From Bytes to Bones: How We 3D Printed a Life-Sized Human Femur
Can You 3D Print Bones?
After the TAZ Pro Long Bed launched, a great question came up, "Do you think you could print life-sized bones on the Long Bed?" We responded with a resounding, "Yes!" and our team quickly set to finding a fitting model of the human leg ultimately deciding on the 3D printing the longest bones in the body, femurs, at full scale. After printing we compared it to our own legs, only to realize that this femur belonged to a 6’ tall male - taller than most of our staff!
A Lesser-Known 3D File Repository
Any 3D printing enthusiast would be familiar with popular sites such as Thingiverse or MyMiniFactory, but may not know that the government also hosts free file repositories. The National Institutes of Health (NIH 3D) is an excellent example of this, hosting over 13,000 models. You can find diverse projects such as e-NABLE (open-source prosthetic hands for children), COVID PPE, and numerous medical models for use.
Printing Process Details and Notes
While the printing process for this pair of femurs was fairly simple, there were a few important steps that we’d like to go over. Our STL file from the NIH site was the full lower extremity, so we had to isolate the femur using the free software Meshmixer. After importing the file into Cura LE, we laid the model flat and optimized the rotation angle to minimize supports. The bone was then mirrored to 3D print a matching pair.
3D Printed Bones in the Classroom and Beyond
The applications for 3D printed bones extends far beyond just test prints and spooky Halloween decorations. In educational settings, these digital models become invaluable tools, allowing for on-demand printing and custom model creation to accentuate unique lessons. 3D Printing also offers a cost-effective alternative to cadavers and any ethical concerns that may exist. Although Fused Filament Fabrication (FFF) 3D printing may not be commonplace in surgeries, it can play a crucial role in pre-surgical planning. CT scans can be 3D printed to allow surgeons to discuss and strategize a procedure long before the patient enters the operating room.
The Right Tool For the Job
The LulzBot TAZ Pro Long Bed comes standard with a massive Asteroid 285 Tool Head (1.2mm nozzle), great for large layers and high volumetric flow rate, however this project called for a little more finesse. Thanks to the Universal Tool Head system, we were able to swap over to the versatile Meteor 285 Tool Head (0.5mm nozzle) in less than a minute to utilize its finer resolution and steadfast performance for printing the femurs. Balancing between the desired completion time and print resolution is key to any successful 3D printing project. With LulzBot 3D Printers, users can easily outfit their machine for the desired results.
Printer Used : LulzBot TAZ Pro Long Bed
Filament Used : Standard PLA+, Bone White, 2.85mm
STL File - Free Download : Lower Right Extremity_Human Skeleton