Strong cord from California that gaffer uses temporarily at first (6)
I believe the answer is:
catgut
'strong cord' is the definition.
(cord made from animal intestines)
'california that gaffer uses temporarily at first' is the wordplay.
'california' becomes 'ca'.
'at first' suggests taking the first letters.
The first letters of 'that gaffer uses temporarily' is 'tgut'.
'ca'+'tgut'='CATGUT'
'from' is the link.
(Other definitions for catgut that I've seen before include "Natural suture cord now largely replaced by artificial polymer" , "Cord used for stringing instruments and rackets" , "Strong cord used in surgery and violin strings" , "Material used for violin strings, for example" , "Traditional violin string" .)