Chinese wellzoom desktop extruder making PET filament.

This cheap extruder can make quite a good quality of 3d printer filament. I tried PET and PLA with the little guy. PLA is easier to handle with. The only drawback is it's speed, 1kg filament (1,75mm) in 5-6 hour. The performance is only 150W, so it is acceptable. The winder is my own creation. :) It is ticking because it has to turn a bit faster than a filament comes in order to strain it and the torque is limited through the current level on the stepper motor driver. Thus the stepper fail much steps and the ticking effect appears. It sounds funny but it does his job well. My advice The key for stable filament diameter and good quality: pull down the material from the extruder. It is very important. For example: Use 2mm extruder nozzle, and pull down the extruded material to 1.75 mm with the stepper motor. You can easily adjust the speed of the stepper with a square wave generator. I have created one from a good old arduino Uno, you can see it in the video with the blue lcd. Good luck! Here is the code and the printed parts: https://drive.google.com/drive/folders/1PoPX-7NuaXHOpLDb_ax1WC93fmxsdgnQ?usp=sharing