High Temperature Filament Dryer

Attention, due to the high voltage and temperature, this model is not intended for assembly by beginners! Think 10 times before you start making it. I am not responsible for your actions and the consequences! To manufacture this dryer, you will need access to a laser cutting and bending service for sheet metal. The necessary files for obtaining unfolded drawings in dfx format, as well as information on the fold lines, are attached to the project. The case is made of steel, which is then coated with powder paint. The internal thermal insulation is made of high-temperature foam rubber with an adhesive layer. The top removable cover and filament spool rollers is made of PP-FG or other heat-resistant plastic. The top cover consists of a panel and two prismatic air guides screwed to it. Thermal fused brass nuts are used for fastening. This makes printing easier and provides some variation. Additional rollers tubes for the filament coil fitted to the bearings may not be installed. These rollers make it much easier to fit the sides of the coil into the appropriate slots. After painting the panels, the M4 thread will need to be cut into all holes with a tap, with the exception of the holes for AC-DC power supply holder and the power inlet socket, for which the M3 thread is used. To cut insulation sheets, you can make a template based on their 3D model. I recommend pre-assembling only the metal parts of the case, and if everything is fine, then apply the thermal insulation sheets and make the final assembly. As a heater used a widely available on Aliexpress 350-400W PTC heater module with a built-in fan. Unfortunately, a standard 24V DC fan overheated at a certain temperature and stopped rotating. This is a very dangerous situation that could theoretically cause a fire! Therefore, I replaced the low-voltage standard fan with a high-temperature 230V AC fan, which I recommend to you. I also made a spacer out of PA6-GF to separate the fan housing from the heater. After that, I didn't see any more problems with the temperature set at 100 degrees on the thermostat. So, I see no point in making holder and installing a 24V AC-DC power supply to power a low-voltage fan. This will not only increase reliability, but also reduce manufacturing costs. The widely used W3230 thermostat is used to maintain the temperature. Thanks to the step files, you can redesign the front panel for a different thermostat model. A thermostat with a PID controller would be preferable, but they tend to have larger overall dimensions and, it seems to me, are more critical to heating their electronic parts. The temperature sensor is installed in the output channel to prevent overheating. Do not forget to calibrate the thermostat readings on the high temperature test filament spool using a suitable external thermometer! This will allow you to determine the temperature deviation range and make the necessary correction. Otherwise, overheating of the plastic is inevitable. You will also need to determine the maximum operating temperature based on the materials used. The components are connected to each other according to the documentation provided by the manufacturer. I used a temperature-resistant silicone tube to lay the wires. A 2A fuse must be installed in the fuse holder of the power inlet socket, which, for a 230 V supply voltage, will give a maximum power of over 400 watts. I would also recommend installing a protective thermal relay screwed to the metal part of the housing. Due to the relative complexity and danger of the project, I am not ready to give explanations on the design and other advice. I repeat, this project is designed for those who can figure everything out on their own.