DIY USB LED Light: Switch & Magnet Upgrade

If you're interested in modifying a USB mini light, this article is for you.

In our previous DIY post, DIY USB LED Light: Teardown & Assembly Guide, we explored the disassembly and reassembly of the USB light, focusing on its structure and materials. This time, we're taking it a step further—modifying the light with a magnetic switch housing. If that sounds like something you'd enjoy, keep reading.

To start, try adding magnetic mounts.

Use the magnetic nuts that came with the LED board and attach them to the back of the light—one on each side.

However, these magnets stick out quite a bit, which doesn't look great. A better approach is to extract the magnetic discs themselves and stick them directly onto the back of the light. This lowers the overall profile, though they'll still be slightly raised above the surface.

If that still feels too bulky, you can heat the discs into the plastic using a soldering iron.

Keep in mind that these strong magnets are made from neodymium, which loses magnetism at high temperatures (typically anything above 150°C). So, it's best to insert them from the back rather than heating the front directly.

Once inserted, clean up the slots you made so they're flush and neat—this will help secure the magnets properly.

Note: If a magnet has been exposed to high heat, it may already be demagnetized.

After prepping both sides, you can glue the magnets into place using 502 adhesive (a type of strong superglue).

Next, let's add a switch. You can use a simple flashlight switch.

Solder it in place, and reassemble the shell. 

Originally, the light wasn't fastened with plastic rivets—just heat-melted plastic at the screw points. If you want to avoid using screws, you can place a small piece of paper over the joint and heat it lightly to melt the plastic for a cleaner bond.

This method also keeps your soldering iron tip clean and the final appearance neater.

Once the switch is installed, dab a bit of thermal grease on it.

Press the housing together to help mark where to drill the hole for the switch—this makes alignment much easier.

Here's what the modified light looks like after everything's done.

And here it is lit up with power connected.

If there's enough space inside the shell, you could try adding a POS terminal battery—but keep in mind the capacity is quite limited, so it's not highly recommended.

All done.