Complex sentence: Several tools have been created specifically for scratchboard; however any sharp implement will do though a range of blades of different thicknesses allows the removal of more or less of the ink at will.
Split into simpler sentences: Several tools have been created specifically for scratchboard; however any sharp implement will do. It is good to have a range of different thicknesses in your blades so that you can remove more or less of the ink at will.