Hot Glue LED Diffusion




About: depotdevoid is short for The Depot Devoid of Thought, the place where you go when you lo...

What would I do without LEDs and hot glue? They are integral components to nine tenths of my projects. Well, while I was working on my first instructable I noticed that the LEDs I'd hot glued onto the wires kind of made the translucent glue glow a bit. I thought to myself, "What would happen if I put the glue on the focus end?" And so, this instructable was born.

Usually when I'm diffusing a "Water Clear" LED I grab the sandpaper and go to town, but this works just as well if size isn't a problem, and looks better in the end.

***UPDATE 5/3/10:  Hey, if you make your own Hot Glue diffused LED project and post some pictures in the comments section, I'll give you a patch!***

Step 1: Gather Materials

Okay, this is the hard part! You'll need:

1. LEDs
2. Hot glue sticks (low temp or multi-temp)
3. Hot glue gun

Man, that was hard. I got tired just writing that exhaustive list. You may also want some sort of breadboard, some resistors, maybe a thumbtack and a couple of toothpicks. If you're reading this, you probably already have all of those things.

Step 2: Glue!

Alright, now decide if you want to go with low temp or high temp mode. High temp means you have more time to shape the glue, low temp means it doesn't take as log to dry. Get ready for some hot glue-on-LED action!

Okay, I lied about the last step, it really wasn't that hard. THIS is the hard part.

1. Hold the glue gun in your right hand, or left hand if you're a lefty (or your left hand if you're a rebel! Or your right hand if you're a Leftist Rebel, you Commie!)

2. Hold the LED in your other hand by the leads

3. Now, VERY CAREFULLY put some GLUE on the LED. Be VERY, VERY CAREFUL!!! This is just like when the ghostbusters crossed their proton streams, and you might just cause a rip in the space-time continuum!

4. But seriously, at this point you'll have to kind of be careful about where the glue flows. If you watch where it's going and keep the LED in motion for a while, you'll be able to get it into a pretty regular shape.

5. After about a minute or so (depending on temperature and how much glue you used) the glue will stop flowing, but it will still be somewhat tacky for a few minutes, so if you've got a spare alligator clip, you might want to clip the LED somewhere it won't touch anything. You probably don't want fingerprints or other gunk in the glue.

Step 3: Done?

So there you have it, a nicely diffused LED, without using any sandpaper. I think they're pretty ascetically pleasing this way.

Of course, about five seconds after I'd finished the first one, I realized that if some glue looked good, more glue might look better . . .

Step 4: Sculpt!

So, why not add some more glue? Why shouldn't you add a LOT more glue? The LED doesn't have to have a simple round bulb, why not play around a bit? Grab that toothpick and the thumbtack and use them to sculpt the somewhat tacky, but not fully dried glue.

Here are some shots of the work in progress:

Step 5: Final Thoughts

So, this was a fun way to blow an hour. I made a pile of interestingly shaped LED bulbs, and in fact I had an idea for my next instructable that will follow soon.

I'm really not sure what I'm going to do with these. I've been making sun jars left and right, so I might see what one of them looks like in the jar, without frosting the glass. I'm also thinking I might get a string of LED christmas lights this winter and make individual bulbs for each light.

It might also be fun to make some sort of an injection mold and make interesting shapes for the bulbs that way. I'm not really sure how that would work, especially the part about making sure the glue doesn't stick to the mold. If anyone has any thoughts on the matter, I'd love to hear them.

Please leave a comment, positive or negative, and also please rate this instructable. I'd really like to know what you all think about this instructable, my writing style, the idea itself, etc. It's hard to tell what people think when you have 2800 views and only 8 comments, like on my first instructable. I'd also like to see pictures of any interesting glue sculptured LEDs you make yourselves.

Most importantly, thanks for looking, and I hope you enjoyed it!

Remember, anyone who posts pictures of their own hot glue diffused LED project in the comments gets a DIY patch!

