--- title: "Materials and finishes for coffee machines: a guide to choosing components" description: A guide to selecting materials (brass, stainless steel, aluminium, engineering plastics) and surface treatments for the manufacture of coffee machine components image: https://www.blog.foma.net/hubfs/blog%20foma%20caff%C3%A8.jpg --- [![logo-white](https://www.blog.foma.net/hubfs/logo-white.png)](https://www.foma.net/) - [English](https://www.blog.foma.net/en/materials-and-finishes-for-coffee-machines-a-guide-to-choosing-components) - [Italiano - Italia](https://www.blog.foma.net/materiali-e-trattamenti-per-le-macchine-da-caffè-guida-alla-scelta-dei-componenti) - [GO TO THE SITE](https://www.foma.net/en/) - [CONTACTS](https://www.foma.net/en/contact/) - [English](https://www.blog.foma.net/en/materials-and-finishes-for-coffee-machines-a-guide-to-choosing-components) - [Italiano - Italia](https://www.blog.foma.net/materiali-e-trattamenti-per-le-macchine-da-caffè-guida-alla-scelta-dei-componenti) # Materials and finishes for coffee machines: a guide to choosing components [Foma](https://www.blog.foma.net/en/author/foma) Nov 12, 2026 ---   A good espresso is judged in the cup, but it begins much earlier: with the choice of materials and the precision of the components that make up the machine.  Behind every professional or high-end domestic coffee machine are dozens of metal and plastic components. Some come into contact with hot, pressurized water; others support moving parts; others remain visible and need to look good for years. Each has different requirements, and for each one, choosing the material and surface finish is a design decision—not a minor detail. In this article, we look at coffee machines through the eyes of a component manufacturer: which materials are used, why they are chosen, and which surface treatments make them suitable for an environment that combines water, heat, steam, pressure, and food contact. ## Where components work: the main areas of a coffee machine A coffee machine can be viewed as a set of systems, each with its own operating environment and, therefore, its own material requirements. **Hydraulic circuit.** This is the machine’s hidden heart: fittings, valve bodies, adapters, nipples, and hose barbs. Here, components are constantly in contact with drinking water, often hot and under pressure. Leak-tightness, corrosion resistance, and materials that comply with drinking-water regulations are essential. **Boiler, heat exchangers, and steam system.** High temperatures, continuous thermal cycling, and limescale buildup. Components must retain their shape and sealing performance over time, without deforming or corroding (learn more about machining complex components at [the new FOMA 2 production facility](https://www.blog.foma.net/en/new-production-plant-foma-2?hsLang=en)). **Brew group and portafilter.** This is where water and coffee meet. Surfaces come into direct contact with the beverage, are cleaned frequently, and undergo mechanical stress every time the portafilter is locked into place. **Coffee grinder.** Shafts, bushings, locating seats, and burr supports operate in rotation for hours. Dimensional stability is crucial here: grind consistency also depends on how well the supporting components maintain alignment. **Decorative components and controls.** Steam wands, knobs, taps, trim, and exposed finishes. In addition to performing their function, these parts must convey the quality of the brand and withstand handling, cleaning products, and steam. ## Materials for coffee machines: five families and their roles There is no single best material. There is the right material for the function, operating environment, and target market of the machine. 1\. Conventional brass (CW614N and CW617N)   Brass has long been the go-to material for hydraulic components and many visible parts. It is easy to machine, enables tight tolerances with short cycle times, conducts heat well, and provides an excellent base for electroplated finishes such as nickel and chrome plating. Alloys such as CW614N and CW617N remain widely used where components do not come into contact with drinking water. 2\. Low-lead brass (CW510L and CW724R) Lead, historically added to improve machinability, is now under scrutiny in European and international regulations governing materials that come into contact with drinking water and food. As a result, coffee machine manufacturers are moving toward low-lead or lead-free alloys, such as CW510L or silicon-containing alloys such as CW724R. These retain the typical qualities of brass but require different machining parameters, cutting tools, and chip management. Machining them effectively calls for specific expertise—not simply a change of bar stock. 3\. Stainless steel (AISI 303, 304, and 316)   AISI 303, 304, and 316 stainless steels are a natural choice for structural components, parts in direct contact with the beverage, and anything that needs to withstand corrosion, cleaning products, and thermal cycling. Grade 303 offers the best machinability, while 304 and 316 provide greater corrosion resistance, which is useful in the presence of steam and hard water. In coffee grinders, stainless steel shafts and bushings ensure dimensional stability even after hours of continuous operation.   4\. Aluminum (EN AW-6082 and 6061) Alloys such as EN AW-6082 and 6061 are used where weight matters and temperatures remain moderate: supports, housings, grinder bodies, and decorative components. Aluminum combines good rigidity, high machinability, and an attractive appearance after surface finishing. 