Australian car company Bolwell – best known for its iconic fibreglass sports cars – has applied its 48 years of experience with high-tech composite materials to the RV market and has come up with the Edge, a new caravan that marries aerospace technology with funky design.
It’s Bolwell’s first crack at the market and the company has gone in boots and all, producing a vehicle that is unlike any other on Australian roads.
While designer Vaughan Bolwell and his marketing brother, Owen, are certainly excited about the new van’s potential, the pair admit that they are unsure how it will be received when it debuts at Melbourne Leisurefest (September 30 to October 3).
The brothers are both new to the market and came to the project with a fresh vision and no pre-conceived ideas about how caravans should look and function. But should it gain acceptance, the way the Edge is built could revolutionise the industry.
Caravan World was given exclusive access to the Edge as Bolwell readied its prototype for Leisurefest, and discovered that while it looks a little like something from a science fiction film compared to the majority of vans on the road, it is backed up by sound engineering and sophisticated manufacturing for a millimetre-perfect fit.
STRENGTH WITHOUT WEIGHT
The van’s shell is made up of six sections which, once joined, work in a similar fashion to a Formula One car’s monocoque chassis, with each component relying on the other for strength.
There are two sides, nose and rear sections, plus floor and roof. The outer and inner side shells are bonded together by aircraft-grade adhesives with a foam insulation layer between them. “You can’t break the bond,” Vaughan said. “The fibreglass will break before the bond does.”
Bonding is preferred to screws, rivets and bolts. Glues bond body to chassis and fibreglass to fibreglass, with fillers and glues used for other procedures.
A variety of advanced materials and constructions are used in different sections to add strength or reduce weight. The side sections, for example, weigh just 65kg each. Kevlar, widely used in sail making for its tear-proof characteristics, is used in the roof, while carbon-fibre is applied in areas that need compressive strength, even in the drawers. Carbon-fibre is also employed in the van’s nose to reduce panel thickness without compromising strength.
Modified polypropylene fibre – a fabric so strong it’s used in motor racing to reinforce carbon-fibre – is used on the nose and skirt.
“You can hit it with a hammer,” Vaughan said. “It’s good for offroading because it will take hits from rocks.” E-glass, which is stronger than fibreglass, is also used and fibres are placed in different directions to gain particular benefits. A final coating of polyurethane adds another layer of stone-resistance.
A CURVY DESIGN
Despite its name, the Edge doesn’t have sharp angles or edges, as such. Instead, its shape is an amalgam of curves which, according to Vaughan, is an advantage. “All our patterns are CNC-milled, nothing is done by hand, but by computer,” he said.
“So we are able to get spot-on joints throughout, as well as stronger compound curves. That means a lighter product with the same strength as any other caravan. We did computer simulation on the structure to make sure it didn’t have any ‘red spots’ (weaknesses) from our Finite Element Modelling, and using that we were able to beef up red spots or change the design to suit.”
INTO THE WIND
Any caravanner knows that a swaying van behind a car is a scary sight, but Bolwell claims the Edge is aerodynamically efficient and handles better than a conventional van. Although the prototype is yet to be tested in a wind tunnel, we were told that open road testing has been positive.
Vaughan said aerodynamics have been largely ignored by traditional manufacturers, who have concentrated on getting vans stable heading into the wind and ignored the effects of side gusts. “I can’t see anyone really tackling that stability issue to try and make these things safer,” he said. “Instead, they tend to put big stabilisers onto tow balls, which does help but also adds weight.
“Most caravans have curved fronts and rears to some degree and are pretty good going forward, but the Edge has lateral curves as well. It has curves coming over the top of the roof for sideways gusts or wind from oncoming trucks.
“We’ve also got ‘tripping areas’, which trip the aerodynamic flow up to remain on the surface of the van, which ensures there are no vacuums created at the front or either side of the van. It goes well through the wind but it’s much more stable under tow.”
Similar to a racing car, what happens to air as it ‘leaves’ a vehicle can also affect handling, and Bolwell has addressed this. “There are very small radiuses on the back edge and small tripping areas to keep the air ‘attached’ to the van so there is no vacuum (following it); it keeps it steady,” Vaughan said.
SEALED TIGHT
The pop-up roof pivots from the front on a polyurethane hinge and is raised by two struts with an inside lock-in bar to prevent it accidentally falling. It is also watertight, a feature crucial to Bolwell. “We made a single-piece roof so there wasn’t any chance of leaks,” Vaughan said. “There are no rivets, everything is glued and sealed to prevent leaks.” The roof also includes a large pop-up skylight.
The double-glazed, polycarbonate front window has a carbon-fibre cover on struts. Beneath that, another lid covers a sealed, vented storage compartment for two gas cylinders, which is separate from the cabin. Also in the front boot is an 80L water tank with a gas/12V water heater. While slide-out galleys are nothing new, the Edge’s single-piece two-burner galley retracts into a sealed compartment under the queen-size bed to prevent cooking odours entering the cabin or bedding area. It is lockable and has a chopping board, sink and wind-deflector.
