Sam Mendoza worked as a propmaker foreman on Star Trek: First Contact, along with John M. Carroll and Steve Morey and under the supervision of Dean Wilson. He later worked as a construction foreman on Star Trek: Insurrection (under coordination from Thomas J. Arp) and Star Trek Nemesis (under Richard J. Bayard).
Mendoza's first film was Paramount Pictures' The Golden Child (1986, starring Eddie Murphy). This was followed by John Huston's The Dead (featuring Colm Meaney) in 1987. Mendoza was a propmaker on both of these films. He went on to serve as propmaker foreman on Rising Sun (1993) and I Love Trouble (1994, starring Saul Rubinek). He was also a construction foreman on the films Final Analysis and Hoffa (both 1992) and a stage foreman on The Time Machine (2002), which, like Star Trek Nemesis, was written by John Logan.
Mendoza was a prop maker on Universal Pictures' 2006 musical comedy American Dreamz.
More recently he worked as assistant effects instructor on the fan-made internet series Star Trek: New Voyages episode "World Enough and Time" (2007).