Causes of Propeller Roughness

Fouling can be various kinds of  bio matter, ranging from a thin film to big barnacles.

 The propeller will develop a rough layer calcareous chalk as a by product of the cathodic protection system.

This typically happens if there are objects in the water (drift wood etc.). These objects will be sucked into the propeller and damage it.

Improper Maintenance

The results of improper maintenance are often scratches in the surface from a rough diamond disc polish. These very hard discs are necessary when it has been to long since the last propeller polish.