electromagnetic - Homemade Electromagnet from Microwave oven transformer

I want to make an electromagnet in order to perform this trick

I have taken the following parts from a microwave oven, and following some instructions i have made the following electromagnet:

I have tried to supply it with power from an 1.5V AA battery then i tried from 4 x 1.5V batteries in serial then i tried from a 12V motorcycle battery and finally i tried from a 12V car battery. None of them gave enough strength to keep down a spoon inside a soup. They did gave some attraction, but it was too weak for what i needed.

Is it safe to plug it directly in 220V / 50Hz AC? Is there another way to increase the strength or it is impossible with this equipment? Is there any safety precautions i need to have in mind?

Answer

a) not safe to plug into mains

b) need more copper wire, fill the available space with turns

c) decide how long you want it to remain attracting for, then aim to heat up your windings in that time, ie use as much input power as you can without overheating. Depending on the cross section of your copper, this may be a car battery, or several in series.

This will allow you to maximise the attraction for that core geometry. It may still not be enough for your spoon.

A steel spoon will be strongly attracted to a magnet. A stainless steel spoon, depending on the precise grade, will be somewhere between very weakly attracted to completely not attracted at all. Make sure you are using the right type of spoon!