Batteries Suck!

I use a magic trackpad. The old one, with batteries you have to replace. Not the new one, you can plug in and recharge. I have to replace my batteries, or recharge them every month and half or so (I’m an iOS developer, I use my trackpad a lot…). Replacing my batteries so often and seeing that ‘Trackpad batteries are low’ alert got annoying.

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The new magic trackpad would solve all my problems, but it’s $129 and I don’t want to spend $129 on a trackpad. After some quick puzzling and a look around the internets, I realized it would be pretty straight forward to make my trackpad wired.

Here’s what I did: I bought a wooden dowel, approximately the diameter of a AA battery. I cut it slightly little less than the length of two AA batteries. Then I screwed one tiny brass screw into each end of the dowel. alt text

I bought a 6’ USB cable and a 5V power adapter (You can plug it into your computer via the USB but I wanted to plug it in via the wall). I cut off the offending end of the USB cable and striped the length plus a couple inches of the dowel rod. alt text

I also stripped the power (red) and ground (black) wires about an inch down. I then wrapped the power around a screw on one end of the dowel and the ground around the other. I put the wired dowel into the trackpad. I put the power end in first to match the direction of the batteries. alt text

Tada! It fits! Don’t be fooled. It took three tries to cut the dowel the correct size… Then I realized I forgot to cut a hole in the cap so I could complete the circuit for the ground wire. Take the dowel out and unwrap the wires.

Next step. Cut a hole in the cap. I used my hand held drill with limited success. Fortunately, I have access to a drill press. Worked like a charm.

Trackpad battery cap

Feed the wires through the hole in the cap, re-wrap the wires around the screws. Put it back in the track pad power end first. Fidget with the cap until you screw it on correctly. Plug in the USB to your computer or 5V power adapter. Press the power button on your trackpad. Does it work? If it does, high five. Otherwise, keep playing with the length of the dowel. Make sure all your connections can be completed.

Note: There are two other wires in the USB cable you don’t need to worry about. Cut them off and wrap their ends in electric tape so they don’t touch or get in the way.