Fake smithy (5)
I believe the answer is:
forge
This clue is a double definition.
'fake' is the first definition.
(forge can mean to fake or counterfeit)
'smithy' is the second definition.
(synonyms)
(Other definitions for forge that I've seen before include "Shape by heating and hammering, as smith does" , "Smith's workshop" , "Smithy; falsify" , "Blacksmith's premises" , "Smith's workplace" .)