Understanding the Challenge
Large Format Additive Manufacturing (LFAM) has revolutionized prototyping and manufacturing by enabling rapid production of parts with minimal material waste. However, when tasked with printing four tall, thin extruder hinge mounts for a client, we encountered significant technical challenges that required creative problem-solving.
These parts were 535 millimeters tall, about 85 millimeters long, and were only a few millimeters thick, and needed to be printed with the longest dimension on the Z axis, which caused some problems.
The Core Problem: Structural Stability
When printing tall, thin parts, the interaction between the printing nozzle and the emerging structure creates a significant challenge. As the nozzle deposits material, it exerts forces on the part that can cause movement and deformation. This movement can lead to two major issues: complete print failure through loss of bed adhesion, or subtle warping in the upper layers that compromises part accuracy. With our requirement to use gray PLA filament, we couldn't simply switch to a more stable material to solve the problem.
Traditional Solutions and Their Limitations
Common approaches to this challenge include repetitive printing attempts or surrounding the part with a protective shell of material. However, these solutions either waste time and materials through failed attempts or require excessive support material that becomes difficult to remove. We needed a more elegant 3D printing design solution that would address both stability and material efficiency.
Developing an Innovative Solution
Instead of viewing the four parts as individual components, we reconceptualized them as walls of a single, more stable structure. By connecting these walls with carefully designed support elements, we could create a unified assembly that would resist deformation while remaining easy to separate after printing.
Implementation Through Precise Design
Using Autodesk Inventor, we developed our solution through these steps:
We imported the .STL files and arranged them side-by-side in an orientation that eliminated overhangs, despite the increased Z-height.
We designed a connecting structure consisting of 45-degree rotated squares, patterned to create a supportive column. They were only two layers thick while the real parts were three.
We exported the entire assembly as a part used for Simplify3D.
Optimization for Manufacturing
The final design incorporated several key features for successful printing:
The support column concentrated mass in the center while using minimal corner connections to the main parts
We added brims to enhance bed adhesion across the entire structure
The geometry allowed for easy post-print separation while maintaining structural integrity during printing
Execution and Results
We processed the design through Simplify3D, the recommended slicer for Compound Dynamics 3D printers, and printed it on our MULE prototype printer. The print required 34 hours and 16 minutes to complete and produced a structure weighing approximately 4.65 pounds. The result demonstrated the success of our approach, delivering four perfectly formed parts without the deformation issues we initially faced.
Conclusion
This case study demonstrates how creative engineering thinking can solve complex manufacturing challenges in large-format 3D printing. By reconceptualizing individual parts as elements of a larger, more stable structure, we developed a solution that maintained print quality while minimizing material usage. This approach not only solved our immediate manufacturing challenge but also established a valuable precedent for future projects involving tall, thin components.
The success of this project highlights the importance of looking beyond conventional solutions when facing manufacturing challenges. Sometimes, the most effective approach involves rethinking the fundamental nature of the problem rather than simply trying to overcome it through brute force methods.
