Wall construction
In Australia
most Caravan Manufacturers build their frames from glued and stapled timber.
The problem
with this method is that condensation forms on the inside of the cladding as
well as the outside, in
temperature changes like dew in the morning. This condensation attacks the
wood in the exterior walls
causing the wood to become prone to swelling, fungus, dry rot; as well as
rusting the staples and
screws.
Some of the
methods used to combat these conditions are the use of treated timbers and
so called
"space age" glues to affix the cladding.. Unfortunately the copper that is
used to treat the wood can
react with aluminium cladding causing corrosion, and glues will only bond to
the immediate surfaces
of the wood. Surface adhesion is not much of a structural bond, particularly
when moisture is attacking
the material.
The 1/4 of the
industry that have made the transition to aluminium are building with very
thin materials, such as 1mm "C" channel with a single punch rivet. The
material is so light, it is like riveting two aluminium cans together, you
could tear it apart with your bare hands. This is why wood
caravan builders can say that aluminium frames are no good. If that was the
only way you could build aluminium frames we would agree.
We use 2 and 3mm structural box section lapped onto 3mm angle for a total of 5mm thick at the joints. The frames are then aircraft style double counter sunk diagonally riveted. Then the frames are welded on both sides to freeze the joint. Roof sections utilize 2.5mm box section thick with a taper, and then are insulated with 3 inches of cooler board. Corner wall and roof section are also through bolted with Nylock nuts and stitch welded.
The entire wall and roof assemblies are designed to flex like an aircraft wing but the joints will not move! The joints are 180% stronger than the material itself.
Our frames are the strongest caravan wall and roof frames in Australia and that is why we have had up to 9 men on the roof of one of our vans. If you have a look at our Wall Frame Crew in one building standing on a frame with no bulkheads or panelling in place, you can see how in the last eight years, several Bushtrackers involved in accidents have rolled over and remained structurally intact. These vans were repaired and are still on the road today.
We build "Land Yachts" to
last a lifetime. These wall frames are just another reason why Bushtracker
is Number One in the Outback.
Chassis | Suspension | Wall construction | Exterior features | Interior features
