This a working 12 hour clock I made using events. I have never seen someone else make a working clock in blockland so I thought I would give it a try. The controls to set the time are inside, along with start, stop, and reset buttons. *Note: if you manually set the hour timer above 12 hours it gets messed up so you need to press the hour reset button if you do. Other then this there are no other bugs I know of.
You can also have many other clocks at once that base their time off the main one by naming print bricks in this order (from left to right) hours, hour, minutes, minute, seconds, second. It is also possible to load this into other maps and rotate and move it with the duplicator tool because it handles directional relay events when bricks are rotated so there are no errors when doing so.
*edit: the timescale of the server will effect the clock, and it does not synchronize its time to your computers clock, you have to do that manually.