Round Corner Radius Stencil / Template - Imperial & Metric

2026-04-25 UPDATE:     I redesigned these so that they fit together in a nested arrangement on a pegboard hook. This makes the sets more compact and orderly, and fit on a shorter hook, or allow both sets to fit on the same short hook. See attached photos. I had been wanting to make this redesign for quite a while, but just didn't get around to it. I used the original non-nested versions yesterday, and it was bothersome how they didn't fit together nicely on the hook. So, I finally fixed them. :D For simplicity and to avoid confusion, I have deleted the old/original designs; however, I am keeping some of the original graphics.

- - - - -

These are templates for marking or scribing rounded corners, in inch/Imperial or Metric sizes. These are designed to work with mechanical pencils and ultra fine markers. The templates have 1/16" channels to negate some inaccuracies caused by rough corner edges. Each of the four templates uses about 15-16 grams of filament.

The Inch/Imperial templates are in 1/4 or .25 inch increments, from .25" to 4", making 16 available arcs, if you print all four of the templates.

The Metric templates are in 5 mm increments, from 5 to 100 mm, making 20 available arcs, if you print all five of the templates.

The templates have hanging hook holes for pegboard hooks, nails, etc. They are easy to use. Print them face down and at a finer resolution (.12mm - .16mm) for better quality. Print initial 2 layers at slow speed for improved accuracy. No supports are necessary.

When using the templates, hold your pen or marker against the inside edge of the rounded slots.

NOTE: Concave corner stencils/templates are also available at:

This design was inspired by drphysics' design: https://www.thingiverse.com/thing:4752918 . However, I wanted to make templates with a wider range of corner measurements.