Manufacturing processes

TEMPERING is the most important stage in the manufacturing process of a cutting tool. It involves heat-treating the steel at a high temperature (approximately 1070ºC or 1960ºF) for a specific period (austenitizing time) and then rapidly cooling it to room temperature. This causes a transformation in the steel’s molecular structure (MARTENSITIC reaction), resulting in increased hardness. Hardness is the physical property necessary to achieve strong, durable cutting performance in the knife. Additionally, the proper internal steel structure provides greater corrosion resistance.

ARCOS performs the TEMPERING heat treatment in continuous furnaces with a controlled atmosphere. Afterward, a second heat treatment called REVENIDO is applied which involves heating the steel to 250ºC or 482ºF to relieve any stresses created by the rapid cooling during TEMPERING. This prevents brittleness and ensures uniform mechanical properties along the entire edge of the tool.

The forging process involves deforming steel that has been previously heated to red-hot temperatures. This is done between two tools called “forging dies,” which have the shape of the desired knife engraved on them. To achieve deformation, high-tonnage presses are used, as a strong force is required to initiate the plastic flow of the steel, allowing it to be shaped according to the engraving on the dies.

An important aspect of this process is that the resulting knife is solid, made from a single piece, thereby avoiding the unwanted welded, glued, or hollow sections characteristic of low-quality knives. These areas are prone to low mechanical strength, breakage, and potential points of oxidation.

Direct injection involves joining the knife tang with the handle plastic to create a solid, robust, and inseparable unit. There are no gaps where water or food particles could enter, making this a completely hygienic process that meets health and safety standards. The plastic is injected in a liquid state (approximately 180ºC or 356ºF) into the mold. The plastic then solidifies around the knife tang, forming a single block that unites the blade and handle.

Double injection is a special process used to form a knife handle, where we use a direct injection machine with two screws. This dual injection system allows us to use two different plastics in the handle. At ARCOS, we have developed three series using this technique: Colour Pro, Dúo, and Línea.

In all three series, we inject POLYPROPYLENE on the inside, a hard material that provides strength and security in the blade-handle union, and RUBBER on the outside, a soft, non-hygroscopic material (does not absorb liquids) that gives the knife a smooth feel and an ergonomic shape, allowing it to fit comfortably in the hand for prolonged use.

NITRUM® is the nitrogen steel formula that is eco-friendly and available exclusively in ARCOS knives. NITRUM® provides greater hardness¹, superior cutting performance², and improved edge durability³. Its new microstructure makes a noticeable difference in knife performance, whether for professional or home use.

The production process of NITRUM® is environmentally responsible. Nitrogen is sourced from the atmosphere, and its enrichment process has no negative impact on air, water, or soil.

High-tech protection for complete bacteriostatic safety in our knives. This involves integrating a sophisticated silver-based technology, Bactiproof Silver®, into the handle to stop the proliferation of bacteria and provide extra hygiene and safety. The system acts as a powerful inhibitor against bacteria, germs, molds, and fungi.

This ensures the knife handle contains the agents needed to protect the plastic from stains, odors, and harmful microorganisms. In short, it is the perfect complement for the kitchen, where hygiene is essential. Bactiproof Silver® reduces the presence of bacteria, fungi, and mold on the handle surface by 99.9%. Furthermore, its antimicrobial performance remains constant throughout the lifetime of the knife.

The sub-zero heat treatment Ice-Plus, applied in the Colour-Pro series, involves cooling the steel to -80°C (-112°F) after the traditional TEMPERING process. This treatment improves the structure of the stainless steel by eliminating the small percentage of residual austenite. The resulting steel structure gives the knife special properties, enhancing both impact resistance and wear resistance.

ARCOS’ commitment to continuous improvement, which has defined the company since its founding, has driven constant product innovation. One of these improvements is the use of stainless steel rivets instead of the aluminum rivets previously used.

These new rivets not only improve handle assembly by providing greater clamping strength, but they also greatly enhance corrosion resistance, ensuring that the knife handles never come loose due to this issue.

The Silk Edge was created by combining the expertise of our master cutlers with the latest innovative technology, resulting in a unique, polished finish along the blade. The process consists of three manual sharpening and polishing stages, producing a smooth and precise cut that impresses anyone who uses it.

Tradition and technology come together to create our special Silk Edge, which was first implemented in the Manhattan series and is now also featured in the Brooklyn, Ópera, and Nórdika series.