mandrel

/ˈmændrəl/
noun
  1. A metal rod or bar used to hold or shape material being worked on, especially in machining or metalworking.
    • The machinist inserted the mandrel into the lathe to support the pipe.
    • A mandrel is essential for bending metal tubes without collapsing them.
    • He used a tapered mandrel to expand the ring to the correct size.
Synonyms
What does "mandrel" mean? | whatsthatwordmean | whatsthatwordmean