MagSafe for the Rest of Us: A DIY Magnetic Power Adaptor

Step 2 Build Your Plug

The first thing to do is cut yourself a piece of the copper foil that is just wide enough to cover the metal part of your power adaptors plug. This is to remove any gap between the adaptor plug and the Ring Magnets. I cut my copper sheet width-wise and it was more than long enough.

Wrap this piece around the plug until it is wide enough that the Ring Magnets will fit snugly.

Next, fit your magnets, if there is a space between the plastic of the plug and the back of your magnets you should add a washer so that when it comes time to epoxy them, the epoxy will have more to hold on to.
I used 4x Magcraft brand Ring-Shaped neodymium magnets, size 0.500 x 0.125 x 0.250", Part number NSN0814.  

Push the magnets onto the plug. You may find it easiest to have the copper hanging over the edge of the plug and then to put the magnets over the copper and press the two sides together for a snug fit.

The most important thing is that your magnets have some overhang over the edge of the adaptor, this is so that the Center Power Pin you will make in the next step wont be openly exposed which could lead to a short circuit.

Now cut off any excess copper so that it fits below the edge of the power adaptor.

You are now ready to make your Center Power Pin.