Abstract: An anchor assembly for a downhole tool has upper and lower frictional engagement member for engaging with an inner wall of the casing. The upper frictional members are spring-tensioned, while the lower frictional engagement members slide, to certain degrees, in relation to a longitudinal axis of the anchor assembly. At the same time conical engagement between the lower frictional members and the supporting surface causes the lower frictional members to extend outwardly and engage the inner surface of the casing. As a result, the working tool, for instance a sand cutter secured to the anchor assembly is stabilized in the casing, and an even cut may be performed.