US Patent 7069616 Scraper

As shown in FIG. 1, there is a paint scraper 1, comprising support means 2 supporting a blade portion 3, the blade portion having a scraping edge 5 with undulations, the undulations being arranged to match corrugations of a sheet of corrugated iron; the scraper 1 being formed such that when it is in use the blade portion can be arranged against the sheet of corrugated iron such that the blade portion extends from the sheet in a substantially perpendicular fashion with the undulations of the scraping edge 5 aligned in complimentary fashion with undulations of the sheet, and wherein a substantial part of the scraping edge can then be scraped across the sheet to substantially effectively remove paint flakes or dirt from the sheet.