It’s remarkably easy to hack LEDs into Lego minifigures to make awesome, creepy, and tiny decorations for Halloween.





In what seems like a miraculous coincidence, a standard LED fits exactly into the head of a Lego minifigure. It’s that easy: grab an LED and a head, slip it in, and it fits perfectly.

The modern Lego minifigure dates to 1975-8. Since LEDs were already coming in 5 mm packages (also called T 1 3/4 packages) by the mid 1970’s, it’s clear that Lego minifigures were made to fit LEDs in their heads. It’s a sign from above: The little yellow guys are simply meant to have light-up noggins. Who are we to argue with fate?

It’s a good idea to carve your head before putting the LED in. (No, not your head, the head of your Lego minifigure.) This is particularly important if you’re starting with an older Lego head, since the suction can make it hard to remove the LED. (Newer Lego minifigure heads have a vent in the top.)

If necessary, wipe the smile (and eyes) off of its face with some rubbing alcohol. To carve the face, use a hobby knife with a sharp blade. You will be tempted to work with the knife very close to your face, so that you can see what you’re doing. That’s fine, but it’s a very good idea to wear some eye protection. Once you’re done carving, use the knife to remove any burrs or chips on the inside, which could make it difficult to insert the LED.

In order to mount the modified head on the body, you’ll need to cut off the neck and widen the hole to accept the base of the LED. I actually trimmed the bottom of the LED down a bit so that I didn’t have to make the hole quite so big. In any case, carving the body is quick and straightforward with the knife. I didn’t have any batteries small enough to fit inside the body itself, so I also cut a little hole in the back to let the leads out.

To assemble the figure, take the legs off, put the LED in the head, put the head on the body, bend the leads out the back, and reattach the legs. This works well because once it’s assembled, you can’t see the leads from the front.

Here’s the completed figure: It needs a caption! Please leave your suggestions as comments or on its flickr page!

The figure stands on its own. The leads of the LED stick out the back, where they lightly touch the sides of a lithium coin cell.

The pumpkin head took several hours to carve. The next day I had blisters on my thumb and index finger where I had been holding this little head (tight) while I carved.

While it is often difficult to get this level of detail in something so tiny, the hardest part in this particular case was making the three initial holes through the thick plastic. If I had to make this one over again, I would start by drilling three tiny holes in the head.

I put a red-orange LED in the head and attached it to a lithium coin cell to try it out. It looks a little bit like an LED throwie, but I guess that it’s really a

“Lego throwie.”

The pumpkin head was attached to this minifigure body, which was modified in the same way as the other body. The Lego horse provides a platform to rest the lithium battery, and the cape covers it all up. The things fit together nicely on their own, and no tape or glue was necessary.

With the lights turned down a little bit, the Headless Horseman is ready to ride. See some of his comrades in the collection of Lego Abominations.

You can find more Halloween decor projects in our Halloween Project Archive.