cotu s.r.o.: 3D printing for small-batch production

The company offers development (design and engineering solutions, technology selection, 3D printing, surface finishing, prototyping) and series production using 3D printing, as well as the sale and distribution of 3D printers, accessories and materials, and the implementation of 3D printing technology in production. It therefore provides a comprehensive service, from product design through prototyping to series production, including finishing operations.

cotu relies on industrial additive manufacturing technologies, primarily using SLA 3D printing (DLP and LCD), i.e. resin printing. It also develops functional eco-photopolymers (resins for 3D printing) and formulates them precisely to meet the requirements of a specific product in terms of strength, flexibility, biocompatibility, etc. These services enable companies to save time and money spent on initial production. If a customer decides to purchase their own 3D printer, they can benefit from the many years of experience of cotu's specialists, who can select the most suitable method for the intended application. They introduce users to proven workflows that they themselves follow in production and are available to provide advice and servicing.

Range of Professional Systems

The portfolio of printers supplied for a wide variety of applications includes brands such as Asiga, Phrozen, Anycubic and rapidshape, both new and refurbished.

The services offered enable companies to save time and money spent on initial production.

Among the most widely used are projector-based Asiga 3D printers. These are fast and reliable DLP printers that enable high-resolution printing using materials from various brands. Thanks to an intelligent sensor system, they achieve consistent accuracy of the printed layers, which is key to producing highly durable prints with a better surface finish than LCD technology. They are therefore suitable for direct production applications without additional surface finishing. Asiga PRO is the first DLP printer with 4K resolution and the largest build area. Thanks to its 385 nm wavelength and sensors, its printing speed is up to 6 times higher than that of monochrome LCD printers. Unlike prints from an LCD printer, the surfaces of these prints no longer require finishing; thanks to their high accuracy, they are suitable for visible applications.

LCD printers in the portfolio are represented primarily by Phrozen products. They were the first to use a monochrome display in their 3D printers, enabling them to print up to five times faster than their competitors. Thanks to the improved ParaLED backlighting system, prints have the same accuracy across the entire build area. One example in this category is the Phrozen Sonic Mega – a large-format LCD printer with 8K resolution, which offers high practical value: a large build volume, high resolution, accuracy and speed. It is an ideal solution for producing a large number of prints at once.

For the production of smaller components, where accuracy and surface quality are particularly important, 3D printers based on curing a liquid photopolymer are the best choice. They use SLA - DLP or SLA - LCD technologies, which differ in the light source used for photopolymerisation.

3D Printing Instead of Injection Moulding Machines

A typical example of where production using 3D printing can be applied is boxes and covers for custom electronics in quantities that do not justify investing in an expensive injection mould.

Compared with using an injection moulding machine, the production process is noticeably faster and simpler. In addition to a high-quality printer and a suitable material, an important stage in production using 3D printing is the preparation and optimisation of the product's initial CAD model. This primarily involves modifying the geometry and optimally designing the required print supports (taking the product's centre of gravity into account). Specialised programs can also calculate an analysis of the likelihood of printing success and adjust the printing process if necessary. At this stage, it is possible to define the production batch and its placement on the build platform, and to divide the model into print layers (known as slicing). Detailed printing parameters are defined in the 3D printer's operating software according to the material used.

Consistent print quality, shape accuracy and dimensional accuracy are crucial to ensuring that everything fits together correctly during assembly. Asiga 3D printers, for example, achieve accuracy as fine as 10 µm. This is achieved through both DLP technology and a system of intelligent sensors and automatic software functions that continuously monitor and regulate printing conditions, such as chamber temperature, light exposure intensity and duration, layer thickness control, edge smoothing, offsets and more. Without these functions, it is essentially impossible to achieve the mechanical durability, layer cohesion and better surface finish of advanced materials, which are more viscous, or to achieve a print success rate of almost 100% rather than 70%. These advanced technologies also make it possible to work with highly durable “unbreakable” materials used in industry, such as BASF ST 45, Loctite 3843 or 3172, which are developed for direct 3D printing of functional parts, particularly in applications where surface detail and strength are important.