Integrated Hinge
thingiverse
There are many stand-alone hinges on the web, but this is one that can be included in your print projects as something integral in your parts. The hinge itself is not meant to be printed out on its own. Rather, where you have two parts that are to be hinged together, just merge a copy of the hinge onto each part, and print out the pin to finish the job. When adding to your project, the edge of the rail under the openings should be flush with the edge of the part, and the top of the platform should be flush with the top of the part. If the part in question doesn't have a neat 90-degree angle to work with, feel free to edit the platform as needed, either before or after merging it with your surface. I'll add more versions of the hinge and/or the pin as the need becomes apparent (requests and suggestions are welcome). UPDATE (13 Oct 21): I added a 2mm version to the 5mm version already up.
With this file you will be able to print Integrated Hinge 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 Integrated Hinge.