Glow in the Dark Wall Clock (Lidl Livarno)

To be able to see my wall clock's time hands at night I bought some luminescent paint from Aliexpress - the traditional copper-doped zinc sulfide kind, not the strontium aluminate type. It's just bright enough to tell the time if you have good night vision.

The hands are difficult to paint without removing them, and removing the hands is quite difficult - and risks damaging the clock in the process. Clockmakers like to use a clock hand puller tool (which relies on the center pin, a part that isn't very strong in this clock), DIY pry bars, (top) cutting pliers, scissors, etc.

The paint will add weight to the hands, causing the stepper motors to work harder and drain the battery faster.

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After prying off the rim and removing the glass plate, I tried to pull off the second hand. However, I had to use so much force that I was afraid it might snap, so I decided to brush the paint on without removing the hands.

The paint turned out to be too thick to apply cleanly (forming strands and blobs) so I thinned it with some water. Unfortunately, the diluted paint ran down the hour hand and in between the gear shafts of both clock hands gluing them together. The paint is water-based, dries quickly, and sticks on like a strong glue.

Left with no other options, I pulled off the second hand with a lot of force, followed by the hour hand, which left its brass holder behind on the shaft. This holder has a narrow section onto which the minute hand is press-fitted, and a slightly wider section facing downward toward the minute hand.

Pulling it off buckled the back plate, but eventually it did give way, allowing me to remove the hour hand as well. The hands appear to be made of sheet metal, and the minute hand has a crimped holder that is integral to the sheet metal itself, unlike the separate brass fitting used for the hour hand.

1. Fluorescent Paint (I chose one of the three white/translucent colored bottles listed as color 01).
2. Mobile Phone (Curved) Spudger
3. Heat-Gun
4. Vise

1. Press and hold reset for 4 seconds (or remove the battery and put it back in). The hands move to the 12:00:00-o‘clock position and stop.
2. Remove the battery with all hands still pointing to the 12:00:00-o‘clock position.
3. With a spudger move around the base of the clock until the aluminum rim comes loose and can be removed.
4. Pull off the second hand.
5. Pull off the hour hand if possible together with its holder.
6. Pull off the minute hand.

DIY clock hand removal video's

How to make watch hand removers - @bunnspecial

Removing a clock mechanism and hands - @dianaflintoff4192

Taking clock hands off with tools laying around your house - @munnerlyn3

1. If the paint is like pudding, stir in a small amount of water.
2. Spread it out over the hands. I put on thick watery dome-like layers held in place by surface tension.
3. Dry with a heat gun.
4. Apply next layer.
5. Test with UV light until satisfactory result.

Apply the same amount of paint and layers to both hands so they both glow equally bright.

1. With the clock mechanism still at the 12:00:00-o‘clock position push the hour hand back onto its shaft (lightly if you want to test the result first).
2. If necessary press fit the minute hand back onto its brass holder. Then push both back onto the minute shaft.
3. Press the second hand back onto its pin.
4. Put the glass and the rim back in place.

You may want to lightly fit the hour and minute hands first to test if the result is to your liking or whether more paint is required to improve visibility. I can read the clock clearly at night from three meters away without using UV or any extra light to charge the hands.

Some pictures to show the internals and how to reassemble them. Several cogs have an embossed number on them. The mechanism has a ferrite coil antenna, two Lavet-type stepping motors, two crystals, a side-viewing IR-emitter (designated JS-JS on the board), paired with its receiving photo diode (D1) to track clock hand position. Some cogs are see-through and solid, while others are black and have a unique pattern of cutouts and holes allowing identification and tracking (optical rotary encoders).

Note: I placed the antenna with its coil right above a crystal oscillator, although it may have been on the other side originally.