Introduction: How to Cut a Light Bulb in Half

Picture of How to Cut a Light Bulb in Half

In this Instructable, we'll have a look at one of the ways to cut light bulbs in half.

Once the bulb is cut in half, you can put in a large object and glue the bulb back together.

We will need:

  • Empy/Hollow Bulb
  • Nichrome Wire
  • Copper Foil Adhesive Tape
  • Battery from a drill or alternative power source

If you are Interested in a video version of this Instructable and the embedded video does not appear on your mobile device, here is an alternative link

Step 1: Put a Nichrome Wire Onto the Bulb

Picture of Put a Nichrome Wire Onto the Bulb

Take a piece of nichrome wire, twist it to make a loop.

Slide it onto the bulb.

It should fit tightly.

Step 2: Secure the Wire With a Copper Tape

Picture of Secure the Wire With a Copper Tape

Secure the wire to the bulb with a copper tape.

Put 2 pieces of tape on each side of the wire twist.

Step 3: Separate the Wire Twist

Picture of Separate the Wire Twist

Cut off the twist and separate the wire.

Step 4: Prepare Your Power Source

Picture of Prepare Your Power Source

Prepare your power source.

I used a battery from a drill.

It's a 24v battery, but lower voltage batteries should also work.

As long as the battery has lots of amps, it should work.

Most of the power tool batteries will be powerful enough.

The power source will also depend on the nichrome wire you use.

Thinner the wire, less powerful battery you will need.

Step 5: Cut the Bulb

Picture of Cut the Bulb

Put the positive cable to one end of the wire and the negative cable to another end of the wire.

The wire will start to glow.

Be careful as it will become extremely hot

If the wire does not light up in 2-3 seconds, your battery might not be powerful enough.

If the wire burns out, that means you have too much power.

After a few second of heat, the bulb will split in half.

Don't worry if there is a piece of glass that is uncut (the part where the wire did not touch).

It will break once you try to separate the glass.

Step 6: What's Next?

Picture of What's Next?

With a bulb cut in half, you can make something cool.

I put a large pad-lock in the bulb and glued the bulb back together.

If you look closer, the line is visible, but it still looks impressive.

If you want to hide the cutting line, you can try to use a window color to draw something on top.


sveedio (author)2016-10-25

Just curious, could you cut thicker glass with it

Dawsie (author)2016-09-08

that's so cool :-) as for glue there is a glue that you can get for fixing wine glass and that sort of thing I used years ago to fix a set of wine glasses and you could not tell where I had fixed them :-) you can get the glue from a good hardware store in the section the gave for all their glues :-) that's where I bought mine years ago :-)

Will gave to buy some of those bulbs to try the trick :-) love it and if I make a special stand for it to sit in I could hide the glued line behind the stands ring for holding the bulb :-)

Thanks for a great idea :-)

xenobiologista (author)2015-09-01

Where can you buy or easily scavenge nichrome wire from?

Laral (author)xenobiologista2016-09-06

I was wondering the same thing. eBay has it at good prices - nichrome wire | eBay. If you're willing to wait, this guy - Nichrome Wire 32 Gauge 0 2mm KANTHALA1 Cantal 100 ft Resistance Resistor AWG | eBay - is selling 100ft of 32GA for $1.96 from China.

Peterd92 (author)xenobiologista2016-09-04

I found it on

Angelbane (author)xenobiologista2016-09-04

You can buy it from vape stores as they use it in the homemade vaping equipment.

Think you can try guitar cord as well but try a thin gauge cord to start off with. Used this in a foam cutter they heat up nice.

OK thanks for the info both of you.


Nokota (author)2016-08-23

Seriously, what kind of glue did you use? The line is barely visible and the whole thing looks better without the glass paint, personally, I think. This whole instructable is useless if you don't tell us what kind of glue you used to make such a seamless and strong bond when putting the glass back together. Several people have already asked.

fauxgal (author)Nokota2016-09-04

Use can E6000. But apply it with a toothpick point. You have to be very careful to pick up only a tiny bit on the point each time you grab glue

Laral (author)fauxgal2016-09-06

I use E6000 and it is great, but it is way too viscous for this purpose. Regular viscosity cyanoacrylate glue (Superglue) would be best. It flows really well. You could apply it with a pin or toothpick.

Calcfan (author)2016-09-05

The bulb could also be cut diagonally to be slightly less obvious. Calcfan.

Peterd92 (author)2016-09-04

This looks way cool and i want to try it. What gauge is the nichrome wire? I see it comes in a variety of gauges (20g, 24g, 26, 36g, and probably others).

Other than that question, this was an excellent video!

arekaybee (author)2016-02-17

Would this process work to make a hole in the bulb?

EmillyBint (author)2015-08-27

Nice idea. I also love these two ideas. Do you have an idea how to cut the metal part?

JayLundgren (author)EmillyBint2015-10-31

Emilly, you can cut the metal part with a Dremel tool and a cutting disc.

This is a really nice idea!

JoyM10 (author)EmillyBint2015-09-13

Emily, you should do an instructible segment on this idea.

JoeGlancy (author)EmillyBint2015-09-01

You can remove the metal part, it was on another features Instructable and I simply cannot remember which, but it is possible. It might also be nice to, if possible, use the same wire to make small holes for air ventilation if you're going for the plantpot idea, which has caught my interest too

xenobiologista (author)JoeGlancy2015-09-01

I think this is the one

grayseep189 (author)EmillyBint2015-09-01

They also make special jars that look like light bulbs with a screw on/off top .


bungee- (author)EmillyBint2015-09-01

The metal part can be de-soldered from bulb and then cutting crafting can be done with tools of your choice.

