Attach the rudder to the stern. Making hinges.   The plastic hinges will be a weak point. To fix this, copper pins of diameter 1mm are placed. Holes are drilled in the stern at the right place. A knock with the hammer, and the rudder is well fixed. This will not come loose anymore.   Finish the hinges    A light layer of metal paint is first applied under the white layer.  The upper hinge is painted black.