Trammel
thingiverse
This is a 3D printed rendition of woodworking trammel that can draw circles up to 5 3/4" (about 140mm). Original wooden version of this can be found here https://www.pinterest.com/pin/229965124709474743/ You would also need a 1/4" by 2" bolt, butterfly nut and a 4d by 1 1/2" common nail Designed in QCad and OpenSCAD
Download Model from thingiverse
With this file you will be able to print Trammel with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Trammel.