Introduction: Hot Glue LED Diffusion

Picture of Hot Glue LED Diffusion

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

Picture of 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!

Picture of 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?

Picture of 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!

Picture of 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

Picture of 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!


tinkerman92 (author)2015-09-28

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?

stephanie.cavanaugh.5 (author)2014-12-05

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?)

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.

ToggleSwitch (author)2014-05-27

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.

depotdevoid (author)ToggleSwitch2014-05-27

Thanks! It's pretty fun to play around with the shapes you can make.

Happymoose (author)2013-10-18

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.

depotdevoid (author)Happymoose2013-10-18

Thanks, I'd love to see how yours turn out!

smiddenkidden (author)2010-08-27

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!

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.

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!

aspittal (author)2011-08-23

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!

depotdevoid (author)aspittal2011-08-24

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!

techturtle2 (author)2010-07-19

My hot glue diffusion

depotdevoid (author)techturtle22010-07-20

Nice, thanks for sharing! Your patch is on the way!

chy (author)2010-03-08

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.

Doddity (author)2009-12-02

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

depotdevoid (author)Doddity2009-12-02

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

Doddity (author)depotdevoid2009-12-20

alexanders led cube

depotdevoid (author)Doddity2009-12-20

Sweet, I'd like to see pictures when you're done.

nein166 (author)2009-11-22

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

depotdevoid (author)nein1662009-11-22

Oh, I absolutely have!  Unfortunately, I accidentally burned out one of the LEDs in my BIG RGB bulb (it was about 1 1/2" across) before I took any pictures.  You can see a smaller version at this instructable that I did a while back.

Vspec (author)2009-09-27

Nice instructable, i just used this method of diffusion on a usb powered keyboard light i made.`

depotdevoid (author)Vspec2009-09-27

Thanks Vspec, it's always gratifying to hear that someone has made use of your instructable. Do you have any pictures?

Tommyhzy (author)2009-03-19

A faster way to do this with multiple LEDs is to set up kind of like a factory - Heat up a bowl of about 20 glue sticks in a small cup Dip the LEDs in the heated glue Use alligator clips to hold the LEDs Dip more LEDs while the first batch is cooling While the second batch is cooling, shape the first batch While the first batch is finishing off cooling and hardening into a final shape, shape the 2nd batch that is somewhat tacky Wait for about 2 minutes or place in freezer for 30 seconds You're done 2 batches of LEDs!

depotdevoid (author)Tommyhzy2009-08-12

Hey, I missed your comment until just now, I think that's a great idea, have you tried it?

Tommyhzy (author)depotdevoid2009-08-12

Of course! Back in March, of course... (:

tensiga (author)2009-07-07

about the glue not sticking to the mold after months of playing with hot glue i found out it comes of whatever u stick it on pretty easily if u pour some water on it

depotdevoid (author)tensiga2009-07-08

Good to know. I've never gotten around to trying molds myself. Do you have any pictures of your work?

nert (author)2008-09-11

"especially the part about making sure the glue doesn't stick to the mold" I was thinking PVA, but the warm temp mike make ituseless. How about a teflon spray like Elmers 'Dry Slide'

a.cowen (author)nert2009-06-11

You could use something like vaseline to coat the outside of the mould. Or if it does stick use a hot knife to cut it out, as the glue will melt again? Perhaps.

websurfer1232 (author)2009-06-06

I found this.
Fired up the glue gun.
Made this.

Nice pic, that really looks like fire!

stonechild (author)2009-06-01

I was looking for a way to encase LEDs with a glue gun. I want to build an 8 x 8 LED cube. One that I saw had the LEDs encapsulaled with glue and it looked pretty good. Now I know how to do it. Now to look to see if you've reported on molding the glue which I'd like to do. Thanks for a perfect instrcuctable.

depotdevoid (author)stonechild2009-06-02

Thanks for the comment stonechild, I'm always happy to hear my instructables have been helpful. Unfortunately, I never got around to actually using molds with the glue, but if YOU do, please put it in an instructable! I'd like to see what your cube looks like when it's done, too.

Kaze (author)2009-02-17

This is my favorite new instructable! Having the various finished photos at the end is perfect and really shows how cool of an idea this really is. Great length, easy to follow, nice photographs. Keep the guides coming!

depotdevoid (author)Kaze2009-02-17

Thanks for the feedback Kaze, I hope you get some good use out of this instructable!

Zippy_Pyromaniac (author)2009-01-21

Ima make a color changing glowing thing!! Ill post back with images soon

Sweet, I can't wait to see it!

camperken (author)2008-12-14

I had another thought for you. I industrial molds they use a spray called mold release. Don't remember the brand but when parts start to stick they spray the molds before the plastic is injected. Molds by the way have pins built in that push the parts out. Rubber molds I've seen the parts were just carefully pulled out but this was low volume

camperken (author)2008-12-14

I thought this was great. I'm daydreaming now about what sorts of LED lights to make. I once made a mold out of aluminum and using peanut oil to heat delrin (a plastic)) and it also lubed the mold. Maybe molding acrilic plastic. I did that once to make a new tail light for an old VW van. What about several LEDs, different colors, which would connect to different parts of some glue world. Light would flow I'd think. Have a way to vary each LEDs intensity or on-off. BUt yours is great as is

daniel! (author)2008-12-13

pretty lights cool, great idea

J W Hendry (author)2008-09-17

bright eyes

codongolev (author)J W Hendry2008-12-04

I would ask why.... but you can't explain awesome.

andrew13 (author)J W Hendry2008-11-12

tht........ is frickin awesome.

depotdevoid (author)J W Hendry2008-09-18

Nice! Thanks for sharing, and for the advice!

j0nip (author)2008-11-28

brilliant. I am going to make a glowy fire type thing using this. thank you.

depotdevoid (author)j0nip2008-11-28

Great, I'm glad you liked it! Post a picture when you're done!

robotmastern (author)2008-10-31

you could try exparamenting with lost wax casting ( im not shure of the melting points of glue vs. wax but aslong as wax is less it will work) this procces is not reproducable however it can make more elaborate designs

Maxence (author)2008-10-29

Nice project, I love it. Just a question: I don't have a hot glue gun, so, would it work with wax? I used to drop melted wax in a glass of water when I was younger, and it made pretty cool shapes, so, that reminded me of this when I saw the project and made me wonder if this would do it too.

depotdevoid (author)Maxence2008-10-29

I suspect wax would work, but it's a lot less translucent than hot glue so you might have a problem there. Hot glue guns are actually really cheap, you can buy them from craft stores for around 8-15 dollars. In fact, I saw one at my local goodwill the other day for 2 bucks, so you might check that sort of place. If you do end up doing some of these, post a picture! I'd love to see the results!

About This Instructable




Bio: depotdevoid is short for The Depot Devoid of Thought, the place where you go when you lose your train of thought and you're waiting ... More »
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