carpentry square vs set square

carpentry square

noun
  • Synonym of carpenter's square 

set square

noun
  • A flat triangular piece of plastic or other material, having corners of precise angles, used in technical drawing 

  • A right angle tool used to determine if two surfaces join at a 90-degree angle, composed of two arms, usually made from metal. 

How often have the words carpentry square and set square occurred in a corpus of books? (source: Google Ngram Viewer )