Log cabin transfer scribe

This tool is not used directly for measurement, but it helps to accurately transfer the curvature from one object to another

I was always fascinated when I watched the log building series by the masters of Pioneer Log Homes of British Columbia. I was very interested in how exactly they cut the holes for the saddle notch, they used such a scriber for that. 

I am interested in various hand tools. So I tried to create such a tool.
Such a tool costs hundreds of euros, if you want quality, buy it, but maybe this one would help home hobbyists.

The description of the assembly and the necessary material is in the photo.
Use 3 perimeters for the print settings and 6 perimeters for the arms to keep them firm

I like to work with wood, several years ago I created similar log cabins, but miniatures