Reset pin springs in these mass production machines (8,7)

I believe the answer is:

printing presses

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'reset pin springs' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'these mass production machines' is the wordplay.
'these mass production' becomes 'printing' (printing is a kind of production. I am not sure about the 'mass' bit.).
'machines' becomes 'presses' (press is a kind of machine).
'printing'+'presses'='PRINTING-PRESSES'

'in' acts as a link.

Can you help me to learn more?

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

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