In one aspect, a scraper blade for a conveyor belt is disclosed that provides improved strength and durability of a connection between a resilient blade body and an insert molded in situ with the blade body. The blade body has an upper portion with a scraping tip and a lower portion with a pair of laterally spaced depending leg portions. The insert has a pair of laterally spaced side wall portions with variable wall thicknesses and laterally outwardly facing sides that extend along laterally inwardly facing sides of the blade body leg portions. Each insert side wall portion and the blade body lower portion include a plurality of recesses having an undercut configuration and a plurality of projections extending laterally and filling the corresponding recesses in which the projections are received to keep the blade body and the insert connected together under loading during conveyor belt operations.