This kit will allow you to build a superb doorbell for the door of your room. You will discover, by building it, gear trains and basic mechanical principles such as friction effect. You will manipulate a lot of materials: nuts, screws, washer, joins, tightening rings, and even a hair elastic. Each step of the assembly explained through the brochure.

You will discover that there are a lot of kinds of gears and they are very present in the objects that surround us.

What will you learn?
- The different types of gears: gear trains, rack, pinion, circular, etc.
- the ratios to calculate the speed at which the gears are turning
- the effect of friction, the crank

Each kit contains a brochure illustrated in 5 languages:
- A step-by step with very clear explanations and great illustrations
- Pedagogical content on the theme
- Languages: English, French, Spanish, German, Dutch.

Product measures 27 cm x 18 cm x 5 cm.