Have a go at empty abstracts on canvas (6)
I believe the answer is:
assail
'have a go at' is the definition.
(I've seen this before)
'empty abstracts on canvas' is the wordplay.
'empty' says to hollow out the word (remove centre letters).
'on' says to put letters next to each other.
'canvas' becomes 'sail' (a sail is a piece of canvas).
'abstracts' with its centre removed is 'as'.
'as'+'sail'='ASSAIL'
(Other definitions for assail that I've seen before include "Beset" , "storm" , "Molest or harass" , "Sudden attack" , "Set upon" .)