A man of iron who doesn't make good money? (6)
I believe the answer is:
forger
'a man of iron who doesn't' is the definition.
The answer and definition can be both people as well as being singular nouns.
I also know that 'iron' relates to this answer.
'make good money?' is the wordplay.
'make' becomes 'forge' (forging is a kind of making).
'good money?' becomes 'r' (I am not sure about this - if you are sure you should believe this answer much more).
'forge'+'r'='FORGER'
(Other definitions for forger that I've seen before include "Blacksmith" , "Person who makes phoney bank notes" , "who makes a lot of money?" , "Maker of false bank-notes" , "Ironworker" .)