The Hotend is the part of an FDM 3D printer that deals with the melting and deposition of molten plastic material. Therefore a Hotend is composed of a Nozzle that deals with depositing the molten material, a Heatblock that deals with the melting of the material, and a Heatbreak that keeps the hot zone separate from the cold area of the Hotend. The Heatbreak can be equipped with a Heatsink, equipped in turn with a fan.
Hotends come in various shapes and sizes, however common and popular types are the Hotend MK8 and Hotend e3d V6.
The Hotend MK8 are composed of Nozzle, Heatblock, Heatbreak and Heatsink, and provide for the insertion of the PTFE tube in beat with the nozzle. This implies that the PTFE tube is inserted inside the Heatbreak, then the filament flows inside the PTFE tube and reaches the nozzle directly, without intermediate zones.
The PTFE tube, in the part in contact with Nozzle and Heatblock, tends to reach the same melting temperature set for the filament, however this is not a problem as PTFE supports temperatures up to 300 C very well, well beyond the normal printing temperatures of PLA, PETG and ABS. On the other hand, the higher the printing temperature, the greater the amount of heat that the Heatbreak must dissipate; in fact, when the heat is not dissipated properly, it tends to rise inside the PTFE causing the filament to melt in areas far from the Nozzle, resulting in obstructions that prevent the filament from passing. For this reason, it is necessary to accompany the Heatbreak with a heatsink heatsink with fan, in this way the heat passage is quickly interrupted.
The Hotend MK8 is ideal for printing most filaments, however for printing more technical materials it may be unsuitable. In fact, printing filaments that require a high temperature, such as polyamide (nylon), also require a large dissipation capacity; however, the structure of the MK8 Heatsink is not able to dissipate much heat, moreover the PTFE tube present inside the Heatbreak also begins to lose its characteristics, thus causing obstructions.
Hotend e3d V6
The Hotend e3d V6 are composed of Nozzle, Heatblock, Heatbreak and Heatsink, and provide both the insertion of the PTFE tube in batting with the nozzle and the PTFE tube in batting with the Heatbreak. This implies that the PTFE tube is inserted inside the Heatbreak, then the filament flows inside the PTFE tube and reaches the nozzle directly, without intermediate zones, or the PTFE is beaten at the entrance of the Heatbreak and the filament passes through an all-metal area before reaching the nozzle. Therefore, the Hotend e3d V6 provides two different configurations of Heatbreak, or the classic Heatbreak with PTFE or a Fullmetal Heatbreak.
The Hotend e3d V6 has an improved heatsink, with a larger dissipative surface, so it is ideal for printing most filaments, including printing more technical materials. In fact, even the printing of filaments that require a high temperature, such as polyamide (nylon), can be performed thanks to the great dissipation capacity; moreover, if the temperature is excessive for the PTFE tube present inside the Heatbreak, then it is possible to use a Fullmetal Heatbreak that does not suffer from temperature problems.
Unfortunately, due to its large size, it is often very difficult to install a Hotend e3d V6 on smaller printers, for this reason the default installation of a Hotend MK8 is often preferred, which is able to perform almost any printing option for common users with a small footprint.