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.