A method of producing a hem flange bond, comprising at least the steps of a) applying a one-component thermosetting epoxy resin composition to an inner panel or to an outer panel; b) contacting the one-component thermosetting epoxy resin composition with the inner panel or the outer panel; c) crimping the outer panel around the inner panel, such that the one-component thermosetting epoxy resin composition is present within the hem flange; d) compressing the hem flange; e) introducing thermal energy into the one-component thermosetting epoxy resin composition, wherein the one-component thermosetting epoxy resin composition comprises: - 20-60% by weight, based on the total weight of the one-component thermosetting epoxy resin composition, of at least one epoxy resin A having an average of more than one epoxy group per molecule, comprising at least one liquid epoxy resin A1 , preferably at least one solid epoxy resin A2 , and preferably at least one epoxy group-bearing reactive diluent A3 , where the proportion of liquid epoxy resin A1 is 10-100% by weight, based on the total weight of epoxy resin A; - at least one latent curing agent for epoxy resins B; - 10-40% by weight, especially 20-30% by weight, based on the total weight of the one-component thermosetting epoxy resin composition, of at least one toughness improver D which is selected from the group consisting of terminally blocked polyurethane polymers D1 , liquid rubbers D2 and core-shell polymers D3, and is preferably terminally blocked polyurethane D1 ; - 4-12% by weight, based on the total weight of the one-component thermosetting epoxy resin composition, of at least one room temperature solid, crystalline polyester polyol PP . a) applying a one-component thermosetting epoxy resin composition to an inner panel or to an outer panel; b) contacting the one-component thermosetting epoxy resin composition with the inner panel or the outer panel; c) crimping the outer panel around the inner panel, such that the one-component thermosetting epoxy resin composition is present within the hem flange; d) compressing the hem flange; e) introducing thermal energy into the one-component thermosetting epoxy resin composition, - 20-60% by weight, based on the total weight of the one-component thermosetting epoxy resin composition, of at least one epoxy resin A having an average of more than one epoxy group per molecule, comprising at least one liquid epoxy resin A1 , preferably at least one solid epoxy resin A2 , and preferably at least one epoxy group-bearing reactive diluent A3 , where the proportion of liquid epoxy resin A1 is 10-100% by weight, based on the total weight of epoxy resin A; - at least one latent curing agent for epoxy resins B; - 10-40% by weight, especially 20-30% by weight, based on the total weight of the one-component thermosetting epoxy resin composition, of at least one toughness improver D which is selected from the group consisting of terminally blocked polyurethane polymers D1 , liquid rubbers D2 and core-shell polymers D3, and is preferably terminally blocked polyurethane D1 ; - 4-12% by weight, based on the total weight of the one-component thermosetting epoxy resin composition, of at least one room temperature solid, crystalline polyester polyol PP . <EOS>