Precision Circle Cutter

thingiverse

Circle cutter for paper, cardboard or other thin materials without center tip. Also useful for marking a circle on harder, thicker materials. An Imperial version is available! Cutting is done with a fresh segment of an utility knife blade. The reticle in the base can be viewed from three different angles - from the sides and from the top. This makes aiming at the center quite easy and precise. No center pin is needed, which avoids unwanted punctures in the work piece. The base simply presses down onto the material. A circular groove in the bottom allows a piece of flexible filament (1.75mm) to be used for anti-slip purposes. This works great and enables the use of an quite long arm. The blade holder can be mirrored to mount the blade between the holder and the base, as shown in the images with the all-white background. This sacrifices 15mm of the radius but makes it safer to use. In this configuration, the edge can also be placed in the big hole in the base for storage, where it is covered quite safely.