This study examined the effect of sonication on FTIR and stability at various temperatures in water-based lubricants with a mixture of Carboxymethyl Cellulose (1wt%) and Uncaria Gambir extract (1wt% and 2wt%). The sample was prepared by mixing the two materials into distilled water using a magnetic stirrer and sonicator with time variations of 5 and 10 minutes. Before mixing, the Uncaria Gambir extract solution with water is first centrifuged to remove the dregs in the Uncaria Gambir extract powder. Stability was carried out in an open room (28oC), drying oven (50oC), and refrigerator (5oC). The stability test results showed that the mixture of Carboxymethyl Cellulose and Uncaria Gambir had good stability at all temperatures after sonication for a short duration. The longer sonication duration could fuse the fibrils of Carboxymethyl Cellulose, leading to increasing particle size. FTIR results also show that there is no chemical reaction that occurs. After adding the gambier, there was a new peak at wave 800-1300 cm-1, corresponding to the gambier. The results of this study indicate that the Carboxymethyl Cellulose and Uncaria Gambir solution can be a potential lubricant additive. The Carboxymethyl Cellulose can be a viscosity modifier, while Uncaria Gambir extract for corrosion inhibitor.

The surface quality of turning can be influenced by several factors such as determining the spindle rotation speed, determining cutting speed (cutting speed), cut angle. the purpose of this study was to compare the level of surface roughness in the mild steel ST 37 on lathe process. Every surface of the workpiece that undergoes a machining process will experience varying degrees of roughness. This research is an experimental study that compares the level of surface roughness of material material Mild Steel ST 37. Material that is done with a length of 70 mm, and turned into a diameter of 20 mm using 3 kinds of cutting angles and 3 kinds of spindle rotation speed. Measuring the surface roughness of the workpiece, namely surface tester mitutoyo SJ-201P. The results of this study can be concluded that the spindle rotation speed of 740 rpm with 80˚ cutting angle produces a smoother surface that is (∑Rap) = 5.76 μm or in the roughness class N9 while the spindle rotation speed is 440 rpm with 80 potong cutting angle produces a surface coarse (∑Rap) = 11.47 μm with N10 surface roughness class.

The author observes that the use of belt grinding is still rare in the writer's own environment, both in the fields of education and small industries, because there are still many people who are fixated on ordinary grinders, and think that ordinary grinders are better in all work. The development of belt grinders has changed people's perspectives through the development that the authors have done, with increasing belt grinding functions through development which will certainly make belt grinders even more useful. This belt burrs are made and developed through pre-existing belt grinding shapes. The result of this development is a belt grinder which has a function more than the belt grinder which is already before. This belt burrs has three types of work functions, namely vertical, horizontal, and cutter, and also features speed control. With the development that the author does, of course, it will change people's perspectives because belt grinding has a function that is better than before and can better help the work of a grinding process.

Kekasaran permukaan dari proses pembubutan dipengaruhi oleh berbagai faktor diantaranya adalah kecepatan spindel dan sudut potong yang digunakan. Setiap benda kerja yang dikerjakan pada mesin perkakas tentu menghasilkan kekasaran permukaan yang berbeda. Penelitian ini bertujuan untuk mengetahui pengaruh sudut potong kecepatan spindel terhadap kekasaran permukaan baja karbon EMS-45. Metode Eksperimen lebih cocok digunakan pada penelitian ini agar  mengetahui pengaruh sudut potong dan putaran spindel terhadap kekasaran baja karbon EMS-45. Bahan yang digunakan berdiameter 25 mm dan panjang 90 mm, dengan kedalaman pemakanan sebesar 0,2 mm dengan 3 jenis sudut potong yaitu sudut 60º, 75º, dan 90º sedangkan putaran spindel yang digunakan yaitu 995 rpm, 1267 rpm dan 1459 rpm. Kekasaran permukaan diukur menggunakan surface rooughness tester. Hasil penelitian didapatkan nilai kekasaran permukaan terendah  pada pengujian spesimen dengan spindel speed 1459 rpm dan sudut potong 90º yaitu 1,58 µm sedangkan kekasaran permukaan tertinggi diperoleh pada kecepatan spindel 995  rpm dengan dengan sudut potong 60º yaitu 2,39 1,58 µm. Kesimpulan dari penelitian ini adalah sudut potong dan kecepatan spindel berpengaruh terhadap nilai kekasaran permukaan dimana semakin kecil sudut potong maka semakin kasar permukaan yang didapatkan dan semakin besar putaran spindel maka kekasaran yang didaptkan semakin kecil. Kecepatan spindel 1459 rpm dengan sudut pemotongan pahat sebesar 90˚ menghasilkan permukaan yang paling rendah yaitu Ra = 1,58 μm dengan tingkat kekasaran permukaan berada di N6 sedangkan kekasaran permukaan paling tinggi dihasilkan pada kecepatan spindel 995 rpm dengan sudut potong 60˚ yaitu 2,39 μm dengan tingkat kekasaran permukaan berada di N7.

This research aims to analysis comparative feeding variation to quality surface processes blocking equipment of ems steel 45on cnc latheing machine. Quality products are obtained from good cutting conditions. One of the most important variable cutting conditions to obtain surface roughness quality is feeding. The purpose of this study was to see the comparison of feeding variations of G94 and G95. The multilevel cutting process is carried out with a cutting depth of 0.5 mm and a length of 40 mm with a carbide cutter with feeding variations (G94 / G95) of 0.3048 mm / min and 0.3281 mm / min respectively and at the price of the round / cutting speed speed (G97 / G96) is controlled. Surface roughness testing using Surface Tester Mitutoyo SJ-201P. The result of this research can be concluded that the higher the surface roughness obtained is lower compared to the average price of roughness of the lathe result that uses low feed.