Research on Recoating Process in High-Resolution Stereolithography System

To resolve the problem that thickness of resin layer increases with the object height during building process in piston recoating system, experimental investigations were performed to establish the model describing the relationship of recoating layer thickness with object height and blade speed by using response surfaces methodology. According to the model, a novel recoating process with dynamically optimized blade speed is proposed. Verifying experiment results show that the problem that the thickness of resin layer increases with the height of objects is solved, and experiment results indicate that the new recoating process reduces the difference between maximum and minimum thickness of resin layer from 27 mum to 6.9 mum, and experiment results also demonstrates that step position error is reduced from 494 mum to 66 mum. The new recoating process provides an effective way for high-resolution SL system to improve the building accuracy, and the new recoating process can also be applied to current recoating system, so it is important for SL system to improve building accuracy in Z direction with the new recoating method.