Metal used in rake, as usual (7)
I believe the answer is:
routine
'as usual' is the definition.
(I've seen this before)
'metal used in rake' is the wordplay.
'metal' becomes 'tin' (tin is a kind of metal**).
'used in' is an insertion indicator.
'rake' becomes 'roue' ('roue' can be a synonym of 'rake').
'tin' going within 'roue' is 'ROUTINE'.
(Other definitions for routine that I've seen before include "Method" , "Unvarying set of actions" , "Normal procedure" , "Procedure regularly followed" , "habit" .)