Reduce waste when producing correction braces
“Everything is covered in white dust, which is impossible to eliminate. After a day in production, it is everywhere. You carry it in your hair and clothes. It travels in the air and finds small openings. It is just everywhere. Everybody dislikes it.”
We had scheduled an interview with Ilian Besserlink, who works at Shapemaker. Shapemakers is our Dutch 3D print hub and reseller that guides clients through every process step, whether assisting with design, production outsourcing, in-house manufacturing, or utilizing our software and hardware solutions. So Ilian is the right person to address the subject for the interview, which is about reducing waste in the production of correction braces.
The first topic to come up is the number one pain point: The white dust was a significant motivator for replacing the conventional milling process with the 3D-printed alternative, but let’s take a step back and look at the traditional production of a correction brace.
The conventional process
“Once, one of our customers frankly told us that they pay us to produce and handle waste, and it is not untrue. The torso model is made to form the polypropylene sheets around, and their purpose is achieved when the correction brace is done,” explains Ilian. “But milling torsos is the first step towards a digital workflow. Before, the patient was plastered in gypsum, and the orthopedic technician hand-crafted everything”.
The conventional crafting of a correction brace is a five-step process. At Shapemakers, we mill the torso from the 3D model made from a 3D scan by the orthopedic technician.
Step by step
The process:
- Milling a torso in foam from a 3D model. This creates a positive model.
- Covering the torso with a sheet and/or silicone spray it to resist the heat
- Wrapping the heated polypropylene (PP) plate around the torso and forming it
- Cutting the unneeded parts and fitting it on the patient
- Post-processing and adding straps and coating
Waste is generated at every step of the process.
Milling a torso in foam is pure waste
Rigid foam with a density of 80 or 100 is needed for the torsos. It is sourced in large blocks, which take up significant storage space. A block larger than the model’s dimensions is cut to make it as close to the final dimensions as possible.
The block is placed in the milling machine, and the operator must wear a mask to avoid inhaling the fine dust. The milling machine removes approx 20% of the block and turns it into fine white dust, most of which is sucked by the ventilation system into large bags in a container. However, as described earlier, not all dust is collected. On top of being waste-intensive, the process is unpleasant and requires protective gear.
Ilian has explored a recycling scheme for the foam parts and dust, but it has not been feasible because the waste needs to be pure and collected by the truckload. The need for extra storage to collect enough waste and keep it pure makes it unmanageable.
Preparation of the corset
The foam torso is sent to the orthopedic workshop and prepared with a sheet for heat protection and silicone spray. The PP plate is then heated and formed around the torso. The extra material is removed and added to the waste pile.
The final steps include adding straps and potentially a liner for comfort, followed by fitting the brace to the patient.
Even though the process is partially digitized, manual crafting and heavy waste generation persist. Let’s compare these steps to a fully digital workflow.
Afterward, the torso may need to be stored for a certain period or discarded immediately.
Waste generation in the additive correction brace workflow
Transforming production to a fully digital workflow and replacing subtractive crafting with additive manufacturing improves working conditions and dramatically reduces waste.
It’s a simple story: nearly all waste is eliminated at every step. Waste is generated only in the 3D printing process to support the print. At the same time, material optimization is possible in the design stage, enabling the creation of multi-stiffness zones. This allows a shift from traditional braces with uniform thickness to lightweight versions with rigid zones where correction is needed and flexible zones for enhanced comfort, optimizing material usage.
The machines’ energy consumption is low during production, and the material is clean and dust-free.
Adoption is the challenge
Shapemakers expects to produce more than 1,000 milled torsos this year and is working on transitioning to 3D printing. Waste is a strong motivator for change. Not only is it dusty and requires protective gear, but it’s also expensive to dispose of. The motivation to adopt a fully digital workflow is high.
However, changing traditional treatment practices is challenging. Orthopedic professionals who oversee treatment need to be convinced of the effectiveness of these lightweight braces instead of sticking to the well-known old way of working that they are confident with.
One significant obstacle is that many patients are children. Doctors are understandably cautious about experimenting with treatments for kids, requiring solid proof before transitioning to new methods.
We all need to consider the green transition and make it our responsibility. Reducing waste and using materials suited to recycling contribute to the solution. The maturation of the solution is high at this stage. The material, print strategy, and concept have been evaluated and improved. This has resulted in a high level of documentation and design guides, so it is easy to get started and exploit the full advantages of the technology. To date, it has proven to benefit more than 200 patients.
