Graz University of Technology researchers strengthen wood with needle and thread
Graz University of Technology researchers strengthen wood with needle and thread
https://www.eurekalert.org/news-releases/1121389
Publish Date: 2026-03-26 04:24:00
Source Domain: www.eurekalert.org
Wood laminates are used in many different ways, for example in the manufacture of skis and snowboards or in components for vehicle interiors. However, their weight advantages for lightweight construction also have disadvantages. They are significantly less resilient perpendicular to the grain and when force is applied perpendicular to the surface (peeling load), individual layers of wood can easily become detached (delamination). A team led by Florian Feist at the Vehicle Safety Institute at Graz University of Technology (TU Graz), together with the W.E.I.Z. innovation centre and partners from industry, has now developed a method of sewing wood veneers that counteracts delamination in particular. In tests, the stitched veneers withstood four times the force of peeling loads and the fracture energy in peel-mode was fourteen times greater than with unstitched veneer laminates. In addition to applications in vehicle construction and in the sports and leisure industry, it can also be used in the furniture and construction sectors – for example to produce foldable bridge elements or collapsible benches.
Potential adhesive substitute
“Our idea was to reinforce wood where it was really needed,” says Florian Feist. “With targeted sewing, we can supplement adhesives or laminating resins or even replace them in some cases. The principle is based on steel reinforcements (rebars) familiar from civil engineering. Just as the reinforcements in concrete absorb tensile forces, the seams in timber can take up critical forces. This has a particularly positive effect in the event of peeling loads and significantly delays the detachment of the laminate plies.”
The researchers systematically investigated the interaction between wood, yarn, needle geometry and the conditioning of the materials. They had to find needles that would displace the wood fibres rather than cut through them, and a triangular needle tip turned out…
