Caliper for steel rule
thingiverse
This gadget may not be a high-precision caliper, but it's incredibly useful for measuring objects. To create one, you'll need four Neodymium round magnets that measure 9mm by 1.5mm. It's designed to work with standard steel rules, however, you can easily adjust the thickness between the rule and the tool to suit your needs.
Download Model from thingiverse
With this file you will be able to print Caliper for steel rule 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 Caliper for steel rule.