Ball end magnetorheological finishing (BEMRF) is an advanced finishing method employed for super finishing of flat, curved, intricate and complex surfaces. The surface finish achieved in BEMRF process is governed by machining parameters and fluid parameters. A main contributor towards super finishing by BEMRF process is the work gap. A constant work gap ensures a uniform finishing operation throughout the entire surface; however, there are many cases wherein the work gap between tool tip and workpiece varies over the surface due to geometric form deviations induced by preceding manufacturing process or linear positioner having a tilt error. This paper describes a method to keep a constant work gap for finishing in BEMRF process. A confocal sensor is used to scan the surface in order to detect any height deviations that prevent a constant work gap. Experimental results show a considerable improvement in the surface quality while finishing with perpetuated work gap.