Safety inspectors investigated the firm and its factory in the town where two colleagues found 45-year-old Michael Lohaza dead by the machine he was operating.
Mr Lohaza, from nearby Ashton-on-Ribble, had become trapped in the lathe at Autoy Ltd's site in Castleton Road in January 2009, in what is just the latest in a series of work accidents
He was discovered by staff in a small building near the main workshop where he was working on his own
Mr Lohaza was an Autoy employee for 28 years.
Preston Crown Court heard Mr Lohaza was killed when he became entangled on a one-metre-long metal screw, while cutting its thread on a lathe. The screw was rotating approximately 200 times every minute.
Autoy Ltd was prosecuted by HSE for failing to ensure Mr Lohaza's safety, and for failing to assess the risks workers faced while operating lathes.
The company pleaded guilty to breaching Section 2(1) of the Health and Safety at Work etc Act 1974 and Regulation 3(1)(a) of the Management of Health and Safety at Work Regulations 1999.
Autoy Ltd was fined £17,500 and ordered to pay £12,251 costs at Preston Crown Court on 24 September.