Nowadays, the desktop 3D printers are common in computer aided manufacturing and widely used in multiple applications across homes, offices, and in several business sectors, etc. A wide variety of filaments like PLA, ABS, PETG, TPU, etc. are now being used in Fused Deposition Modeling (FDM). These filaments require different temperatures to print. FDM is a process in which a material in its filament form is melted and deposited layer by layer to form the required object. The hot end of a printer plays a crucial role in the melting of these filaments for printing. It is a major component of a 3D printer, where the filament is brought to a semi-solid state, to extrude and deposit the filament in layers. In this research study, the hot end of "Ender 3" and "CR-10S Pro" are modeled using Computer Aided Designing software, and thermal analysis using Finite Element Analysis, is carried out by applying the maximum printing temperature of PLA for the two printer hot ends. To optimize the problem of wide temperature gradient which often results in clogs and jams across the hot end, the design of heat sink is modified to maximize heat dissipation. Alongside, the simulation result is also compared with manual experimental readings.