A method of assembling at least a part of a wind turbine blade by joining a first element of the wind turbine blade with a second element of the wind turbine blade, the first element comprising a first aerodynamic shell having an inner circumference, and the second element comprising a second aerodynamic shell having an outer circumference, the first aerodynamic shell and the second aerodynamic shell comprising a resin infused fibre material, the method comprising the steps of: a) manufacturing the first element, the first element having the first aerodynamic shell tapered in thickness around the inner circumference of the first element towards a first end, defining a first tapered section, b) manufacturing the second element, the second element having the second aerodynamic shell tapered in thickness around the outer circumference of the second section towards a second end, defining a second tapered section, c) aligning the first element and the second element, the first end facing the second end, d) inserting the second tapered section at the second end into the first tapered section at the first end, and e) joining the first element and the second element with adhesive, wherein step a) of manufacturing the first element comprises at least one verification step of a desired geometry of the first tapered section by measuring against a master tool reflecting the desired geometry of the first tapered section and wherein step b) of manufacturing the second element comprises at least one verification step of a desired geometry of the second tapered section by measuring against a master tool reflecting the desired geometry of the second tapered section. the first element comprising a first aerodynamic shell having an inner circumference, and the second element comprising a second aerodynamic shell having an outer circumference, the first aerodynamic shell and the second aerodynamic shell comprising a resin infused fibre material, the method comprising the steps of: a) manufacturing the first element, the first element having the first aerodynamic shell tapered in thickness around the inner circumference of the first element towards a first end, defining a first tapered section, b) manufacturing the second element, the second element having the second aerodynamic shell tapered in thickness around the outer circumference of the second section towards a second end, defining a second tapered section, c) aligning the first element and the second element, the first end facing the second end, d) inserting the second tapered section at the second end into the first tapered section at the first end, and e) joining the first element and the second element with adhesive, a) manufacturing the first element, the first element having the first aerodynamic shell tapered in thickness around the inner circumference of the first element towards a first end, defining a first tapered section, b) manufacturing the second element, the second element having the second aerodynamic shell tapered in thickness around the outer circumference of the second section towards a second end, defining a second tapered section, c) aligning the first element and the second element, the first end facing the second end, d) inserting the second tapered section at the second end into the first tapered section at the first end, and e) joining the first element and the second element with adhesive, wherein step a) of manufacturing the first element comprises at least one verification step of a desired geometry of the first tapered section by measuring against a master tool reflecting the desired geometry of the first tapered section and wherein step b) of manufacturing the second element comprises at least one verification step of a desired geometry of the second tapered section by measuring against a master tool reflecting the desired geometry of the second tapered section.