Sturdy construction of drawers is very important due to the rough and jarring ride that will occur off-road and the heavy loads that may be carried. Most cargo drawers for 4WDs are constructed from materials that are tough, relatively inexpensive and preferably light in weight. The list below explains the advantages of the various materials used by manufacturers in constructing cargo drawers. Each manufacturer will have their own preferred material. Shop around to choose the system that best suits your needs and budget.
The main advantage of using galvanised steel is: it’s not expensive, easy to work with, commonly found and it comes in a large variety of shapes and forms. Galvanised sheets usually come in 0.9mm, 1.2mm and 1.6mm and can be easily bent into box shapes or channels using a pan brake or a hydra bend machine. Strengtheners may also be used such as: “U” channel and “top hat”. Galvanised steel is usually used in the framework of the cargo drawers, either spot or MIG welded (much stronger) or bolted with nylock nuts.
Aluminium is quite light and relatively soft when compared to galvanised steel; however, it’s much more expensive. Aluminium can be very strong when it’s used with strong framing concepts and utilising strengtheners such as: rectangle hollow, “top hat” or “T” bar. Some manufacturers are utilizing both extruded and folded aluminium, which provides great strength (around 120kg per drawer), without weighing in as excess baggage. Storage drawers purely constructed in aluminium can result in up to 60% reduction in weight when compared to other materials on the market. This will obviously provide lighter overall vehicle weight and thus lead to better fuel economy.
Plywood was the very first type of engineered wood and it is made up of a number of layers of veneer, each layer glued at right angles to the adjacent layers. These layers are bonded under heat and pressure with strong adhesives such as phenol formaldehyde resin. Plywood is known to resist cracking, shrinkage, twisting or warping and it is generally quite high in strength. 4WD storage drawers that are made with timber are usually made with marine grade plywood, with highly stressed areas being re-enforced with steel bracing or truss rods. When this method of construction is implemented and used with heavy duty rollers, great strength can be achieved with drawer loadings of over 200kg.