From concept to creation: Understanding custom component solutions

Manufacturing intersects so many industries it can be near impossible to cater exactly to every customers’ needs. Each warehouse can only hold a certain amount of parts and priority is given to those parts common enough to be made in bulk. If a customer requests something specific that a manufacturer doesn’t have the parts to produce, where do they turn to? Custom components. 

Custom component engineering has evolved into a critical value-adding discipline within advanced manufacturing ecosystems. OEMs and Tier 1 suppliers increasingly rely on specialised component partners who can navigate the complex interplay between material science, design tolerances, and long-term performance requirements. Beyond merely addressing application-specific gaps in standard component catalogues, these engineered solutions drive measurable improvements in assembly efficiency, product lifecycle extension, and system-level performance optimisation. 

Of course, producing custom componentry is not an easy or simple process. It requires its own custom tooling machinery and the expertise to design and test a solution that lasts. Longevity is an important consideration in most industries, not least of all automotive. This is where Essentra Components delivers a large portion of its custom components, according to Technical Solutions Manager, Neil Williamson.

“We receive hundreds of projects per year and roughly 50% of them are automotive or [construction and agricultural] which is still in that automotive field,” Williamson says. 

With a background as a mechanical design engineer, Williamson has worked everywhere from the automotive industry to ball point pens. The last 26 years he has worked at Essentra’s design centres, helping with production – designing tooling machines and special purpose assembly machinery. 

While specific solutions have specific applications, the beauty of custom components more broadly is they are used in so many industries. So, while Essentra has many clients in the automotive industry, there is demand across all industries for unique parts to serve a specific purpose. 

Custom Components for Automotive Applications

The automotive sector's evolution toward complex vehicle architectures – from traditional ICE platforms to hybrid and fully electric powertrains – has necessitated sophistication in component design and manufacturing. While many industries can function adequately with catalogue components, automotive OEMs face pressure to optimise weight, performance, and reliability simultaneously, making custom-engineered solutions an operational necessity rather than a luxury afforded by deep pockets.

Williamson explains the requirements of modern automotive projects. 

“Our standard range includes things like caps, plugs, feet, et cetera. Whereas the automotive industry is often looking for more unique pieces like pipe clips, electrical clips, fasteners with more specific applications. They may have an unusual hole size which has a fixing to hold a unique size of cable. A lot of the time our standard range doesn’t meet the requirements for automotive,” he says. 

“Secondly, the automotive industry is very demanding on processing and quality documentation. Once you’ve designed, tested and submitted a part to an automotive customer, they have more than a dozen requirements as part of their production part approval process (PPAP). This proves that Essentra’s parts meet their requirements; that Essentra can produce the right quantity; that it has been measured correctly; that it can be reliably repeated; and meets many other standards.”

The stakes in automotive applications extend far beyond immediate cost concerns. Components that operate reliably within specified tolerance bands directly impact vehicle safety, brand reputation, and regulatory compliance. A single component failure can trigger recalls with costs that quickly escalate into millions or even billions of dollars when multiplied across production volumes. For this reason, automotive design engineers increasingly integrate component suppliers into their development processes during the concept phase rather than treating component selection as a downstream procurement decision. 

Misconceptions of custom componentry

While custom componentry is a well-established process within automotive manufacturing ecosystems, organisations in emerging or adjacent sectors often approach these solutions with limited understanding of their developmental complexities. This knowledge gap frequently manifests in misconceptions that can impede project timelines and create misaligned expectations.

Two critical misconceptions consistently emerge across industry boundaries. First is the underestimation of development timeframes, particularly for miniaturised components where dimensions belie complexity. Though physically small, components requiring precise tolerances within microns must undergo rigorous engineering analysis, material selection protocols, and iterative design validation. Second is the tendency to undervalue the investment required for proper qualification processes. The methodical approach that ensures components perform reliably across their intended operational lifespan represents a significant portion of development resources.

For precision-engineered solutions with specialised performance requirements, organisations should anticipate development cycles extending up to six months from initial specification to production-ready components.

"While standard components have already undergone extensive testing across multiple applications, custom designs require dedicated verification for each specific use case. The investment in this thorough approach ultimately delivers components with significantly higher reliability and application-specific performance, which proves far more cost-effective than addressing performance issues after implementation," Williamson says.

The prototyping process

Regardless of industry, there is a tried and tested process to delivering custom components which Essentra has finessed over the years. This begins with a customer enquiry and a subsequent meeting to deeply understand their vision and application for the part, Williamson explains.

“We receive two types of enquiry. The first is when the customer knows exactly what they want and they’ll send 3D CAD models, 2D drawings, and ask for a quote. In other enquiries, they won’t know what they want but they know what problem they need to solve. In this case, we’ll assess their application and recommend a solution. If the customer is really sure about what they want, we won’t even need to prototype and we’ll go straight to production. However, if there’s any doubt, we’ll always prototype to be sure,” Williamson says. 

Prototyping can take different forms depending on the part and its purpose. The customer’s budget and specifications present another variable, as different demands can warrant more stringent testing techniques. 

"Our prototyping capabilities span multiple technologies, including additive manufacturing through 3D printing and subtractive methods via CNC machining from solid polymer stock. However, the most definitive approach involves creating dedicated prototype tooling for injection moulding. This method enables us to validate performance using production-identical materials and manufacturing processes, providing the best representation of how the final component will perform in application," Williamson explains. 

"While alternative prototyping methods offer valuable insights during early development stages, they inherently introduce variables that can mask potential performance characteristics. The material properties and processing-induced stress patterns simply cannot be replicated with complete accuracy. That's why we consistently advocate for proper prototype tooling for critical applications. We conduct comprehensive testing internally before delivering validation samples to the customer. Once they've confirmed the component meets their specifications, they initiate a production order, which triggers our formal manufacturing implementation process."

The future of custom componentry

The essence of custom component solutions has been largely unchanged for years and will do for many more, but the surrounding technology continues to enhance it. Emerging capabilities in additive manufacturing and biodegradable materials are changing development methodologies and client expectations, as organisations demand components that optimise performance, sustainability metrics, and total lifecycle value simultaneously.

“There’s currently more innovations in speeding things along,” Williamson says. “For example, we can now 3D scan existing parts which customers may supply, rather than drawing them from scratch and customising them that way.”

Essentra currently aims to achieve 50% of raw materials from sustainable sources by 2030 across its polymer range, while its general protection and security seals should achieve 100%. Additionally, the company has completed dozens of trials on different materials at its UK-based Centre of Excellence. This has led to 52 individual product samples and nine individual SKUs. As research progresses, Williamson’s custom solutions team will harness a wider range of materials with which to deliver a range of different results. 

“We’re always excited to see what the Centre of Excellence can produce. After 26 years designing and developing custom parts, I’m passionate about the different and unique solutions we can deliver,” Williamson concludes.