We are proud to share that our most recent micro injection molding project has allowed us to put our passions for challenges and sustainability in one place by collaborating with innovation and environmental friendly company. However, as nothing good comes easy, this project brought us to a great challenge which will soon be introduced further.
About our client
Since 1825, MyCourant is a rope and rope accessories manufacturer located in France. Courant is a vertical living and safety brand name well-known worldwide. This is a family business where the know-how was accumulated through almost 200 years and was conveyed and developed from generation to generation. The innovation lies deep in the roots of this company and this project is not an exception.
Main Challenges: Design and Sustainability
This time MyCourant team was developing a new “Boule de Ferlette” for recall ropes. It is a ball that is placed in the end of the recall rope for the recovery of false ring fork. This ball is useful during pruning work and can be used even if the rope does not have a splice. In order to have a better picture of how the "Boule de Ferlette" will look like after the process of injection molding, the first 3D printed prototype was created.
However, the initial solution of a wooden anchor with a special surface treatment appeared to have serious drawbacks. The surface treatment was mainly used for better wear resistance and brighter colors, but this made the ball a non-ecological product and too simple in its shape. Basically, it did not represent the company as needed as it had not aligned with one of the main values - sustainability.
“in order to have reasonable costs, we could not do what we wanted in terms of shape since the machining of a product would be complicated but the worse was that it deteriorated quickly, and we had long production times”,
- stated the R&D designer Mr. Laurent Glauser.
The new approach: Biodegradability and Design for Manufacturability
The new design was based on biomimicry and thus, aligns better with the company’s values. Mr. Laurent has worked hardly on a new design to make the product similar to the acorn and manufacturable. Mr. Laurent has previously stated that: “The product should not get stuck through foliage or branches and therefore should be profiled.” The ball had additional design constrains – the strong construction which would be able to withstand at least 200 Kg and ecological materials used, as Mr. Laurent has stated:
“Biodegradability is important since the future is green and ecology is a subject close to our hearts and to our customers”.
Low-Volume Manufacturing: Micro Injection Molding
Right after the new designs were developed, tests were made on ground with professional users and stress tests were conducted with a test bench on 3D printed models. When stress analysis was passed, Mycourant team contacted Micromolds company for the service of injection molding. Since Micromolds company specializes in low-volume manufacturing and micro injection molding, the “Boule de Ferlette” project was a well targeted RFQ. The quote with moldability analysis was sent through 1 business day and the new issue arose: making the design of a ball compatible with injection molding technology.
Challenge No.1 - Undercut Regions
The ball had many undercut regions. This might happen with the new projects and sometimes it is worth to remember, that not everything that is visually attractive can be manufactured. The rope that was winded around the ball had to be shifted to avoid undercuts. Micromolds came up with 3 new design solutions.
Challenge No. 2 - Sink Marks
Since the ball had thick wall regions, there was a considerable risk of material cooling issues which would cause sink marks to achieve better strength. In injection molding, thick walls do not always mean strong walls. Sinking can cause serious problems and can hugely reduce the strength of the part. Engineers and designers had to agree on where exactly and which walls can be thinner as well as what hollowing options were possible to maintain a good appearance of the product.
Challenge No. 3 - Mold Modification
After the first sample check and tests, MyCourant company came up with a complicated modification in mind. When it comes to modification in injection molding, the possibilities are bounded by the exact location and type of the modification in the mold. Since the tooling process is done by the means of material subtraction – CNC machined, this means that the processes cannot be rewinded. In simple terms - the metal chips cannot be glued back to the mold. So, if the modification takes place in the cavity side, enlarging the wall, for example, may be possible because the mold can still be machined. However, if thicker wall is needed in the core side, this might become impossible, since there might be no material left to machine. In this case, modification happened to not be in favor for the Courant company.
Micromolds loves challenges and took risk by trying to do the impossible. It would actually not be possible to put those machined chips back, though machining a little ‘puzzle’ part that could be glued or screwed inside the core side of the mold might seem as a way out. This solution can work in rare cases and is purely dependent on the luck – where the modification takes place. The way around this problem was smooth – the mold was modified and the production was launched.
Results: Final Injection Molded Products and Smooth Collaboration
The cooperation with MyCourant company was smooth and satisfying. Brilliant and fast communication laid a strong foundation for trust between both companies. Altough the project has had many challenges and has taken a long time to be finished, both parties are equally satisfied with the results. Mr. Laurent’s feedback illustrates this nicely:
“We are happy with the result and the quality of the parts obtained, with a biodegradable and compostable material, still young on the market. In addition, Micromolds provided an excellent service and cost-saving advices.”