This padlock is fully 3d printable! It is a simple tumbler lock.
All parts are in the correct orientation. The pin.stl file is optional, but it makes it so the padlock can't be cheated by gravity.
The key.stl file must be printed with support. All other files should be printed as-is. Recommended 0.2mm layer height or finer. Print the bolt with 100% infill for best strength. I suggest gluing the tabs of the cap in place for best security, though it should snap in place and stay there firmly. If it doesn't snap in, you can scale to 95% size and see if it fits better.
If you have any questions about the file, how to print it, how it works, or anything else, please send me a message.
This model has been tested. I printed it on my creality cr-10 with 0.2mm layer height, and it works.