A method for estimating thread parameters of a part which moves relative to a stage and a plurality of sensors which measure the amount of radiation contained in directed planar portions of radiation unobstructed by the part is provided. The amount of radiation is representative of a respective geometric dimension of the part. The method includes obtaining calibrated part data from an inspection region between position limits of the stage. The calibrated part data includes calibrated sensor data for each sensor of the system and its corresponding coordinate system. The method further includes processing the calibrated part data to obtain intermediate data. The method still further includes analyzing the intermediate data to produce estimates of the thread parameters of the part.