Method of bonding a shear web (50) to a wind turbine blade shell (75) and the obtained blade, wherein the shear web (50) comprises a web and a mounting flange (56) oriented transverse to the web (50). The method involves: providing a seal (66, 68) on the mounting flange (56) of the shear web (50) such that when the mounting flange (56) is positioned against the blade shell (75), a cavity (76) is defined by the seal between the mounting flange (56) and the blade shell (75). The air of the cavity (76) is then evacuated and adhesive is injected into the cavity (76). The use of pieces (80) to keep the distance between the mounting flange (56) and the blade shell (75) is preferred.