Introduction: Jar Light

About: I've always liked pulling things apart - it's the putting back together again that I have some issues with!

I came across some really interesting LED's recently and have been using them in a few builds. They are called filament bulbs and are the same ones you sometimes see in light bulbs. The great thing about them is they only need 3 volts to work and are super bright and diffuse light really well.

This makes them perfect in a build such as this. I also used a coloured jar which helped even more to diffuse the light and give it a warm soft feel. You can use any old jar for this build and get a great result.

The build itself is relatively simple and only needs some basic soldering skills and minimal parts.

So without further ado - let's get making

Step 1: Parts & Tools


1. 2 x aaa Battery Holder – eBay

2. SPDT toggle switch – eBay

3. 1mm ID copper tube – eBay

4. LED Filament – eBay

5. Nice old Jar – I used an amber jar which you can find on eBay or just search around in your grandpa’s garage

6. DC motor – eBay or just pull one out of something. You need the thin copper wire from inside the motor. You could also probably just buy a reel from eBay


1. Soldering Iron

2. Drill

3. Pliers

4. Dremel (not really necessary but they always come in handy)

5. Hot Glue (or good double sided tape)

6. Superglue

7. Small files

Step 2: Getting Copper Wire From a Motor

As you need to thread wire through the 1mm ID copper tube, you’re going to need some very thin wire. The easiest place to get some s from a DC motor. I have a bunch that I have collected so I used one of these. If you don’t have any lying around you can always buy a spool of thin copper wire.


1. First, you need to take the cowling off the motor. This is usually just held into place with a few tabs. Use a pair or pliers or small screwdriver to lift these up and remove the cowling.

2. Inside you will find 3 lots of wound copper wire. Find the end on one of them and carefully cut it away from the motor.

3. Un-wind about 300 to 400mm length.

Step 3:

Step 4: Adding the Copper Tube to the Battery Holder

To be able to have the LED filament in the middle of the jar, I decided to use some copper tubing. The ID is 1mm so the tube itself is very small. I wanted it to be almost invisible inside the jar. I could have just used the copper wire from the motor but the LED would have moved about a lot inside the jar and I didn’t want this.


1. Drill a hole into the middle of the battery holder. It should be the same size as the tube

2. Push the tube into the hole in the battery holder. You want this to be a tight fight.

3. Next, you need to twist the copper wire from the motor. I used a small jig and a drill to do this

a. Bend the wire in half

b. Drill a hole through the middle of a small piece of dowel

c. Push the wire through the hole and tape down with some masking tape

d. Place the dowel into a drill and secure the drill in a vice

e. Hold the end of the wire and slowly start the drill.

f. Once the wire is twisted enough, remove it from the dowel

4. Push the wire through the tube. You will later add a drop of superglue to the base of the tube and wire to hole it into place – not yet though.

Step 5: Soldering the LED to the Wire & Connecting the Battery Holder

Now comes the fiddly part. You need to solder both ends of the wire to the LED filament. The LED filament itself is quite fragile so you need to be careful not to bend it or it will not work.


1. First, you need to remove the enamel covering the copper wire. Grab a file and run it across each end a few times

2. Tin the ends of the copper wire with solder

3. Solder one end of the LED to one of the wires

4. Solder the other wire to the LED

5. Pull the wire through the tube and place the LED so it is vertical to the tube

6. Add a little superglue top the LED and tube to keep it in place

7. Lastly, add a little superglue as well to the wires coming out of the bottom of the battery holder

Step 6: Connecting the Switch to the Lid

The lid that I used wasn’t the original one but it screwed on ok so I went with it.


1. Drill a hole into the lid big enough for the switch to go through. You will be sticking the battery holder to the inside of the lid later on so make sure you leave room for it.

2. Attach the switch to the top of the lid.

3. I also added a O ring and washer to the bottom of the switch to make it waterproof

Step 7: Putting Everything Together

Now it’s time to connect everything up.


1. I had an old battery holder laying around so used this. A new one with have a black and red wires. You will need to remove these by either cutting or de-soldering.

2. Add a little hot glue (or double sided tape) to the bottom of the battery holder and glue it to the bottom of the jar lid.

3. You should also scratch-up the area’s you are going to glue together so the glue has something to stick to.

4. You now have to connect the copper wires from the bottom of the battery holder. If you haven’t already, trim and remove the enamel on each end with a file.

5. Test to make sure you know which is the positive and which is ground by adding 3V to the wires. Once you know, solder the positive wire to one of the solder points on the switch and solder the ground to the ground on the battery terminal

6. Solder another wires (this can be just a normal one) to positive on the battery terminal and then to the middle solder point on the switch

7. Test to make sure the LED turns on

Place the lid onto the jar and admire your handywork

Make it Glow Contest

Participated in the
Make it Glow Contest