palette knife vs putty knife

palette knife

noun
  • In painting, a small, edge-less, more or less flexible steel blade used to mix paint on a palette and sometimes to apply paint to a surface. 

putty knife

noun
  • A similar tool with a wide, flat blade used by painters, plasterers, and carpenters to spread putty to fill holes and cracks. 

  • A hand tool with a flexible blade used by glaziers to apply putty to seal window panes to the frame and mullions. 

How often have the words palette knife and putty knife occurred in a corpus of books? (source: Google Ngram Viewer )