It is often difficult to achieve good results in rubber processing with 3D printers, the needs of this material may require special technical characteristics and many manufacturers of machines and compounds do not invest enough in research because the industrial rubber market is perceived as not rich enough.
However, there are manufacturers who need to work elastic and resistant polymers, is the case of Assotech, a company specializing in rubber extrusions, silicone and thermoplastic materials, which has chosen 3ntr as the perfect partner to integrate 3D printing in its production line.
With a long tradition that began in 1975 Assotech is today one of the main Italian companies (based in Pianoro, near Bologna) in the production of co-extruded seals in EPDM, PVC and silicone for air and water sealing of all kinds of closures. A niche market that has proved to be an excellent source of suggestions to effectively enrich the offer of solutions for 3D printing of rubber.
For years Assotech has entrusted its production processes to 3D printing, relying on 3d printing bureaus. In 2017 the first meeting with Bologna 3D ( 3ntr partner ) , hence Assotech chooses to rely on 3ntr technology and buys an A4 with 3 extruders, with specific power supply for elastomers, as its first 3D printer, also starting to use proprietary materials such as ABS, Elasto 85 , Elasto 95 and its matching support polymers, thanks to SSI software that allows co-extrusion with different polymers.
“It was not easy to meet our needs with filament-based 3D printing” – Explains Leonardo Benincasa, General Manager Assotech and Head of Production, Quality and Technical Department – “We have invested a lot in research, always supported by 3ntr partner. Without this continuous and constant collaboration made of listening and solutions we would never have been able to face and solve the problems and doubts, we will never have been able to follow new paths and we will certainly not have been able to achieve the excellent quality that allowed us to improve so much our service rendered to the end customer.”
The collaboration between Assotech and 3ntr begins with the need for Assotech to create a first extruded PVC rubber prototype to help a specific customer solve the problem of water and dust infiltration. Generally, such a requirement requires a very complex process, before we get to the resolution of the problem: we start with the design with 3D technical design of the geometry (extruded profile) that should solve the problem posed by the customer.
With the theoretical approval, based only on the design, we move on to the construction of the extrusion matrix through mechanical processing, at this point we begin to extrude a small amount (a few hundred meters) of the PVC rubber profile and then it goes to practical tests, with the doubt that something may not be right and that the whole process is to be redone all over again.
Such a process can take 4 to 6 weeks of work, with an investment of hundreds of thousands of euros.
With the introduction of 3ntr Assotech 3D printers, it reduced the time in 3/5 days of work and a few hundred euros to verify the feasibility, before proceeding with the extrusion matrix.