RAFT
How is the rafting boat made?
The structure
The rafts designed to deal with river rapids consist of at least six insulated inflatable chambers, which allow navigation even if one of the chambers is punctured. These sections are: one for the bottom, four for the perimeter tubes and one or more for the central sausages. The central sausages are used to keep the structure rigid and avoid excessive twisting. Their number varies depending on the sizeof the boat. Generally they range from two to four.
Circular holes made on the junction between the bottom and the perimeter tubes allow the waterthat pours into the boat to flow out, making the raft self-draining. The first rafts did not have this feature and one of the participants had to empty the boat using a bucket.
A perimeter rope is fixed along the perimeter by means of rings, useful for getting back on the boat and for keeping in the rapids. Foot cap, a kind of slipper, are glued to the bottom to allow the rafter to anchor with his feet to the boat.
The materials
There are two materials most used in the construction of rafts: PVC and HYPALON.
PVC
It is the vinyl chloride polymer, one of the most consumed plastic materials. The resistance is given by the fabric embedded in the plasty.
The Hypalon
Even stronger than PVC, the material is a very versatile synthetic rubber made of polyethylene (CSPE) (CSM) known for its resistance to chemicals and UV rays.
The conduction
The main tool for propulsion is the rafting paddle.
There are two techniques to guide a raft and its crew.
A paddle
The driver is seated in the rear on one side and uses a normal raft paddle as a rudder.
Rowing
A tubular structure in iron or aluminium is fixed to the raft by means of straps. This structure can be positioned centrally or in a queue. Its function is to support a seat for the guide and two rowlocks to which as many oars are applied. The oars are very long and allow you to create advantageous leverage for the conductor. Generally used on large rivers, this system allows for greater control during navigation.