A system and method to correct for deposition errors during a robotic welding additive manufacturing process. The system includes a welding power source to sample instantaneous parameter pairs of welding output current and wire feed speed in real time during a robotic welding additive manufacturing process while creating a current weld layer of a 3D workpiece part. An instantaneous ratio of welding output current and wire feed speed are determined for each instantaneous parameter pair. A short term running average ratio is determined based on the instantaneous ratios. A relative correction factor is generated based on at least the short term running average ratio and is used in real time while creating the current weld layer to compensate for deviations in a deposit level from a desired deposit level for the current weld layer.