Arduino Pendulum Clock 4

Fourth Arduino pendulum clock I've built, this time using all the things I learned building previous clocks. This is a true pendulum clock in that the pendulum keeps the time, not the computer. The purpose of the Arduino computer is only to keep the pendulum perpetually swinging,
Description:
The Arduino computer serves the same purpose as the wind up spring in a clock.
The Arduino code is simple and short. easy to code. So far I have this clock accurate to within a few seconds per day.
The clock "movement" is cheap quartz clock which has all the internal electronics removed, it is only used as the gear set to move the hands. The Arduino sends a signal to the clock movement to "tic" (move) the clock hands.
This uses an Arduino Uno with an Arduino screw shield attached, screw shield made building the clock much easier when I needed to remove the Arduino several times during the build, also the screw connections will last longer than the simple Arduino pin connections.
The electromagnetic coil which the pendulum passes over was hand wound.
The clock case is made of mahogany from Honduras.
Leave comments if you have any questions.