Mesh is made by interlocking fibers, wires, or filaments into an open-grid structure with regularly spaced holes. The exact process depends on the type of mesh: textile mesh is knitted or woven from synthetic fibers, wire mesh is woven on industrial looms from metal wire, expanded metal mesh is cut and stretched from solid sheet metal, and surgical mesh is produced from biocompatible polymers using specialized techniques. Each method creates a distinct pattern of openings that determines the mesh’s strength, flexibility, and purpose.
Woven Wire Mesh
Wire mesh starts as individual metal wires organized into two groups: warp wires that run lengthwise and weft (or shute) wires that run across the width. The process uses an industrial weaving loom, which works on the same basic principle as a textile loom but handles rigid metal wire instead of thread.
The loom holds a set number of warp wires on a beam at the back. Each warp wire is threaded through a heddle frame, then through a tool called a reed, which holds the warp wires at exact, even spacing. Once threading is complete and the assembly is mounted on the loom, a rapier band feeds a single weft wire between alternating sets of warp wires. The heddle frames shift position with each pass, lifting one set of warp wires while lowering the other. The reed then beats the weft wire snugly into place. This cycle repeats automatically, one wire at a time, until the mesh reaches its target length.
Wire diameter, the size of each opening (called the aperture), weave pattern, and overall dimensions can all be customized. Common weave patterns include plain weave, where each wire passes over and under alternating wires, and twill weave, where wires skip over two or more at a time for a diagonal pattern. Setup requires an experienced technician, but once the loom is threaded and calibrated, the weaving runs largely on its own.
Expanded Metal Mesh
Unlike woven mesh, expanded metal mesh doesn’t start with individual wires at all. It begins as a solid sheet or coil of metal. An expanding machine fitted with a patterned blade simultaneously cuts slits into the metal and stretches it apart in a single pass. As the sheet feeds through, the blade creates rows of uniform cuts, and the stretching force opens those cuts into diamond-shaped or other smooth holes.
This pressure-slitting-and-stretching process is one of the most efficient ways to make mesh because it generates very little waste. No material is removed. The sheet simply transforms from solid to open grid. The machine can be programmed or operated manually to control the pattern, and the finished product is either wound into coils or cut into flat sheets. Expanded metal mesh is common in fencing, walkway grating, filters, and architectural panels.
Knitted Textile Mesh
Fabric mesh is typically made through one of two knitting methods: weft knitting or warp knitting. Each produces a different kind of mesh with distinct physical properties.
Weft Knitting
Weft knitting uses a single yarn fed into a circular knitting machine. The yarn interlocks with itself in a repeating stitch pattern, creating a tubular fabric with high flexibility and stretch. Because only one yarn feeds in, the process can produce very thin fabrics at a range of widths. The trade-off is that weft-knit mesh is more prone to runs: if one loop breaks, adjacent stitches can unravel, much like a ladder in a stocking.
Warp Knitting
Warp knitting requires a separate yarn end for each loop across the full width of the fabric. This makes setup more complex but allows each yarn input to follow a different stitching pattern. Manufacturers can mix different fiber types across the width, creating stripes or zones with different stretch, strength, or porosity. The result is more dimensionally stable than weft-knit mesh and far less prone to running. Warp-knit mesh is common in sportswear, industrial filtration, and technical textiles where consistent pore size matters.
Surgical and Medical Mesh
Medical mesh is held to a different standard than industrial or textile mesh. It must be biocompatible, meaning the body can tolerate it without a harmful immune response, and its pore structure directly affects how well surrounding tissue grows into and around it after implantation.
Most surgical mesh is made from synthetic polymers. Polypropylene has been the most widely used material for decades. Polyester mesh, built from multifilament fibers, is hydrophilic, meaning it attracts water and promotes cell adhesion, which helps tissue grow into the mesh and anchor it firmly. PTFE (the same polymer family as nonstick coatings) takes the opposite approach: its chemical inertness and water-repelling surface minimize tissue adhesion, making it useful where surgeons want to prevent the mesh from bonding to organs. An expanded form of PTFE, called ePTFE, introduces a microporous structure that adds mechanical strength while still allowing limited tissue ingrowth for stability.
Beyond these traditional synthetics, biological meshes derived from human or animal tissue support natural tissue regeneration, and hybrid meshes combine synthetic scaffolding with biological components for a balance of structural support and biocompatibility.
3D Printing and Advanced Fabrication
Newer manufacturing methods are changing how medical mesh is built. 3D printing allows engineers to design meshes with custom geometry tailored to a specific patient or repair site. One technique called melt electrowriting (MEW) deposits melted polymer fibers with exceptional precision, controlling fiber diameter and scaffold shape by adjusting temperature, collector speed, nozzle distance, and flow rate. MEW can produce biodegradable meshes from polymers like polycaprolactone that mimic the flexibility and strength of the body’s own soft tissues, then gradually dissolve as natural tissue replaces them. Another fully absorbable material, poly-4-hydroxybutyrate, has shown the ability to support extensive tissue remodeling in animal studies before being absorbed by the body.
How Pore Size Is Measured
Regardless of how mesh is made, pore size is one of its most important properties. In industrial mesh, the aperture is set mechanically by wire spacing or blade pattern and measured directly. In surgical mesh, porosity is harder to pin down because the mesh deforms under tension and pores change shape once implanted.
Researchers use image analysis to quantify two types of porosity. Textile porosity measures the total open space in the mesh as manufactured. Effective porosity focuses specifically on pores large enough to prevent tissue from bridging over the opening without growing through it, which is the measurement that actually predicts how well the mesh integrates with the body. A standardized photographic and software procedure captures high-quality images of the mesh, processes them through a seven-step analysis to sharpen the image quality, then calculates both porosity values. Testing across different operators confirms the results are consistent regardless of who performs the measurement, which is important for comparing products from different manufacturers.
For industrial wire mesh, the relevant measurements are simpler: wire diameter, aperture size, and micron rating (the smallest particle the mesh will block). These are specified during loom setup and verified with physical measurement tools after production.