durable Threaded Features
In addition to snaps, the properties of MakerBot Tough filament also allow for precise and durable threaded features on prints. Tough filament can be cleanly drilled to create accurately sized holes, and precise threads can be cut into holes using standard tapping tools. This results in durable fastening features that enable parts to be assembled to each other or incorporated into other functional prototypes and assemblies. The resiliency of Tough filament enables sufficient torque to be applied to fasteners and parts to be repeatedly assembled and disassembled.The tapping block example above features drilled and tapped holes that can accommodate fasteners of various sizes. Whereas typical PLA may splinter and shatter under the stress of this drilling and tapping, the lubricious properties of Tough filament enable precise and robust threads. The material reshapes and deforms around the force of a tap creating features that resist stripping or cracking under the stress and torque of a fastener.Whether you’re printing a living hinge, a snap fit, an interlocking part or threaded features, the new MakerBot Tough filament allows you to go beyond concept modeling and create durable, high-impact strength prototypes and fixtures. By adding new materials like Tough filament, MakerBot’s goal is to give professional designers and engineers more ways to iterate faster and more efficiently, empowering them get the most value out of their MakerBot printers.
See more of Tough filament’s mechanical properties in action!