A Polycarbonate and LED Christmas Tree Star

star-cropThis Christmas, it was requested that we get a new tree. I voted for a more unconventional* choice, which was agreed to on the condition that I make a star for the tree. I was happy to do it, and though my memory is a bit hazy, I may have agreed to this task before. Nonetheless, this was the year.

After considering a few ways to make it out of paper, it occurred to me that I could attach two pieces of polycarbonate together, and with the correct holes drilled, I could also embed LED lights, similar to how “throwies” work. After a little design work, and cutting with a CNC router and manual milling machine, I had something that attached nicely to the top of our tree. Check out the video to see the build process:

If you’d like to make your own, the DXF I used can be downloaded here. As shown in the video, there’s a little more to it, since you’ll have to drill and tap the holes appropriately, but that should give you the basic outline.

*The “unconventional” tree was a potted specimen, that I thought would be fun to have and bring indoors for the holiday season. It’s a little smaller that we’d like now, but if I actually water it regularly, it should grow with us. Although I didn’t necessarily expect it to be cheaper in the short-term, it was actually quite a bit cheaper than most cut or fake trees.

I suppose this either makes me smart, a cheapskate, or very environmentally conscious, since it should make less of an environmental impact than the other choices.

A Programmable RGB LED Infinity Mirror

Infinity Mirror with top

I’m incredibly happy with how this photo turned out!

An infinity mirror is a one-way mirror setup where the light inside of these mirrors allows you to see in, while reflecting back and forth, appearing to multiply and stretch to “Infinity”

At some point in the last few years I decided to make one of these setups, but after buying some of the parts, this project just kind of sat there waiting to be made. A few years later, now with access to a router that let me easily put 1/8 inch slots to hold the mirrors in strips of wood, I finally made it. Besides an 1/8 inch bit for my router and the one-way mirrors over a year ago, I don’t think I bout any parts for this contraption.

You’ve likely seen this kind of “infinity mirror” effect at a gym or anywhere where you stand between two mirrors. Or, as I ramblingly put it in my “howto” video below, this kind of thing was also seen in the movie Enter the Dragon. It really is an excellent movie, and though I do appreciate cheesy Kung Fu movies for their comedic value and obvious influence on later video games, such as Mortal Kombat and Tekken, that one really stands out as an entertaining movie comedy value aside.

Infinity Mirror Build Details

As for the build, it stands at 15″ high and 7″ wide. It’s made out of furring strips that I had left over from another project. They are about 2 1/2 inches wide, just big enough for Read more »

Hands On with the KeyChainino


If you play with your keys while waiting on something: bus, subway, fish to bite, etc., the KeyChainino might be a good device to have handy. Creator Alessandro Matera was nice enough to send me one of these devices* to try out.

It’s a pretty neat device, and I really enjoy seeing the default Arkanoid-style game played on a 5×6 LED matrix. If you get tired of that, these LED devices can be programmed using an Arduino. Although it’s not as simple as programming an Arduino directly, the task shouldn’t be too hard to execute (I’ve programmed ATTiny chips before using an Arduino, as seen here).

Pins are provided with the board, so don’t discard them, or things will be slightly harder if you want to change the program around. Several programs, or sketches are available on the Keychainino site, though it would seem the real fun would be in creating or modifying your own programs. Granted, I just received this board and haven’t tried it yet, but that seems like the real fascinating thing about this little project.

Check out the video after the “read more” to see it in action: Read more »