Add more functions to 3d printers is a topic in my recent project. I have added a multi-pen plotter that can print color images easily. Now I try to add a drag knife to it. I have no experience so I first try the commercial one to learn how the knife works with my own eye.
The adjusted screw can adjust the force of the spring. I use a spring from a ballpoint pen this time. It is quite soft. But since the linear motion bearing is not smooth as I expected, the result is not good. Some reason I already know. Mostly it is caused by the linear motion ball bearing is not smooth enough since I chose a cheap one to test. I will make some modifications to get better results.
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