Unpacked chatter machine (5)
I believe the answer is:
lathe
'machine' is the definition.
(lathe is a kind of machine)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for lathe that I've seen before include "Rotating machine tool" , "8 [TURNER]" , "Turner's tool" , "craftsman's machine" , "Machine for cutting, drilling or polishing" .)