Thor's Not working hammer

Thread Starter

Nelson Gutierrez

Joined Jun 20, 2019
I am trying to do Thor's Electromagnetic Hammer for fun.
But I have problemos.

Here are the battery and resistor amount:

  1. 2 11.1V 3000 mAh Lipo batteries (Running in series)

  2. 68 Ohm Resistor
Here is the wire diagram I am following. Schematic.JPG I followed this diagram exactly with the 3 way connected wires in the right place. When power is running through, the magnet is on even though the key switch is off. When I did turn on the key switched, the resistor burnt up to a crisp. What am I doing wrong?


Joined Apr 11, 2010
You have the “ring switch” in parallel with the relay coil. As such, it doesn’t control the coil and the relay will always be on. It should be in series with one of the coil leads. Either one, it doesn’t make a difference.

As for the resistor burning up. With the switch open, voltage passes through the relay coil and then the resistor. The coil drops some of the voltage and limits the current. But when you press the switch, the current bypasses the coil and all of it flows through the resistor. Too much in fact and the resistor burns up.


Joined Sep 17, 2013
What are the voltage/current/power/resistance ratings of the relay coil? That info will enable the resistor value to be calculated.