Coronet pioneers trick timber walls

Melbourne caravan builder first to adopt time-saving, lightweight plywood walls

In a tilt back at Australian caravan manufacturing history, where bondwood caravans once ruled, Melbourne’s Coronet RV is pioneering a new locally-manufactured full thickness lightweight plywood wall system on its latest pop-top and full height caravans that are set to make their public debut at the Victorian Caravan Superhow from February 22-29.

Measuring 18mm thick without cladding and approximately 25mm thick with smooth fibreglass external and ply inner lining, the walls offer unique advantages over framed or composite insulated walls.

Coronet RV boss Andrew Phillips estimates that fitting the walls, which are formed by pressing laminates together using 100 per cent waterproof and fire retardant adhesives, will cut build time from chassis to delivery from around three to four months with framed walls to as little as eight to ten days.

This represents a major saving in inventory costs and cash flow for the manufacturer, while also allowing Coronet RV to offer a large degree of customisation much later in the order process than with other construction methods.

Unlike most caravan walls, Worthington Industries located in the Melbourne suburb of Bayswater North manufactures the large one-piece Complite composite panels to Auto Cad drawings. Used successfully in trains, trams and in the building industry, Worthington also has the capability to produce seamless panels to almost any length, given the space to handle them.

Family-owned for 40 years and AS/NZS ISO 9001 compliant, Worthington already has a strong connection with the Australian caravan and RV industry, currently supplying around 40 manufacturers including Coronet with its single-piece Ezyfloor flooring in diameters from 12mm to 19mm.

However, whereas the floors are formed by joining sections, the walls come out of their machinery in a single formed structure, with the cut-outs for windows and doors perforated and ready to be punched out.

The company also produces one-piece walls with foam cores for a number of caravan manufacturers, but by choosing the thickest-available full thickness lightweight ply for its walls, Coronet RV has in many ways stolen a march on its rivals.

After bolting a 12mm Worthington ply floor to its G&S Chassis, Coronet then builds its pop-tops and caravans from the inside out, adding the furniture, special buttressing on pop-top models, plumbing, gas fittings and wiring.

The walls are then one of the last major assembly tasks and they and the furniture are bolted securely to the floor to create what effectively is a monocoque structure.

By using one-piece walls, Andrew Phillips estimates that it cuts a day’s work for two people from the production time of a typical caravan, but the real advantage of the full-thickness ply walls for Coronet is that the internal furniture and even power points can be fixed anywhere, rather than in predetermined places, where timber would have to be added for this purpose in full foam composite walls.

Effectively this allows the customer to make changes in many areas, including even moving walls, cupboards and adding power points, within two weeks of taking delivery – an evolutionary idea for a mainstream caravan manufacturer.

On Coronet’s side, it also dramatically reduces inventory costs and the factory space required, as their vans are built ‘just in time’. Coronet builds around four vans a week at its compact Melbourne factory.

Interestingly, Phillips doesn’t believe there is any significant weight penalty in the solid walls compared with the slightly larger diameter (29-30mm) foam composite panels, nor has he found any discernable difference in thermal efficiency in hot weather.

“With pop-tops you release most of the hot air when you lift the roof and unzip the upper mesh vents anyway,” he said.

Coronet’s move to this type of wall construction doesn’t automatically mean that other caravan manufacturers will follow suit.

As Worthington Industries CEO Steven Oliveros pointed out, different Australian caravan manufacturers have their preferred means of construction; some preferring aluminium to fibreglass outer cladding; some choosing fibreglass or even vinyl over ply for the interior finish and others specifying custom composite walls that can incorporate timber strengthening and wiring channels.

Cornet is moving its entire 2017 pop-top and full height caravan production over to the new full-thickness ply walls, with traditional-looking ribbed aluminium cladding standard on its entry-level ST touring models, while smooth fibreglass outer cladding will be optional on all

FS (Fashion Statement) models and standard on top-of-the-range XT (X-Trail) off-road vans.

Coronet pioneers trick timber walls

Tags