Angry bit of writing making one beam (10)

I believe the answer is:

crosspiece

'one beam' is the definition.
(crosspiece is a kind of beam)

'angry bit of writing' is the wordplay.
'angry' becomes 'cross' (I've seen this before).
'bit of writing' becomes 'piece'.
'cross'+'piece'='CROSSPIECE'

'making' is the link.

(Another definition for crosspiece that I've seen is " Beam".)

I've seen this clue in The Telegraph.

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