Worker putting beam under overhang's end (7)
I believe the answer is:
grafter
'worker' is the definition.
(I have seen 'Hard worker ' mean 'grafter' so perhaps 'worker' could also mean 'grafter')
'beam under overhang's end' is the wordplay.
'beam' becomes 'rafter' (rafter is a kind of beam).
'under' means one lot of letters go next to another (in a down clue, some letters go below others).
'overhang's end' becomes 'g' (I can't explain this - if you can you should believe this answer much more).
'rafter' after 'g' is 'GRAFTER'.
'putting' acts as a link.
Can you help me to learn more?
(Other definitions for grafter that I've seen before include "One who works hard" , "Hard worker - corrupt operator" .)