Mechanical combination safe lock (hand changeable combination)

Assembly video: 

This requires a decently tuned printer. Press fit parts that are not supposed to move have 0.1mm of clearance and parts that are supposed to fit and still rotate without being loose have 0.2mm tolerance. No supports, gluing, or anything other than 3D printed parts are needed!

File names include how many of each to print. To assemble, put each inner wheel inside each outer wheel. WheelInner1 will be wheel 1 and the other two wheels with WheelInner23 will be wheels 2 and 3. This should be a tight fit! Put parts on the mount in this order:

Wheel1

Spacer

Wheel2

Spacer

Wheel3

Spacer

Drivecam

Then insert the dial, line up the hole on the end with the drive cam, and push the spline key in (long end first). This has to be a tight fit! Then you can insert the bolt, and the lever into the bolt, then the spring. Wheels should spin smoothly but not loosely on the post, sand the inside of the wheels if they are too tight. 

If printing the full safe box version, simply print Door instead of Mount then also print the files in the Safe Box folder (Box, Hinge, Handle, and HandleNut). 

To get the numbers on the dial I just added text using my slicer and exported it to the file DialWithNumbers. You can use this for dual color or simpy cutting the numbers from the dial. If you choose not to go with this option I highly recommend taping/gluing a piece of paper with markings around the dial to get more accurate readings.

To change the combination just pop out the inner wheels and put them back with a different rotation.