Science Buddies: "Ask an Expert"

I wanna make a metal detector by myself, can anybody help me with the theory of its manufacturing.

Hello and welcome to science buddies,
I apologize that no one has responded to your question. The Science Buddies "ask an expert" forum is for helping students in grades K-12 with their science projects. Are you doing a science project that involves a metal detector? If so, it would help the experts here help you if you could describe your project in more detail, including your hypothesis and the experiments you plan to conduct for testing your hypothesis.

Science Buddies has guidelines for science projects which will help you:

https://www.sciencebuddies.org/science- ... ience-fair

Do not hesitate to let us know if you have more questions about your project.