Combining the two of my newest hobbies; lockpicking and 3D modeling I thus present a simple pin tumbler lock model with a cut on the side for viewing / demonstrating the operation.
This is just for demonstrating the operation and there is no latch in the end of the plug for actually connecting it to something or w/e. It can be picked, although I recommend using very light tension due to thin chamber sides on the open cut area. Also due to layers, all the pins act bit like serrated security pins unless you smooth them. :)
I printed the plug and the housing from PLA with 0.2mm layer height, 10% infill and 2 perimeters and using slic3r automatic supports. Driver pins and key pins are best to be printed with thinner layers (0.1mm).
Springs I took from ballpoint pens, cut one spring in half to get correct height springs for 2 chambers.
No key provided, arrange the key pins however you like and make your own :)
UPDATE: Added block_cut_v1.1 and cylinder_cut_v1.1 which feature slightly thicker walls for the chambers in the cut area, that should improve the strength of the chamber walls and make printing easier.
Recommend using support for housing and the plug, depending on your printer you may/may not be able to print them without support too.
Use small layer height for pins.
Print 5 x driver pins and 5 x key pins (different heights provided).
Ballpoint pen springs for driving the pins.