IPA: /ˈsɜːrfɪsər/
KK: /ˈsɜrfɪsər/
A machine or tool that is used to smooth or finish a surface, often in construction or manufacturing.
The surfacer was essential for preparing the wood before painting.
Surfacer → It is formed from "surface" (from Latin *superficies*, meaning the outer face or appearance) and "-er" (meaning a person who). A surfacer is a person or thing that works on or deals with surfaces.
Think of someone who works on the 'outer face' ('surface') of something — that's what a surfacer does.