It's based off of the String Strecha, utilises leverage to stretch in new strings on any instrument. Showing it here with some Polyurethane U-Bass strings, which are the worst when it comes to needing to settle in.

I am a luthier so any tool that saves me time and makes a process more consistent is good in my books. Maybe it will help someone else out. 

You will need to enable support for this. I used 3 perimeters, and 15% infill. 

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