Lathing process is a process of formation of components and equipment such as solid shaft, hollow shaft, a threaded shaft, and other forms of action cutting.The aim of this study was to analyze the differences between the cutting time cutting time theory and practice in the process of turning. Techniques used in analyzing data is a time difference of cutting (cutting time) the results of experiments using statistical methods. Data processing using the distribution of student "t" by taking a significance level a = 0.05 (1-t) = 95%. From experimental cuts to the depth of cut thin (taken 1 mm), that the result of calculation of cutting time 69.4 seconds. While the practice of cutting time (trial) was 71 125 seconds, or difference 2:39%. For a depth of cut thick (taken 4 mm), the cutting time result of calculation of 42.6 seconds and the cutting time is 43.45 seconds or practice the difference is 1.96%. The result of the calculation of the distribution of student "t" in the amount of 26.87 seconds and 23.78 is much larger than t (0.95) of 1.71. Thus the hypothesis which states that the practice of cutting time longer than the cutting time can theoretically be accepted as true.