Preparation grades: scraping and wire-brushing

It is assumed that prior to treatment the steel surface has been cleaned of dirt and grease - and that the heavier layers of rust have been removed by chipping.

St2

Thorough scraping and wire-brushing machine brushing grinding etc The treatment removes loose millscale rust and foreign matter. Finally the surface is cleaned with one of these media: a vacuum cleaner; clean dry compressed air; or a clean brush. As a result the surface should have a faint metallic sheen and the appearance corresponding to the prints designated St2.

St3

Very thorough scraping and wire-brushing grinding etc. surface preparation as for St2 but much more thoroughly. After removal of dust the surface should have a pronounced metallic sheen that corresponds with the prints designated St3.