Abstract: A method of installing foil type electrical strain gages wherein adhesive is applied and the gage pressed about is periphery to provide a fluid pressure seal. The gage and the structure are then pressurized directly in a fluid pressure vessel chamber and the pressure maintained while the vessel is heated to provide full curing of the adhesive.

Abstract: The performance and condition of a tool, workpiece or machine tool is sensed during machining operations by securing a single or plural strain gages to the tool holder. To increase the sensitivity of the strain gages on stationary tool holders, the tool holders are contoured to provide locations of higher strain in which the strain gages are attached. A single or plural strain gages are positioned to sense the combined effect of different strains such as axial thrust and torque and are electrically connected to provide a single Wheatstone bridge output "signature" which may be monitored to detect a defective operation. In rotating tools, the single "signature" output greatly reduces the coupling equipment such as rotary transformers and also reduces the monitoring equipment. A unique arrangement of a single strain gage or alternatively a plurality of gages enables monitoring of both torque and thrust simultaneously.