Introduction: Working 1-Watt 50mm LED
Hello fellow makers,
Have you ever worked with a 5MM LED and wished it had just a little more light output?
Introducing the 50MM LED!
10 times BIGGER...
10 times MORE OUTPUT...
And they said bigger isn't always better!
Let's start making your own...
Step 1: What You Will Need:
To make this project you will need the following:
- 2 part deep casting epoxy resin
- Access to a 3D printer for the mold
You can also make the mold by hand if you don't have access to a 3D printer eg. Carving it out of polystyrene.
- 1W White LED
- 4mm Brass/bronze rods
- 1mm Brass/bronze plate
- Solder
- 4mm Wire
For the finished LED leads
- ~6mm Heat shrink
- Sanding paper
- Butane torch
-2 Part fast cure epoxy glue
Optional:
- Release agent
I used PVA release agent but this can be whatever is recommended by the epoxy manufacturer or even wax.
- Plating solution
- Power supply
- USB male connector
- Resistor
*As an Amazon Associate I receive a small percentage from sales made through provided links at no cost to you, this helps fund future projects.
Step 2: Updates:
A big shout out to robertslassiterfor showing me these DIY water globes that look pretty dang close to a 5mm LED, you could replace the entire resin lens with this or use them instead of the 3d printed mold and fill these up with resin to skip all the prep work, sanding and spraying.
Get these over at > Amazon - DIY Water globe kit 4pcs
Step 3: Design the Mold:
First we will need to design the mold that will be used to cast the lens of the LED.
I used Fusion 360 for this, the design is really simple and consists only of two circles that I extruded and then finished with a 25mm fillet.
Next I created a shell around the design to form our mold.
I later design a peg type holder that keeps the leads of the LED together whilst assembling.
Step 4: Print the Mold:
After exporting the files to stl's I printed both parts in PLA.
If you can I would recommend rather printing the mold in either PETG or ABS filament as the heat generated by some resin when curing might cause the PLA to deform.
My print settings used were:
Material: Sunlu Grey standard PLA
Speed: 60mm/s
Layer height: 0.2mm
Temp: 230 deg C
Cooling: 100%
Nozzle: 0.6mm
No supports needed
Step 5: Make the LED Components: the Reflector Cup
I had a couple of goes at making the reflector cup and this is the method that turned out the best.
I started with a 15mm brass pipe (but copper pipe would work the same and is easier to get hold of) cut to about 10mm in length.
Grab the pipe with some pliers and heat it up with a butane torch until it is glowing red then quench it in water, this will anneal it making it easier to shape.
Next I placed it onto the head of a ball point hammer and started shaping it around the ball point using another small hammer.
I repeated the annealing process when the metal got harder to shape, this also prevents it from cracking.
I continued until I had a cup that was nice and smooth.
Step 6: Make the LED Components: the Posts
Now for the posts.
I started by cutting a 450mm 4mm brass rod in half for the two legs of the LED.
Next we need the anode and cathode plates that will be cast inside of the lens.
I also cut a small round piece out of the plate to create a bottom for the reflector cup.
For this I used a piece of 1mm thick brass plate that I cut a 30mm by 15mm rectangle from using a diamond Dremel cutting blade.
Then cut the rectangle in half diagonally about 2/3rd of the way as pictured.
Step 7: Soldering:
Now with everything cut out we can start assembling the leads.
I first took some wet 220 grit sandpaper and just refined all of the edges and sanded away any obvious imperfections in the metal.
Next I started by soldering the bottom of the cup into place and sanding it flush, then solder the rest of the pieces together like in the picture.
Note that because it is such a large piece of metal you will need to keep the soldering iron on the piece quite a while until it absorbed enough heat for the solder to start flowing.
Step 8: Optional: Plating
This is optional but does make it look like the real thing.
I plated mine using an old long out of production tin plating kit and had no luck in finding a similar kit on Amazon but they do stock the nickel plating solution that works just as well or you could even have a go at creating your own nickel plating solution.
Before plating I sanded both pieces and went over it with a rubber polishing bit just to get a smooth finish.
Make sure that the pieces are free from any oil residue before trying to plate them.
Step 9: The Light Source:
Now for the most important part... The light!
I'm using a 1 watt cool white LED for mine.
I start by placing a small blob of solder on the inside of the reflector cup near the positive terminal, next making sure of the polarity of my LED chip I placed a drop of CA glue onto the underside of the LED and soldered it to the inside of the cup(the body of the cup is the positive connection).
Now for the negative connection I took a piece of nickel plated copper wire (but you could also use a single strand of wire from a stripped cable) soldered it to the LED's negative leg and then to the negative lead of our 50mm led.
To simulate the phosphor layer that is present in a white LED I used some clear fast set 2 part epoxy mixed with a drop of lime yellow paint and filled the cup with it.
Step 10: Prepping the Mold:
To get a better end result I decided to smooth out the mold a little.
Start with a coarse 220 grit sandpaper and smooth out the inside of the mold then move to a 400 grit and get rid of the scratches left by the 220 grit.
Next I aligned the two parts of the mold and stuck them together with some painters tape.
I used play-doh to fill in the seam in-between the two halves to prevent the epoxy resin from leaking out.
Now we need to give our mold a good coat of release agent and leave it to dry.
Step 11: Casting the Lens:
It's time to cast the lens!
