In many assembly applications, screws, bolts, and other conventional mechanical fasteners have given way to flexible fastening materials. There are many reasons for the switch, including reduced product weight and cost, improved appearance, and reduced assembly time by making it unnecessary to precisely fit individual components together. In automotive, industrial and consumer applications, flexible fasteners eliminate problems caused by vibration, which can loosen mechanical fasteners and cause noise and possibly detachment of components. In outdoor applications, the materials offer excellent UV resistance and will not rust like metal fasteners.

Sometimes suppliers of these flexible fastening materials produce additional value for customers by partnering with converters to provide custom assembly solutions for moderate- and high-performance applications. Working with the material supplier, converters can identify the best fastening material for a customer from among the supplier’s offerings. Converters with an in-house engineering staff also provide other design-related assistance to improve both the product itself and the manufacturing process.

Once design work is completed, converters turn the chosen fastening material into the appropriate form using a variety of machines and processes. These allow the firms to handle all types of converting jobs, as well as related tasks such as welding and even sewing.

Flexible Fastening Options

Scotchmate Reclosable Fasteners.

3M manufactures several different flexible fastening products. These include “reclosable” fasteners, which produce a secure attachment but can also be opened and closed many times. These fasteners eliminate holes, snap caps, fastener heads and protrusions, resulting in clean lines and sleek profiles in many applications.

One widely used reclosable fastener is the 3M^TM Scotchmate Reclosable Fastener, which features stiff hooks that mesh with pliable loops to allow fast and easy closure in applications that require repeated openings and closings. Available in different strengths, thicknesses and colors, they offer a tailored appearance for frequently removed parts of indoor and outdoor structures, such as displays, exhibit booths, offices, and automotive interiors. Other common applications include aircraft seat assembly and liner pads inside sports helmets.

Standard hook-and-loop fastening materials are easily removed and replaced, but they tend to lose their holding ability over time and when exposed to vibration, especially when the applications involve high weight or large fastening areas.

For more demanding fastening and assembly applications, 3M^TM Dual Lock Reclosable Fasteners are available. These industrial-quality fasteners feature small, interlocking mushroom-shaped stems with five times more tensile strength than standard hook-and-loop fasteners. An alternative to zippers, screws, snaps, hooks and bolts, these fasteners offer design flexibility, fast product assembly, smooth and clean exterior surfaces, and improved product performance in many applications.

Dual Lock Reclosable Fasteners can be used in electronic, electrical, aerospace, automotive and marine applications. The material replaces screws in wall and ceiling panels in many transportation applications, eliminating drilling, screwing, and corrosion. In addition, Dual Lock Reclosable Fasteners help produce clean product design and allow components to be quickly removed for servicing or circuitry upgrades in electronic components and cabinetry assembies.

Unlike reclosable fasteners, 3M^TM VHB^TM Tape doesn't allow repeated opening and closing. It can, however, replace screws, rivets and spot welds in permanent high-strength bonding applications. Offering the convenience of a tape with the strength of mechanical assembly options, the acrylic tapes bond to metals, plastics and glass, eliminating drilling and unsightly fasteners. The foam conforms to many irregular surfaces and helps provide sealing, cushioning, and impact resistance.

The tapes are used in the construction, transportation and electronics markets. In electronics applications, they provide reliable and durable component attachment, as well as temperature resistance, shock and vibration reduction, and sealing to keep out dirt and water. In the transportation industry, the tapes replace mechanical fasteners used in side-panel attachment to give vehicles a clean, smooth appearance, while also delivering the strength and durability necessary to meet vehicle requirements.

The Converter's Role

To obtain flexible fasteners that meet their specific requirements, manufacturers should work with a converter that has a working partnership with a material supplier. 3M collaborates with Fabrico, a leading provider of design and manufacturing services for flexible materials. Top converters like Fabrico have experienced design-engineering teams that can help customers choose the best material for a fastening application. If a customer starts out by selecting a high-cost material, for example, the converter, working with specialists from the material supplier, may be able to identify a less-expensive material that meets application requirements. A supplier with a large selection of products like 3M might be able to provide a material that both costs less and performs better than the customer’s original choice.

Converters can also help customers turn fastening concepts into finished designs. Some converters can handle rapid prototyping tasks using 2-D and 3-D CAD solid-modeling software and tool-less sample-making equipment. A converter’s engineering staff can also make suggestions for improving customer designs. For example, sometimes customers come up with designs that aren’t readily manufacturable. With their knowledge of materials and manufacturing processes, converters quickly spot such problems and recommend redesigns or modifications that make the components easier to manufacture, which reduces production costs and time while retaining the functionality that the customer needs.

Manufacturing Capabilities

When a design is ready for production, converters turn flexible fastening materials into rolls, pre-fabricated parts and custom fabrications. There are a variety of custom size and shape requirements, which frequently require that intricate patterns be cut to tight tolerances with high-performance die-cutting equipment, and that materials be laminated with either pressure-sensitive or non-pressure-sensitive adhesives.

Many types of equipment and capabilities allow converters to tackle difficult fastening materials. For example, Fabrico’s high-performance water jet cutter allows accurate cutting or slitting of difficult-to-die-cut products without damaging the material or the blades of conventional cutting machines. In addition, the firm can handle custom converting of thick foam materials, such as 3M VHB Tape, which is hard to convert because it tends to re-bond to itself after being cut.

In addition to converting machines, specialized in-house equipment is sometimes required. Fabrico uses an ultrasonic welder to spot weld two die-cut strips of Scotchmate Reclosable Fasteners or Dual Lock Reclosable Fasteners to produce long straps of the materials, which are wrapped around bundles of cable and tubing. A permanent bonding method that doesn’t require costly adhesives, welding melts the two strips together to form a homogeneous structure that retains the strength of the original material.

Conclusion

Manufacturers interested in switching from hard to flexible fasteners may be best served by partnerships between top converters and flexible-material suppliers. For customers, the benefits of such partnerships include a variety of material options and expert assistance in selecting the right material for a particular fastening application. The converting partners also offer other types of valuable design help, as well as a range of manufacturing capabilities that turn designs into effective flexible fastening solutions for applications in many industries.

For more information, www.fabrico.com/3M.