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When the carving process is finished, three press-in connectors are mounted in each blade.
A press-in connector, illustrated on figure 6.14, is a plate with teeth along the perimeter,
which may be pressed into the wood.
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Figure 6.14: Press-in connector [62]
The connectors enhance the bearing strength of the joint connection [31, p. 92]. It is rec-
ommended to install the press-in connectors by hammering them into the wood using a
stiff plate as support. It is important to ensure that the centre hole of the press-in connec-
tor is concentric to the bolt hole of the blade [31, p. 96].
When hand-carving the blades the repetitive accuracy is relatively low and it is therefore
necessary to verify the quality of the manufacturing process by inspecting the blade imbal-
ance. This is done in two steps: The first is to make sure that all three blades have the same
weight and the same weight-distribution. This is done by mounting a bracket with two
spikes on the root of the blade using two M12 bolts, as shown on figure 6.15. A third spike
is placed on a scale and its output reading is noted. If the blades have been carved thor-
oughly the output on the scale will be the same for all three blades.
Figure 6.15: Balancing the blade
When the individual blade balance has been checked, the blades are mounted onto the
front disc of the generator. Here it is checked that the distances L of figure 6.16 are all
equal.