An apparatus for measuring forces acting on a tubing string within a wellbore, comprising a body including a central passage and an internal void radially offset from the central passage. The alkali conducting separator may be a substantially non-porous ion conducting material wherein the alkali conducted is Na, K, or Li. The pump is coupled to the storage tank by a delivery line. Such a correction step comprises providing a wafer referred to as spacer wafer, wherein that spacer wafer is structured for at least partially compensating for said manufacturing irregularities. Thus, a resistance during cutting can be small. A second lead extends from a stripe height of the sensor into the head assembly.