Last month I was inspired by a Tweet by Erin Riley that ran across. She had an excellent inexpensive & very easy electronics / hot glue gun project.
glue gun + silicone mold + LED = gummy bear lights! pic.twitter.com/wSlBkufYXv
— Erin Riley (@eeriley99) February 15, 2017
This gave me some great ideas for a future Cub Scout meeting for my son or an upcoming birthday party for my daughter or just a cool not so run of the mill rainy day project… but why not an over the top bling for the Cub Scout Pine Wood Derby.
First the materials… I bought everything off Amazon except for the batteries and the hot glue gun… but I’m sure you can get those there too. Here I’ve linked right to the exact items I bought.
- 2 Pack (136 Bears) Gummy Bear Candy Mold – 68 Cavities – Bonus Dropper & Recipe Card – Food Grade, 100% BPA Free & FDA Approved Silicone – Perfect For Chocolate, Jelly, Ice Cubes Too Note that the one I was sent was blue but the color doesn’t make a difference. I also have no use (yet) for the dropper. Also once you’ve used the molds with the glue I wouldn’t advise using them for candy.
- Chanzon 100pcs (10 colors x 10pcs) 3mm Light Emitting Diode LED Lamp Assorted Kit Warm White Red Yellow Green Blue Orange UV Pink These come in 10 different colors… but I’m hard pressed to tell the purple from pink.. meh.. they work. The green is EXPLOSIVE green and my personal fav.
- uxcell 3Pcs CR2032 CR2035 Coin Button Cell Battery Holder on/off Switch Here’s the “kick it up a notch” item. Tad more expensive at $3 each but adds the wow factor. These holders take 2 CR2032 coin batteries and have a switch on the side that does not only on/off but BLINK! BONUS!!!
Making the LED Gummies
To assembly the LED gummies… fill one mold about 1/2 way with hot glue making sure to get into the nooks & crannies that make up the bears face & arms. Then place and LED into the middle of the mold. Cover up the LED with more hot glue.
At this point a quick tip on how to place the LED… On an LED one of the leads is longer than the other. This is the positive lead. The first batch of LED gummies my daughter and I made had the leads mixed… meaning some times the positive would be on the right some times on the left. Once these cool and you start bending them a bit it’s tough to figure out which is which. So decide on which side to put the positive lead and stick with it. This helps immensely when and if you’re going to be wiring up your LED gummy bears to something else. Why? Well as my daughter and I learned from SparkFun.com an LED is a diode and a diode only allows electricity to flow in one direction. This means if you try to put the positive (longer) lead to the negative side of the battery NOTHING WILL HAPPEN. This made us think that we had about a 50% failure rate on on bears… and lead me to do some quick googling.. (Yeah… I know… didn’t even dawn on us to turn the battery around! DUH).
So once you’ve covered the LED with hot glue let the glue cool down in the mold before taking it out.
Attaching to Pine Wood Derby Car
Our next step was to attach the uxcell battery holder/switch to the LED leads on the gummy bear. The uxcell holders come with about a foot of wire so unless you have a project which needs this much wire, you’ll have to cut down the wire and strip it closer to the hub. To mount it to the pine wood derby car we used a few dots of hot glue and set the holder into it with the wires facing forward (to where our LED gummy bear will be) and held it there for a few moments until it set.
Next set the gummy bear into position. With another drop of glue position the LED gummy where you want it to go… making sure that it’s within range of the wires coming from the battery holder. Connect the gummy bear to the leads coming from the holder making sure that your wires aren’t touching and thus causing a short. At this point, if you’re a real pro, you could solder the wires together… or if you’re like me and my six year old daughter and don’t have a properly vented area in which to solder things together… or just don’t have a soldering kit… get the glue gun and drop a nice big blob of glue over the wires. Again making sure that the two connected wires aren’t cross touching one another.
Ready for the Race Track
Here’s the final product. We might not win any awards, especially with a bum wheel that we “accidentally” hot glued to the side of the car, but we’ll sure be in the running for the most decorated car.
Realized that it’s hard to see the blinking LED gummy bear without a video so here it is in action.