A three-foot high machine, which was used to clock workers in and out at the mill, was donated to the centre this week.
It was donated by DS Smith Plc, which operated the mill until its closure in 1996.
Staff are now planning to open it up and get it working again, but little is known about its past.
Curator Brian Boulter estimated it dates to about the 1950s and appealed for former workers to come forward with any additional information or a time card from the era.
Contact the heritage centre, in Park Street, on 01628 780555.
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