With the lead holder attached position the cup in the centre of the mold, I used a drop of glue on the holder to prevent the leads from moving.
Now mix up approximately 150 grams of resin according to the manufacturers instructions and let it stand to let the air bubbles introduced into the mixture while mixing rise to the top.
When your resin is clear slowly start pouring it into the mold until it is full, I tilted my mold slightly so that trapped air in the cup could escape.
You can pop any air bubbles on the surface using a butane torch.
Set aside to cure completely.
Step 12: Sand and Paint:
After 24 hours curing it's time to pop it out of the mold.
Unfortunately mine had a bubble on the top of the lens due to a small leak, luckily this was an easy fix with some quick set epoxy.
Time to grab some 220 grit sandpaper and soapy water and sand away those pesky layer lines, after the 220 we can move to 400 grit to smooth it out and get rid of any scratches.
Next we need to apply a layer of clear lacquer, this will give you a crystal clear lens and protect the resin from UV rays that will eventually turn it yellow.
I mixed up a small amount of clear coat in my airbrush but a can will work just as well.
Spray a few layers until you have a nice even layer over the lens.
Leave to dry completely.
Step 13: Adding the Finishing Touches:
I wanted to use my LED as a lamp so to finish it off I bent the legs to form a stand.
Next I soldered some 4mm red and black wires to the legs and covered the joint with heat shrink.
To the ends of the wire I connected a male USB connector and current limiting resistor so that I have can just plug my new lil' LED lamp in anywhere.
Step 14: Enjoy!
I hope you guys enjoyed this Instructable, if you have any questions please feel free to leave me a message or comment bellow.
Please share your own creations with us by clicking the "I Made It" button below.
Happy making!
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First Prize in the
Go Big Challenge
46 Comments
1 year ago
Build this giant 555 timer to flash it:
https://www.instructables.com/Giga-Max-555-the-Giant-555-Timer/
(You will need to add circuitry to increase the 555 output current!)
Reply 7 months ago
If yer gonna make a super-sized 555, ya need to use super-sized internal parts (super-sized compared to what's inside a "real" 555, that is) and not just a box around a "real" 555.
Working "MEGA 555" : 32 Steps (with Pictures) - Instructables
9 months ago
Very nice project! Congrats! Paulo, Brazil
Tip 1 year ago
Bravo , Its a new idea .
1 year ago
Really nice idea. I had never thought of doing this. the only modification I made was to polish the inside of the reflector. It really made a difference.
1 year ago
Three comments for a very impressive project:
Need to add a “flat” to the perimeter of the skirt.
Could use square “wire” for even more realism.
Heating and quenching doesn’t anneal/soften metal, it hardens it. Slow cooling softens.
Reply 1 year ago
Thank you :)
It's not clear in the photos but there is a flat spot in the brim on the positive side.
You are 100% correct with the square wire, unfortunately the only ones I could find online is square machining stock and it's a lot more expensive and not available to me.
Non-ferrous metals soften by heating and quenching or you could just work it hot but it's much more dangerous.
Reply 1 year ago
"Heating and quenching doesn’t anneal/soften metal"
As the author says, it does with copper etc. I know heating and quenching hardens steel and probably other ferrous metals.
Reply 1 year ago
I learn so much from Instructables!
Reply 1 year ago
Me too!
I find it's also a nice community, where people look to help each other, rather than looking to put others down, a nice but rare thing on the www!
Tip 1 year ago
Amazing attention to details! I love the tiny "bonding wire". But...
It is quite unusual for 5 mm LEDs to have the anode attached to the cup. Was it because the heat pad of the actual LED was connected to the anode and you wanted to avoid short-circuit?
The big violation though is that the flat side of the LED is also facing the anode. This is almost unforgivable, since it is the only feature that by definition tells the polarity of an LED after the wires are trimmed.
Reply 1 year ago
The size of the electrode, interior to its casing, is an indicator of polarity, also. A colleague once mentioned his memory helper was, "The gitter is bigger than the shitter." This phrase momentarily seemed to be backwards to me until I realized that he was speaking in terms of conventional current flow, and I was thinking in terms of electron flow. After that realization, the world once more made sense.
1 year ago
Hahaha... very nice cool idea. when I saw the title I did not comprehend what I was reading.
You made the inside look just like the construction of the manufactured LED. Very nice. Thanks for sharing.
1 year ago
Very cool project. Well done.. But I have noticed that you said that the leg with the cup is the positive? Well I think it is the negative or Cathode. The Anode, or positive should be the leg with the whisker (wire). :)
https://en.wikipedia.org/wiki/Light-emitting_diode
But as this is not a real LED, who cares as long as you know where to connect the positive and negative :) As I said, very nice project, thanks for sharing..
1 year ago
1 year ago
This is awesome!
It's so big, one could make a really cool scaled up beginner-level project LED floor lamp with a giant 9V battery with connector, soldered to a giant switch, with a giant resistor....that would be awesome!
1 year ago
Anyone know if you could dye the epoxy for colored LED?
Reply 1 year ago
You could just use a colored LED.
Reply 1 year ago
You definitely can, I first wanted to make it opaque so that it diffuses the light when using it as a lamp but wanted to clearly show the internals for this Instructable.
1 year ago
Wow! That is very cool project! Thinking of making one for a giant torchlight :-D