Bank clerk losing head conceals reputation of craftsman (9)
I believe the answer is:
enameller
'craftsman' is the definition.
(I've seen this before)
'bank clerk losing head conceals reputation' is the wordplay.
'bank clerk' becomes 'teller' ('teller' can be a synonym of 'bank clerk').
'losing head' means to remove the first letter.
'conceals' is an insertion indicator.
'reputation' becomes 'name' (name is a kind of reputation).
'teller' with its initial letter removed is 'eller'.
'eller' going around 'name' is 'ENAMELLER'.
'of' is the link.
(Other definitions for enameller that I've seen before include "One decorating with glassy coatings" , "Craftsman" , "One applying vitrified coating" , "Decorative artist" , "Who lacquers" .)