Length change of shoe last footstep in series

The article presents results of studies of changes in the parameters of shoe last footstep of women's shoes with a particularly high heel. The benchmark analysis of experimental and theoretical data of the change in the amount of shoe last (insole) footstep shear of the shoe in the heel part is made. The shear depends on shoe size and pitch. It is found that the value of the insole shear in the heel part in the series varies insignificantly when the pitch remains unchanged. An increase in the height of the heel part elevation of the shoe increases the insole shear in the extreme dimensions of the series by 5-6 mm. In the series of shoe lasts of high-heeled shoes, the insole shear is 9-11 mm. The constant value of functional allowance set by GOST for shoe lasts in the toe part violates the basic principle of grading, the principle of similarity, which can lead to the fact that in shoes with extra high heels the length of the shoe last footstep will be less than the length of the foot, which is not permissible. The research detected such cases in practice, which proves the need to increase the size of the functional allowance in shoes with extra high heels. The suggestion is made to introduce a system of footwear numbering uniform for all countries, taking into account the wide development of Internet commerce.