1996 Daewoo Cielo Scraping sound from front wheels

I have been driving a Daewoo 1996 Cielo GLE for the last several years (it was a dream car). Lately, after driving for around 30-45 minutes, on application of the brakes a scraping sound emanages - it is distinctly metallic in nature. Several mechanics have tried to isolate the issue, in vain. The brake assemblies have been replaced multiple times under that suspicion, to no effect. Any advice in this regard would be appreciated.

CAR REPLACEMENT IS NOT AN OPTION AT ALL!!!