Draw together writer's material over time (4)
I believe the answer is:
knit
'draw together' is the definition.
(I've seen this before)
'writer's material over time' is the wordplay.
'writer's material' becomes 'ink' (I've seen this in other clues).
'over' is a reversal indicator.
'time' becomes 't' (abbreviation).
'ink' backwards is 'kni'.
'kni'+'t'='KNIT'
(Other definitions for knit that I've seen before include "(Bone) heal; contract (brows)" , "get together" , "Form by looping and entwining wool etc" , "Link closely together" , "Make woollen garments" .)