Timber › Notes › 3.4 Manufactured boards, veneers and adhesives

3.4 Manufactured boards, veneers and adhesives

Board	How it is made	Properties and uses
Plywood	Rotary-peeled veneers, glued with grain at 90°, odd number of plies, hot pressed	Strong in both directions, stable, does not split near edges; marine/exterior grades use phenolic glue. Cabinets, curved work, boxes
Particleboard	Wood chips + resin, formed into a mat and hot pressed	Cheap, stable, flat; poor edge screw-holding; swells if wet (use HMR). Carcases, benchtops (melamine faced)
MDF	Wood fibres (from refining chips) + resin, hot pressed	Very smooth, machines and paints well, routed edges; heavy, fine dust (wear a respirator). Doors, mouldings, painted furniture
Hardboard	Wet-process fibres pressed with heat, little or no added resin	Thin, dense; drawer bottoms, backs
Blockboard / lamiboard	Core of solid timber strips between veneers	Stiff, lighter; shelving, doors
LVL / glulam / CLT	Veneers or laminations glued with grain mainly parallel (LVL, glulam) or crossed layers (CLT)	Engineered structural members and panels; large spans; mass-timber buildings

Veneer cutting: rotary peeling (continuous sheet, for plywood), flat/crown slicing, quarter slicing (straight striped grain), rift slicing, half-round slicing. Veneers are used for veneering, marquetry (pictures from veneer), parquetry (geometric patterns).
Environmental/WHS issues of boards: use of residues and plantation logs (positive); formaldehyde emissions (choose E0/E1); fine dust when machining MDF; disposal (not easily recycled).
Adhesives: PVA (white glue; ready to use, water soluble, easy clean-up, interior; cross-linking PVA is water resistant), epoxy resin (two-part, waterproof, gap filling, can be tinted as a feature, 2024 Q11), hot melt (fast, temporary/jigs, 2022 MC3), urea-formaldehyde (powder mixed with water; sets by chemical reaction; rigid; interior plywood and laminating, 2023 MC8), resorcinol-formaldehyde (exterior and marine, dark glue line), contact adhesive (both surfaces, bonds on contact; laminates and veneers).