All necessary spare parts can be selected from unnecessary things. What we need: an iron lid from Coca-Cola, a miniature electric motor, a battery , a rod from a ballpoint pen and a switch.
We fasten the battery, the switch and the electric motor with the help of hot melt adhesive and a pair of wooden sticks. Next, straighten the iron cover with a hammer and cut out the “teeth” on it. The resulting cutting disc is inserted on a piece of the rod and attached to the axis of the motor. Everything is mini dremel ready.
More detailed instructions can be seen in the video.