Base, centre for ironworks, was heaving (8)
I believe the answer is:
'base' is the definition.
'centre for ironworks was heaving' is the wordplay.
'centre for' indicates the central letters.
'was heaving' becomes 'retched' (retch can mean to heave or throw up).
The central letter of 'ironworks' is 'w'.
(Other definitions for wretched that I've seen before include "misery" , "Abject" , "Poor" , "Very unhappy, miserable" , "awful" .)