DC electromagnetic buzzer: nail stays stuck to electromagnet

[soleiletlune]

hi, i have to build an dc electromagnetic buzzer for school project, but I'm having tons of trouble! can anyone offer advice to help me out? (like good websites with instructions or pointers?) i have most trouble with the connect/disconnect part of the buzzer! i have this nail that is fixed in between an electromagnet and a tin can and everytime it touches the tin can its supposed to complete the circuit, and the electromagnet is supposed to become magnetized and attract the nail towards it which thus disconnects the circuit. this makes the electromagnet become demagnetized again and cause the nail to fall back towards the tin can and complete circuit. this process is supposed to keep repeat, but my nail persistently stays stuck towards the tin can and kind of just vibrates weakly. any ideas on how to make the disconnect/connect more pronounced and fluent?

 

[Unrest]

I think you need to make the magnet stronger.

This might be caused by a poor electrical connection between the nail and the can. You can check that by moving the electromagnet away and seeing if it's just as strong when powered through the nail/can as when it's connected directly to the power supply.

Real buzzers use springs rather than gravity, so they may provide a higher contacting force and less electrical resistance.

It could also be that the magnet is too far away from the nail.

Also consider the flux path for the magnet. Does it easily reconnect in a loop? Using both ends of a horseshoe shaped magnet would be much stronger than one end of a straight one because the flux doesn't have to go so far through air.