Angle Gauge set
By erikcederb
Free
It's free to download
Videos
Images
Documentation
Information
Angle Gauge set
By erikcederb
Print flat on print bed, you might want to look into the Cura setting "Initital layer horizontal expansion" with a negative value to combat elephant foot, since you need precise sides.
The holes can be used to put a wire through to keep them as a set.
Free