Abstract: A drum-type rotary scraper, for use in a corner, scraping a surface by the snapping reformation of elastically restrained portions of flexible fingers deformed from their normal circular path by the constraint of the planes forming the corner.By way of an example, a cylindrical bird-cage broom whose tips rotate bluntly and ineffectively against a first plane surface while the drum surface of the fingers immediately adjacent the tip ends, in deforming and scraping on the second and snapping onto the third of surfaces defined by the intersection of three planes at right angles, removes paint from two of these relatively inaccessible surfaces.

Abstract: A rotary scraper with fingers striking the work surface at a lagging angle, thus removing material by impact rather than by a scraping action. By way of an example, a wire brush with pivoted fingers that are restrained and unable to fully centrifugally extend radially.