BigHead’s® TwinDisk®: Efficient fastenings for composite panels and structures

The use of composite panels and structures in the Aero, Auto, Marine, Construction, and other core industries is growing rapidly. These new materials – utilizing carbon fibre, GRP, glassfibre, thermoplastic, wood, and alloy outer skins – are typically bonded to honeycomb, block, foam, or solid core materials.

BigHead® has supplied its unique thin-head fasteners to industry for 40 years. A technical partnership with Caparo Vehicle Products has now provided the composites know-how to perfect an entirely new, high-performance fastener for composite materials. The 316 stainless steel TwinDisk®, with its simple, strong design and unique BigHead® weld technology, provides a rapid and efficient fastening point anywhere in a structure. BigHeads’®own BigBond® adhesives complete the system; for maximum strength, the 2-part FS Acrylic version is recommended for all types of composite materials.

The TwinDisk® has two heads, or disks, joined by an internally-threaded collar or a threaded stud. A hole is drilled into the panel, adhesive applied, and the TwinDisk® is pushed into the cavity. The bottom disk is glued to the bottom skin, and the top disk to the top skin (rebated or surface-mounted). Tensile, shear, and lateral loads are efficiently transferred to both skins. Male versions are supplied with adjustable top heads, fitting depths from 5mm to 100+mm. Threads are M4 to M16 (male or female). Head diameters are 20mm, 30mm, and 40mm; other sizes can be supplied.

EFC International is a leading provider of specialty metal, plastic, electrical and assembled component parts to the OEM and Distribution marketplaces. The company was established in 1983, and has since then set the standard as the sourcing manager for specialty components, technical support, and engineering assistance. EFC is a high-end user of SAP.

EFC International
St. Louis (Corporate) 800-888-3326 fax: 314-434-2902
Chicago 800-727-8466 fax: 630-539-7070
Atlanta 800-541-9019 fax: 770-663-8484

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EFC International is the automation expert in the installation of component parts and fasteners.