Polycrystalline diamond cutters are ultra-hard tools used for oil and gas drilling. They are produced by sintering diamond particles at High Pressure (5.5+ GPa) and High Temperature (1300+ K). After synthesis, the cutter is returned to room temperature and pressure. The significant mismatches in thermal expansion coefficient and stiffness between the diamond table and the tungsten carbide substrate result in residual stresses. The magnitude and distribution of these residual stresses is believed to impact cutter failure rate. We have produced finite element models to estimate these residual stress but previous measurements at Engin-X show significantly lower strains than predicted. The proposal is to investigate the effect of varying different manufacturing conditions on the residual stress, to identify the most important factors determining the magnitude and distribution of the stresses