Efendi, D., A, Y. and K, A. 2018. Comparative Analysis Spindle Speed Constant with Cutting Speed Constant against Surface Roughness Gradual Turning Steel ST 37 on the NC PU 2A Machine. Teknomekanik. 1, 2 (Dec. 2018), 48–52. DOI:https://doi.org/10.24036/tm.v2i1.2272.