5\. Engineering plastics (POM, PTFE, and PEEK) Not everything in a coffee machine is metal. Certain machined engineering plastics solve problems that metals cannot, and often work alongside them: - **POM (acetal resin):** low friction and good dimensional stability, making it ideal for bushings, guides, and small mechanical components. - **PTFE:** chemically inert and nonstick, suitable for gaskets, seats, and sealing rings. - **PEEK:** withstands high temperatures while retaining its mechanical properties, making it suitable for components near the boiler and brew group, where other plastics would fail. | Material | Applications | Key strengths | | --- | --- | --- | | Brass | Fittings and visible components not in contact with drinking water | Machinability; excellent base for electroplated finishes | | Low-lead brass | Hydraulic circuits, fittings, and valve bodies | Drinking-water compliance; the performance of brass | | Stainless steel | Brew groups, shafts, bushings, and parts in contact with the beverage | Corrosion resistance; dimensional stability | | Aluminum | Supports, housings, and decorative components | Low weight; rigidity; attractive appearance | | POM, PTFE, PEEK | Bushings, guides, seals, and insulating components | Low friction; chemical inertness; heat resistance |   ## Surface treatments for components: nickel plating, chrome plating, and TEA Plus The material defines the core performance; the surface treatment completes it. In a coffee machine, the surface is what comes into contact with water, steam, limescale, cleaning products, and hands. This is where much of the product’s durability and appearance is determined. **Nickel plating** creates a uniform layer that protects brass against corrosion and oxidation and increases wear resistance. It also provides an ideal base for subsequent chrome plating. It is used on both internal components and visible parts. **Chrome plating** is the bright finish associated with quality coffee machines: steam wands, taps, trim, and knobs. Beyond its appearance, it provides a hard surface that is easy to clean and resistant to scratches and the cleaning products used daily in cafés. **TEA Plus** is an environmentally friendly tin-nickel alloy electroplated finish, developed as an alternative to conventional nickel and nickel-chrome coatings for components in contact with drinking water or food. Applied to brass and copper alloys, it reduces the release of nickel and lead into water and offers good corrosion resistance with a semi-bright appearance. It is included on the 4MS positive list of materials suitable for contact with drinking water, is approved to NSF/ANSI 51, and meets EN 16889, the standard specifically addressing professional coffee machines. The surface treatment should be chosen alongside the material, not afterward. The same brass component may require a different finish depending on whether it comes into contact with water, is exposed to steam, or is simply visible. Each treatment must also be compatible with the compliance requirements of the target market. ## How to choose the right materials and treatments: four questions for the design stage When designing a new machine or updating an existing assembly, a few key questions can help guide the process. 1. **Does the component come into contact with drinking water or the beverage?** If so, the choice immediately narrows to compliant materials and treatments, such as low-lead brass, stainless steel, or food-contact-grade engineering plastics, in accordance with Regulation (EC) No 1935/2004 and individual market requirements. 2. **What temperatures and stresses will it operate under?** Components near the boiler and brew group need materials that remain stable when exposed to heat. Where parts rotate, wear and friction are key considerations. 3. **Will it be visible?** If the component contributes to the machine’s appearance, the surface finish becomes part of the design and should be defined from the outset. 4. **What are the production volumes and expected product life cycle?** Machinability and material cost carry different weight in a pilot batch compared with series production that will continue for years. Answering these questions together with the supplier, before the design is finalized, helps avoid rework, certification delays, and hidden costs.   ## FOMA: custom-manufactured components for coffee machines At FOMA, we manufacture components to customer drawings using all the material families described in this article: conventional and low-lead brass, stainless steel, aluminum, and engineering plastics such as POM, PTFE, and PEEK. Through our network of qualified suppliers, we complete components with nickel plating, chrome plating, and TEA Plus, delivering them ready for assembly. For coffee machine manufacturers, this means a single point of contact for a wide range of components: from hydraulic circuit fittings to grinder shafts, and from engineering plastic bushings to decorative chrome finishes. Our approach starts with the drawing. Before production begins, we work with the customer to review the material, tolerances, surface treatment, and regulatory requirements of the target market. We manufacture parts using CNC and multi-spindle lathes ([discover the advantages of series production on multi-spindle lathes](https://www.blog.foma.net/en/multi-spindle-high-volume-machining?hsLang=en)), in batches ranging from a few thousand to millions of parts, with statistical process control and traceable documentation for every order. Our experience with customers in the valve, fittings, and automotive industries translates into a structured, verifiable approach to quality. ### Sign up for our newsletter to stay updated and receive insights and information on the sector! [![logo-white](https://www.blog.foma.net/hubfs/logo-white.png)](https://www.foma.net/) For years Foma has been synonymous with quality and efficiency in the field of mechanical processing and a leading company in the production of small metal parts. ### CONTACTS - [T. +39 0322 999094](tel:+390322999094) - [F. +39 0322 999907](tel:+390322999907) - [mail@foma.net](mailto:mail@foma.net) - [www.foma.net](https://www.foma.net/it/contatti/) ### LOCATION - [Via M.te Cerei, 45/46 Quare 28011 - ARMENO (NO)](https://goo.gl/maps/PS1NK4vD9jHtxrJSA) ### MENU - [Go to the site](https://www.foma.net/en/) 2026 © Foma Srl - P. IVA 00612500033  [Privacy Policy](https://foma.net/en/privacy-policy/)