Penelitian ini dilaksanakan untuk mengetahui pengaruh posisi objek dalam pembuatan protipe cepat (rapid prototyping) dengan menggunakan 3D printing untuk bahan polymer PLA dan ABS terhadap kekuatan tarik maupun ketelitian dimensi yang dihasilkan. Untuk  mencapai objektif penelitian ini dilakukan percobaan dengan membuat prototype spesimen ujitarik berdasarkan ASTM dengan menggunakan 3D printer. Produk yang dihasilkan dilakukan pengukuran dimensi untuk melihat akurasi peroduk melalui perubahan dua posisi variasi orientasi objek yakni secara vertikal dan horizontal. Setelah proses pengukuran dimensi, dilakukan pengujian tarik spesimen dengan menggunakan alat uji tarik. Dari eksperimen yang dilakukan diketahui bahwa posisi orientasi dan besar layer pada proses printing memberi efek terhadap kualitas permukaan, efisiensi waktu dan kekuatan dari benda. Produk material PLA dengan orientasi posisi objek horizontal memiliki kualitas dimensi yang paling baik. Jumlah kesalahan akurasi material ini tidak melebihi 1 mm pada setiap layer. Material ABS dengan posisi orientasi objek  vertikal dan tebal layer sebesar 0,10 mm menghasilkan kekuatan tegangan tarik yang terkecil sebesar 8,62 MPa dan material PLA dengan orientasi posisi objek horizontal dengan dan tebal layer sebesar 0,40 mm menghasilkan kekuatan tegangan tarik terbesar 35,57 MPa

In the machining process, increased production can be done by increasing the use of cuttingparameters. However, the use of high cutting parameters has an effect on the wear of the cutting toolused. The aim of this research is to analyze the wear and tear that occurs on cutting tools and tool lifewhen cutting AISI 4140 steel by using variations in cutting speed. The machining process uses a CNClathe by turning the surface of the AISI 4140 steel workpiece. The wear criteria are determined when thecutting tool has reached the edge wear limit (VB) of 0.3 mm. Observation and measurement of carbidecutting tools are carried out every 5 minutes the machining process is carried out. If the cutting tool hasnot shown the specified wear value, then the cutting tool then cuts, so that the wear value is obtained.From the research conducted it was found that at a cutting speed of 160 m / min the cutting tool iscapable of cutting for 39 minutes, 13 seconds. At a cutting speed of 180 m / min the cutting tool is capableof cutting for 38 minutes, 14 seconds. At a cutting speed of 200 m / min the cutting tool is capable ofcutting for 33 minutes, 8 seconds. At a cutting speed of 240 m / min the cutting tool is capable of cuttingfor 26 minutes, 3 seconds. Taylor's advanced tool life for the coated carbide cutting tool in turning AISI4140 steel material is: Vc. Tl.0.073 = 8203.

In manufacturing industries specifically in metal machining, the use of the cutting tool is important to consider. The use of the cutting tool has not been used optimally, as well as cutting parameters. In the cutting process, the wear of the cutting tool and cutting force has a very close relationship. This research was carried out to analyze the wear of coated carbide cutting tool and cutting forces produced in turning AISI 4140 steel workpieces. This study was conducted with a variation of five cutting speed levels consisting of 180 m/min, 220 m/min, 260 m/min, 300 m/min, 340 m/min and depth of cut 0.7 mm. To observe the tool wear, every 5 minutes with a maximum limit value of VB of 0.3 mm and for the cutting force values taken every 1 minute. From the results of the study obtained: The increase in the value of the cutting force is affected by the increase in wear that occurs in the cutting tool due to a change in tool geometry due to wear on the cutting tool. The highest feeding force value is at the cutting speed (Vc) 340 m / min at 368 N and the greatest cutting force value is at the cutting speed (Vc) 340 m / min at 371 N.

In the machining of metal cutting, cutting tools are the main things that must be considered. Using improper cutting parameters can cause damage to the cutting tool. The damage is Built-Up Edge (BUE). The situation is undesirable in the metal cutting process because it can interfere with machining, and the surface roughness value of the workpiece becomes higher. This study aimed to determine the effect of cutting speed on BUE that occurred and the cutting strength caused. Five cutting speed variants are used. Observation of the BUE process is done visually, whereas to determine the size of BUE using a digital microscope. If a cutting tool occurs BUE, then the cutting process is stopped, and measurements are made. This study uses variations in cutting speed consisting of cutting speed 141, 142, 148, 157, 163, and 169 m/min, and depth of cut 0.4 mm. From the results of the study were obtained that the biggest feeding force is at cutting speed 141 m/min at 347 N, and the largest cutting force value is 239 N with the dimension of BUE length: 1.56 mm, width: 1.35 mm, high: 0.56mm.

The development of mechanical and physical properties of metal materials is so fast, that it requires cutting tools that are capable of cutting the metal.Cutting tools must have high temperature resistance, high wear and hardness. Ceramic cutting tools have these properties, so they are suitable for use in cutting hard metals. In the metal machining process, especially machining of cast iron which has high hardness and strength, has a strong reason to use the ceramic cutting tool.This research was conducted to determine wear on ceramic cutting tools when cutting cast iron.The study was carried out experimentally using a Mazak CNC lathe.When the turning process is done, the cutting tool cuts the metal cast iron. Every 10 minutes, the turning process is stopped to observe and measure the wear that occurs on the ceramic cutting tool. Observations and measurements are carried out using a digital microscope.The wear criteria are determined if the tool edge (VB) has been worn at 0.3 mm.The results showed that wear at the cutting speed of 200 m / min at 60 minutes is an adhesion process. BUE (Build Up Edge) wear is a buildup of material layers in the chip area near the cutting tool.