Bonded fastening meets the digital factory

Click Bond has designed and manufactured more than 4,000 adhesive-bonded fasteners for aerospace, defense, marine, automotive and industrial programs. Source (All Images) | Click Bond

Adhesive bonding has long been hailed as an ideal method for fastening composite structures in aerospace. Unlike traditional drilling and bolting, bonding avoids fiber damage, delamination risks and added weight, resulting in stronger, lighter assemblies that preserve the inherent performance of advanced composites. However, despite the advantages of adhesive bonding, there is a need to dramatically increase production rates. The challenge lies in scalability. Adhesive bonding demands precision in surface cleanliness, application accuracy and cure pressure — all of which can add time, labor and cost. 

As the necessity for increased aerospace production rates grows, with particular regard to commercial airliners and plans for next-generation aircraft programs — all of which will likely incorporate an increasing amount of composite structures, along with the rise of electric vertical takeoff and landing (eVTOL) aircraft — a new wave of automation and digital tools is emerging to bring scalability and repeatability to bonded fastening operations without detracting from reliability.

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Building upon a legacy approach

One of the leaders in this transformation is Click Bond (Carson City, Nev., U.S.), a family-owned company founded in 1987 by pilot and inventor Charlie Hutter. An idea that began as a simple foil patch to fix a leaking rivet on Hutter’s aircraft grew into Click Bond, a global supplier of bonded fasteners and installation systems for aerospace, defense, marine and mobility markets. 

Click Bond fasteners attach to substrates using structural adhesives, eliminating the need to drill into sensitive composites.

The company’s solutions have been used on numerous aircraft programs over the years and have convinced major primes in the industry that adhesive bonding is stronger, lighter and faster. With a portfolio including studs, standoffs, brackets and cable tie mounts, Click Bond designs fasteners to be bonded rather than riveted, supported by patented fixture systems that ensure repeatability and performance comparable to traditional fastened plates — all without the need for drilling.

Click Bond’s focus has always been on removing variability from the process. For each fastener, a disposable fixture ensures the right amount of pressure and the exact amount of adhesive is applied. And, with effective on-site training programs and repair kits, the company has steadily improved installation for techs everywhere and grown the market for adhesive bonding. 

“We’re able to achieve the same performance characteristics as a riveted nutplate, but we’re able to eliminate all the unnecessary holes,” says Bill Perez, senior product application and strategy manager at Click Bond.

The approach is ideal for composite aerostructures because while composites offer lightweight strength and design flexibility, drilling holes for mechanical fasteners can introduce stress concentrations, fiber damage and potential long-term durability concerns. Bonded fasteners address these issues by adhering directly to composite surfaces so there’s no introduction of holes, which puts the entire structure at risk. Done properly, these bonded fasteners are capable of matching or exceeding the strength of drilled fasteners.

However, the process can be time- and labor-intensive. Traditionally, bonded fastener installation has been a manual process. A technician prepares the composite surface by cleaning, abrading and activating it (through the use of plasma, chemical or mechanical treatments to increase surface energy); dispenses mixed adhesive; positions the fastener with a fixture; and holds it under pressure until cure. In order to scale for future demand, Click Bond is investing in automation and digital solutions, developing systems that standardize every stage of the bonding process.

Click Bond’s Digital Solutions use an AR-powered headset to project 3D placement templates onto the airframe.

Automation and extended reality (XR)

“The objective is that every single bond is identical, whether it’s installed on day one or day 1,000, by technician A or technician Z,” Perez states. “Automation allows us to scale bonded fastening with confidence.”

Click Bond is leveraging digital tools to enhance efficiency on the shop floor. One persistent challenge in bonded fastening is locating fasteners accurately on large composite panels, a process that traditionally required using complex jigs and templates — both of which can add time and cost.
The company has introduced a program it calls Digital Solutions, using extended reality (XR) platforms to guide fastener placement digitally. Technicians wearing XR headsets see augmented overlays projected onto the structure, indicating exactly where each fastener should be bonded. The benefits are significant: 

• Faster installation eliminates layout steps and physical templates. 
• Real-time inspection verifies fastener placement within tolerances as tight as 1 millimeter. 
• Digital traceability automatically logs installation records, including who placed each fastener and when.

This innovation addresses key industry challenges such as agility in adapting to design changes, minimizing rework risks, overcoming workforce skill shortages and managing product complexity with enhanced traceability.
The approach also offers intuitive 3D procedures and immersive experiences to transform operations by accelerating product manufacturing development, reducing production risks and converting complex procedures into clear visual steps. It aims to achieve higher first-time quality through process validation. Additionally, it empowers the workforce with rapid learning, engages a digital-first generation and provides quick procedure refreshers for retraining. The solutions further ensures precision and compliance by delivering accurate process information, capturing expert knowledge and enabling digital validation for traceability.

This intuitive process introduces validation and quality control, ensuring greater precision. 

In a pilot program with Vertical Aerospace (Bristol, U.K.), the incorporation of Click Bond XR-guided installation reduced a scheduled 3 weeks for an assembly task to just 5 days, eliminating manual measurements and the creation and placement of cumbersome alignment templates. Vertical Aerospace also incorporated Click Bond XR for adhesive-bonded fastener location and placement, which slashed setup, installation and validation time for thousands of components, cutting weeks of labor and time.

Looking ahead: Innovation and integration

Next-generation single-aisle (NGSA) commercial aircraft programs will require supply chains that allow them to produce as many as 100 aircraft per month — a big step up from the status quo of 58 A320s per month and 40 737s per month. In addition, as advanced air mobility (AAM) aircraft achieve qualification and advance toward commercialization, eVTOL manufacturers are targeting rates closer to those seen in automotive manufacturing than in traditional aerospace. 

By automating surface preparation and adhesive applications, Click Bond automated bonding systems aim to reduce installation time, improve consistency and enhance operator safety.

As composites move deeper into mainstream aerospace structures — from commercial single-aisle wings to eVTOL structures — the need for fastening methods that preserve structural integrity while supporting high-rate production will only grow. 

While Click Bond’s products and guided installation work independently and aren’t required in order to be reliable, its legacy technology is a perfect match for using automation technologies to scale up. The company continues to push the boundaries of bonded fastening through research and partnerships.

One example of the ways Click Bond is continuing to expand its scientific expertise is its recent acquisition of Brighton Science (Cincinnati, Ohio, U.S.), a company specializing in surface intelligence and adhesion-measurement technology. The acquisition aims to enhance Click Bond’s capabilities in delivering scientifically validated bonding solutions, enhancing reliablity and scalablity for a variety of industries.

The company is also exploring new adhesive formulations, advanced robotic platforms and deeper integration of digital workflows. Future systems may incorporate machine vision, AI-driven inspection and closed-loop feedback to further enhance reliability. Additionally, Click Bond is collaborating with standards bodies and OEMs to codify bonded fastening practices, ensuring compliance with aerospace’s rigorous certification requirements.

The company envisions full closed-loop integration, says Perez, where systems not only guide installation but also self-verify adhesive cure, record bond quality metrics and feed data into digital twins of aircraft structures.

“This is the power of full closed-loop integration,” he points out. “We envision complete integration of all of your current processes, your inspection reports, your training, your validation, your verification, and then feed it all back into that digitized set of documents that’s going to carry on with the life of that airframe.”