Construction at stake. Sews a hem, but don’t work too fast (5,5,5)

I believe the answer is:

haste makes waste

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'don't work too fast' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'construction at stake sews a hem' is the wordplay.
'construction' is an anagram indicator (answer constructed from certain letters).
'at'+'stake'+'sews'+'a'+'hem'='atstakesewsahem'
'atstakesewsahem' with letters rearranged gives 'HASTE MAKES WASTE'.

'but' is the link.

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

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