Participated in the
The Instructables Book Contest



    • Stone Concrete and Cement Contest

      Stone Concrete and Cement Contest
    • Growing Beyond Earth Maker Contest

      Growing Beyond Earth Maker Contest
    • DIY Summer Camp Contest

      DIY Summer Camp Contest

    130 Discussions


    3 years ago

    How well do you think the led would refract if say an entire glass coke bottle was filled with hot glue and the LED was at the top?

    Looks like I'm five years late with my comments but glad I found this! Yours is a very cool idea that I'll play with later - what I was looking for was reassurance that gluing fine glitter to LED xmas lights wouldn't cause a meltdown... (I have a string I use on the mantle that has too harsh a bulb, I'm thinking the glitter would subdue the light and leave a ...more sedate? subtle? ...sparkle. Any thoughts? (Elsewhere on the web i read that gluing glitter to a bulb was asking for disaster -- too stupid to contemplate (well that's me) --but LEDs are cool, right?)

    1 reply

    I'm no expert, but as long as they're LED bulbs, you should be fine! You're right, they're cool so there shouldn't be a problem.


    5 years ago on Introduction

    cool I like I. I didn't really get the point but once I saw that you were interestly shaping the led to looke amazing I started to dig it.

    1 reply

    5 years ago on Introduction

    I am experimenting with collage/decoupage glue to see what will happen. I had to order some LEDs for throwies, but they didn't have the warm white diffused, so I tried your method, which works really great, and since mine are just going into paper lanterns, I poured some modpodge in a cup and dipped the bulb to see if that works. I love all your fancy shapes! I just needed to diffuse mine is all.

    1 reply

    8 years ago on Step 5

    what about using resin molds with clear silicone rather than hot glue? i've made quite a few molds for use in my soap making. normally you'd make a resin mold then use that to make a silicone one, so it would be like making silicone molds over and over, each with an led in it. the silicone is going to be sturdier than the hot glue, too. hot glue tends to get brittle over time, and has a tendency to break bond with non porous surfaces when handled much. but, that can be used to your advantage, you can use a nonstick surface to help manipulate the hot glue into the shape you want, rather like when you're working with molten glass. you could also use other techniques used in glass (lampwork) bead making, like making your base shape and using another color of glue, or glue with glitter in it to add patterns of spirals or dots, etc. i'd think you can take loose glitter and sprinkle it on before the glue dries....and there are a lot of different kinds of glitter, from super fine to translucent to shapes. you could do some really fun things using large LEDs and lots of glue...make flame or flower shapes, etc. could be really fun!

    2 replies

    What I did once was buy some of those silicone baking trays, and just pour resin straight into those. You can get some interesting shapes and come out with an easy-to-remove resin LED mold.


    Reply 8 years ago on Step 5

    Hmmm, I hadn't thought about this instructable in a while . . . thanks smiddenkidden, I think I may just have to revisit the idea of making molds!


    7 years ago on Step 5

    I've been trying to think about how to add the finishing touches to a project for my daughter. I googled leds and hot glue and this came up. It is perfect for what I was thinking. Makes my idea so much better now that I've seen it. Thanks for taking the time to write this up!

    1 reply

    Reply 7 years ago on Step 5

    Fantastic, I'm happy to hear I helped out! Please post some pictures of your project, I'd love to see what you did with it!


    9 years ago on Introduction

    this may have been answered already but i saw some one was trying to come up with how to mold it in the 3rd par of this link its talking about using ceramic tiles with clear embossing ink on it to work with the glue and remove it easy im sure a mold could be made this same way.


    9 years ago on Step 5

    thanks heaps this helped alot =) im making the glowing cube instructable and didnt want to fill it with hot glue

    3 replies

    Reply 9 years ago on Step 5

    Glad I could help magiccowy!  Which instructable are you doing?


    9 years ago on Step 5

    This is a great Instructable
    Have you tried a RGB or multiple LEDs clustered into a BIG bulb?