Abstract <p>The composition and features of the manufacture of specimens of epoxy-sand composite used during the field repair of road-building machines are considered. The results of determining the influence of the preparation quality of a metal surface on resistance of the epoxy-sand coating to aggressive environments are presented. It is shown that the quality of the filler preparation does not affect the coating resistance to aggressive environments. It was found out that specimens with a pre-treated surface before applying the epoxy-sand composite coating showed the best resistance to aggressive environments.</p>