Idea and First Tests

First I started with scratching, matt varnish and white paint on the ball. This didn´t meet my expectations at all.
After some playing around with the clear ball and the LEDs, I figured out that the reflections on the inside of the ball worked best for me.

Another thing is the voltage for the LEDs. Blue LEDs need a higher voltage then red, yellow or green ones. The LEDs I chose needed about 4 volts. The batteries I always use for these projects have 3 volts, so I put two in a serial circuit which gives me 6 volts. Unfortunately, that´s a bit too much. A resistor of 130 ohms for each LED solves the problem for me.
Time to bring it to life.

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