Sentence:  The beds shall be <WSD>scabbed</WSD> off to give a solid bearing, no pinning shall be admitted between the backing and the face stones and there shall be a good square joint not exceeding one inch in width, and the face stone shall be <WSD>scabbed</WSD> off to allow this. 
Meaning of the word marked with <WSD> tags:  To remove part of a surface (from).