Above the galley is a 2x2m (6ft 6in x 6ft 6in) pull-out “Flexwing” awning, and the company is working on a larger optional annex and shower. The two large side windows are fixed for structural rigidity and security, and use a system of magnets set in the fibreglass laminate window surround for curtain attachment, allowing any configuration of curtain. The hatched door looks almost like it came off a submarine; it is very strong and functional. Running through it is a steel frame with a steel security mesh on the inner door. All external latches are compression fixtures with double seals to keep dust out.
SIZE AND STRUCTURE
The Edge is bigger than it appears in two dimensions, with a length of 5.4m (17ft 8in) and a maximum interior height of 1.96m (6ft 3in). “It’s higher than most caravans where it needs to be,” Vaughan said. Interior space is well utilised, with wheel arches used as storage, a fold-out table located under the bed, a single-burner cooktop and three-way 104L fridge, a marine-grade audio system, and wardrobe and three large flush-fitting drawers. All fittings are fibreglass with easy-clean surfaces and the carpet is marine-grade and press-studded to the floor. “You could almost hose out the inside of the van to clean out bulldust,” Owen said.
The cabin is bonded to a chassis made from 1m galvanised steel box tubing and has a Treg hitch, fully independent trailing-arm suspension with Pedders coil springs, Koni shock absorbers and 10in electric drum brakes.
“The chassis and suspension took two years to develop with our automotive and aerospace engineers and is designed to go offroad,” Vaughan said. “The A-frame runs deep into the chassis, almost to the wheels, it’s not just stuck on the front, and the trailing arms are triangulated to the centre for lateral stability.”
Bolwell expects the Edge will have a Tare of 1000kg. “For something this size you’re normally looking at about 1300kg, so you don’t need a big 4WD to pull it. We can tow it with our Subarus,” Vaughan said. The lighter weight also results in fuel economy benefits.
But will the unusual, $45,000 (projected) Edge sell?
“It’s a big punt, but as far as the general user items like the fridge or cooker go, they’re stock caravanning gear that everyone already uses so there is nothing strange or scary there,” Owen stressed. “We’re looking at the retiree or semi-retiree markets. They may not be hardcore 4WD users, but they want to see Australia in something that’s not going to cost them too much. But we might find out that 30-year-old mountain bikers want to take it away.
“We will not know until we get it out there, but caravan owners are changing. They buy furniture from Ikea, they’re internet-savvy, they have Facebook account.
“This is a Baby Boomer van. It’s not your granddad’s van; it’s a cross-over campervan. My retired next door neighbours are avid caravanners and they said they would buy this in a heartbeat because it’s light, it won’t leak and is easy to clean, which are their main criteria.”
Bolwell Car Company, Mordialloc, Vic, 3195, (03) 9770 8572, http://www.bolwellcarcompany.com
BOLWELL EDGE
GENERAL
Body length 4.75m (15ft 7in)
Overall length 5.41m (17ft 9in)
External width 2.1m (6ft 10in)
Internal length 4.1m (13ft 5in)
Internal width 2.07m (6ft 9in)
Internal cabin height (roof down)
1.6m (5ft 3in)
Internal cabin height (roof up)
1.96m (6ft 3in)
Travel height: 2.3m (7ft 6in)
Rear body exit angle 15°
Ground to chassis clearance (unloaded)
0.4m (1ft 4in)
Nameplate ATM TBA (approx 1350kg)
Nameplate Tare TBA (approx 1000kg)
Ball weight TBA (approx 135kg)
FEATURES
Mattress Queen
Fridge 104L Dometic three-way
Fresh water 80L
Gas cylinders 2 x 4.5kg
Battery 12V 100Ah deep-cycle
Charger Ctek
Hot water 12V/gas
Exterior hotplate Dometic two-burner
Sunroof Dometic
Driving lights LED
Interior lights LED
Front window Double glazed
polycarbonate
Flexwing awning 2.1x1.95m
(6ft 11in x 6ft 5in)
CHASSIS
Body Fibreglass/synthetic composite
with foam insulation
Chassis RHS steel hot dipped
galvanised
Hitch Treg
Jockey wheel Al-Ko
Corner stabilisers Al-Ko quick-drop
Brakes Al-Ko 10in electric drum
Tyres Cooper Discoverer ATR
Suspension Independent trailing arm,
coil springs
Shock absorbers Koni
Spare wheel Rear mount
STORAGE
External front compartment 820L
External offside compartment 343L
Seat compartment 2 x 170L
Kitchen shelving 133L
Kitchen drawers 249L
Open kitchen storage 45L
Wardrobe 253L
Under-bed compartments 687L