Raitis (author)EmillyBint2015-08-27

I'd suggest some rotary cutter (Dremel). Cutting with knife/scissors is possible since it's soft, but if the part next to the bulb deforms, the thin glass of the bulb might shatter and that's never good while holding it in hand. Thick gloves are a must while working with them anyway, the shards are nasty. (:

EmillyBint (author)Raitis2015-08-28

Wow, looks like I'll have to delegate the project to my brother :D I had a bad experience with a bulb exploding over my head when I was in school and I still can't change bulbs when I need to, lol.

You might be able to cut the metal with large scissors (when it's removed from the bulb).

Usually the metal is soft-ish

Then there is a dremel tool.

You can definitely cut it with that.

I can't say from the experience as I have not done it.

That's what I would try out.

If you try it out, please let us know.

wragy (author)2015-09-26

you can get nichrome wire, (a lot of it) from an old broken toaster or your wifes brand new one. lol made it! (author)2015-09-21

Almost nailed it!!! I´ll keep trying.... Lol!

TanmoyB1 (author)2015-09-09

very good,,,,,

dragonrising (author)2015-09-08

This looks awesome! Will try!

ajarb (author)2015-09-07

Would this work with old radio valves?

LaserDave (author)2015-09-04

Terrific ideas for lightbulbs, both here and your other 'ibles.

I've done exactly this many times for various projects, and I found that the gap for the connections to be a pain. Most times the gap will follow the rest of the crack, but sometimes it doesn't. I came up with a better solution that works 100% every time.

All you do is make your loop in the way shown in the video, but don't cut the wire for the loop. Simply select two locations along the wire that are opposite each other, and touch those points with the two wires from your low-voltage (such as 12v 1A) power supply. Of course you could also secure those wires onto the nichrome with the same copper-foil strips.

Another tweak that I've found helpful, is to put the bulb in the freezer for 30-minutes just before heating the wire. The extra coldness of the glass makes the process faster and more certain to work on the first try.

Lastly, there are products being sold in automotive departments for the purpose of repairing (or at least "appear to be" repaired) chips and cracks for windshields, that may be used for hiding the line from the break. I have used various clear epoxies, thick super-glue, silicones, and another type of silicone described as "flowable" with fairly good results for hiding the crack. But in all cases, the line will be less obvious but don't expect the miracle of getting the break line to be perfectly invisible.

GrfxGawd (author)2015-09-03

Recently a bunch of UV cure epoxy and resin have hit It's mostly sold to those who've crashed their smartphone screen. Some pictures of actual repairs show screens where the fracture is no longer visible. UV cure epoxy and resin has been used for quite some time with plate glass and acrylic to make "seamless" structures. Some thoughts for those curious to try.

Hairyloon (author)2015-09-03

What sort of glue did you stick it back together with?

RohanVermaak (author)2015-09-02


Ro_Usr (author)2015-09-02

I would take one huge bulb split it in half and put a smaller bulb inside it .

mahdi32 (author)2015-09-02

درود بسيار جالب بود. ممنون

Gartholameau (author)2015-09-01

Now this is a nice trick. Well done. I've followed your other ibles and am always impressed with your magic. Maybe I can now get that spaceship model to fit in a light bulb. I might also make Christmas ornaments painted on the inside using the reverse painting method similar to Christmas scenes painted on store windows.

Raitis (author)2015-08-27

Would be great to but something inside and then make it light up as well!

Moose Dr (author)Raitis2015-08-27

Good thought, but not that straightforward. The standard lightbulb has a vacuum inside. It may be possible to replace the original light components with LEDs. That would be fun.

Raitis (author)Moose Dr2015-08-29

It's the question of whether a diode bridge, LED and a few resistors can be cramped into the base of the bulb. That is if you want to screw it in a regular socket.

inb4 someone says it - I know that's not the wisest idea, but should work.

Dedawg57 (author)Raitis2015-09-01

We have

a dollar tree here and they sell plugin nite lights that are led's. With a little work the board could be cut into and jumper wires used to complete the circuit. Then just de-solder the prongs and solder the light base to the board and you have a large led bulb...

shomas (author)Moose Dr2015-09-01

Mineral oil is non conductive, yet will conduct heat better than a partial vacuum or air to the larger surface area of the bulb, the prolong the life of the led. Although, im not sure if / or how much light will cause a breakdown of the oil.

ShakeTheFuture (author)Raitis2015-08-27

I was also thinking the same, but laziness won me over :)

tecton47 (author)2015-09-01

I recently stumbled across this site and it has so much stuff that I want to do! I have to prioritize and make a list of supplies and then get started. After that I'll think of something unique that I can do and post it.

Chain N Sprocket (author)2015-09-01


1-big-dog (author)2015-09-01

nichrome wire, and copper tape are both easily purchased on ebay.

dave.callista (author)2015-09-01

Right, now everybody run right down to your local wallyworld and pick up some nichrome wire and copper tape. So where did you get this stuff?

User1 (author)2015-09-01

Aren't you missing that dumb (but I guess necessary) statement about not being responsible if you cut off your fingers or stab your cat?

It's kinda an American thing.

BTW, I like your project here. It would have been nice to see a close-up of the glued seam.

PaPa Ed (author)2015-09-01

Thanks for stimulating ideas for me. Looks like a great project.

About This Instructable




Bio: Innovative Projects, Diy's, Life Hacks
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