Dụng cụ thắt nút tràng hạt (Rosary Knotting Tool)

This is a tool for making knots on a corded rosary. (It can also be used to make the same knots on other corded bracelets.)

I was able to print it in PLA with no supports and it works great. If you have problems with bed adhesion, adding a brim will help, but it's nice to print without the brim so you don't need to clean it up.

To see how to use this tool, see this YouTube video: 

The tool works well with #9 cord. This is a parametric model in OpenSCAD, so you can tweak the parameters if you need a different cord size.