I created this template to help me glue replacement Roman numerals on a cuckoo clock dial that had lost its numbers.
Each edge of the 12-sided figure provides a base line for you to up-down align each numeral to. Each line through the center of the figure provides a center line for you to left-right align each numeral to.
Watch my demonstration YouTube video to see how to use the template. My blog post describing the whole process, including how to buy Roman numerals, is at https://needhamia.com/replacing-the-numbers-on-a-cuckoo-clock-dial/
guidefor70mmDial.stl is the template for a 70 mm cuckoo clock dial.
guidefor80mmDial.stl is the template for an 80 mm dial.
Print with the grooves face down on the print bed, and the center post pointing up. I used the default Slic3r PE settings and PLA.
It's ready to use, right off the printer. Push the post through the front of the clock dial, then turn the template to line up to any existing numbers on the dial.
If the template turns too easily, align the template then put a strip of Scotch tape (transparent tape) or masking tape across the back of the dial, and press the center of that tape strip into the post of the template. That should hold the template in place long enough for you to glue the numerals on the dial. Of course, remove the tape and template when you're done.
My demonstration video (see the link above) notes explain what glue and tools you need.
guidefor70mmDial.f3d is the Fusion 360 design file for a 70 mm dial template.
guidefor80mmDial.f3d is the file for an 80 mm dial template.
The file has two User Parameters (under Modify / Change Parameters) that you'll want to change for a different sized dial:
postDiameter is the diameter of the central post of the template. You should make this about 0.5 mm smaller than the inside diameter of the central hole in the dial.
baselineToBaseLine is the distance (diameter) from the base line of one numeral to the base line of the numeral opposite it on the dial. For example, XII is opposite VI on the dial.