Go over part of transverse beam (10)

I believe the answer is:

crosspiece

'transverse beam' is the definition.
(beam of wood)

'go over part' is the wordplay.
'go over' becomes 'cross' (to cross over).
'part' becomes 'piece' (piece is a kind of part).
'cross'+'piece'='CROSSPIECE'

'of' acts as a link.

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

I've seen this clue in the Sydney Morning Herald.

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