Introduction: Flamethrowing Jack-O'-Lantern

Picture of Flamethrowing Jack-O'-Lantern

A flamethrowing jack-o'-lantern keeps the trick-or-treaters a safe distance from your house and is a fine addition to any anti-Halloween arsenal. At the first sign of any sugar-obsessed imp, simply press the trigger button and wirelessly shoot a one-second burst of flames out of the jack-o'-lantern's mouth. This plume of hellfire will make even the most bold of people think twice about approaching your door. Very few people are willing to risk life and limb for the chance of a tiny box of milk duds.

WARNING!: This pumpkin is extremely dangerous and you definitely should not make one of these. The instructions were posted here are for entertainment purposes only. I do not condone the manufacture or use of flamethrowing jack-o'-lanterns. Seriously, nothing good will come of making one of these. Don't do it.

Step 1: Go Get Stuff

Picture of Go Get Stuff

For carving the jack-o'-lantern, you will need:

- A large pumpkin (mine was probably about 18" in diameter)
- An assortment of cutting knives. Serrated seemed to work the best.
- A marker
- Paper and pencil
- Scissors
- A spoon
- Other scraping implements. I found a chisel worked very well.

For the remote controlled flamethrower:

- Door lock actuator
- SquidBee transmitter and receiver. I had these lying around from a previous project. Any Arduino/Xbee combination should do.
- An extra ATMEGA168 or ATMEGA28 (only if using the Squidbee setup above as the receiver has no chip)
- Small can of WD-40
- 12" x 12" x 1/8" sheet of black acrylic
- SPST 5V relay
- Perfboard
- 5" x 2.5" x 2" project box.
- SPST momentary pushbutton switch
- 10K resistor
- (x2) 9V battery snap
- (x2) M-type plug adapters
- Misc. long zip ties
- 16" x 2" x 1/4" aluminum extrusion
- 3-1/2" x 1/4 bolts
- (x6) 1/4 nuts
- Tea light
- Matches

Step 2: Cut a Cap

Picture of Cut a Cap

Cut around the stem of the pumpkin at an angle (with the knife slanted in towards the stem of the pumpkin)

After you are done cutting all the way around, remove the stem. This will serve as your lid later on.

Step 3: Gut It

Picture of Gut It

Remove the guts from the pumpkin. To start it should be easy simple to pull them out by hand, but this is going to quickly become too difficult.

Using a metal spoon or other scraping tool (I found a chisel works best) scrape the sides of the pumpkin and remove all of the slimy innards. The inside should be reasonably smooth and clean when it is done.

Step 4: Design a Face

Picture of Design a Face

Draw a face on a piece of paper and then cut it out and tape it to the pumpkin.

One thing to keep in mind is that the mouth needs to be large and about halfway up the pumpkin or the flames aren't going to be able to shoot out.

Step 5: Trace

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With a marker, trace the outline of the face onto the pumpkin and remove the paper.

Step 6: Cut

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Cut out the pumpkin's face. For the larger and more complicated shapes like the mouth, it help to cut it out in smaller pieces instead of trying to remove one large chunk from the pumpkin.

Step 7: Bend

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Make a mark about 6" from one of the edges of the aluminum extrusion.

Line up this mark with the edge of the workbench and clamp it between the workbench and something stiff and flat like a 2x4 or metal bar.

Grab the protruding edge firmly and push down until it is bent to 90 degrees. In doing so, you may want to push it slightly past 90 degrees as the aluminum tends to spring back a little when done.

Step 8: Brackets

Picture of Brackets

Download the following files for the motor mount and candle holder.

Use these files as cutting guides to cut the pieces out of 1/8" acrylic.

At times like these, having a laser cutter or using a laser cutter service comes in handy.

Step 9: Drill Holes

Picture of Drill Holes

Use the two mounts that you just cut out as drilling guides on the aluminum extrusion.

The motor mount should line up with the long edge of the extrusion and you should use a marker to mark all 4 corner holes.

The candle mount should be slightly backed off from the short edge. Make two marks for those holes as well.

When you are done, drill 1/4" holes through the aluminum using a drill press.

Step 10: Attach Things

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Stack the two motor mounts and align the motor atop it. Zip tie it all to the aluminum bracket.

Below it zip tie the small WD-40 can. The actuator from the motor should be aligned and touching the top of the can, but not yet pressing down firmly onto it.

Step 11: Candle Mount

Picture of Candle Mount

Insert the two bolts upwards through the bottom of the aluminum bracket. Fasten them in place with bolts.

Thread on another bolts onto each. Twist this about 3/4" down.

Place the bottom of the candle holder (the side without the large hole) onto the bolts. Then place the top candle holder bracket.

Fasten the whole thing in place by threading on another nut onto each.

Step 12: Battery Adapter

Picture of Battery Adapter

Solder the 9V battery snap to the M-type plug such that the red wire is connected to the tip and the black wire is connected to the barrel.

Don't forget to slip the plug's cover onto the wire before you solder.

Step 13: Program the Receiver

Picture of Program the Receiver

Open the SquidBee transmitter node and remove the Arduino from the XBee shield.

Change the power jumper on the Arduino to select USB power (if necessary).

Program the Arduino with the following code:

When done, disconnect the USB power, change the power selection jumper, and plug the XBee shield back in.

Step 14: Program the Transmitter

Picture of Program the Transmitter

The transmitter is a little bit trickier if you are using a SquidBee setup because it is lacking an ATMEGA chip.

First unplug the XBee shield.

If necessary, add and bootload and the chip.

Then, like the other board, change the power selection jumper to USB, and then upload the following code:
When you are done, unplug the USB, and reconnect the XBee shield. You will also need to swamp back the power jumpers on the Arduino.

Lastly, change both of the TX/RX jumpers on the XBee shield from USB to XBee.

Step 15: Switch

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Drill a 3/8" hole (or whatever is appropriate for your switch) in the side of your project enclosure.

Install the pushbutton switch.

Step 16: Antenna

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Install the antenna into the side of the enclosure opposite the switch. Be careful not to break the wire connecting the antenna to the XBee.

Step 17: Wire the Transmitter

Picture of Wire the Transmitter

Solder a wire to one leg of a 10K resistor. Solder the opposite end of this wire to one of the switch terminals.

Plug in the side of the resistor with the wire soldered to it into pin 2 of the Arduino. Connect the other end of the resistor to ground.

Solder a wire to the other terminal on the switch and connect this wire with 5V on the Arduino board.

Lastly, plug your 9V battery connector into the power socket on the Arduino board.

Step 18: Power

Picture of Power

Plug in a 9V battery to power up the transmitter.

Step 19: Case Closed

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Fasten shut the transmitter's case.

Step 20: Wire the Reciever

Picture of Wire the Reciever

Affix the relay to a small piece of perfboard.

Connect one of the relay's coils to ground on the Arduino board and the other to pin 3.

Attach 9V to one of the relay's load pins and a long red wire to the other. To get easy access to the 9V power source, I broke off the top of the 9V battery snap and soldered a wire directly to the +9V battery connector tab (notice the extra red wire coming from the 9V battery snap).

Attach an extra long black wire to ground.

Step 21: Put It Together

Picture of Put It Together

I lost the case for my SquidBee transmitter node (the pumpkin receiver) a long time ago. I find that a piece of black gaffers tape typically gets the job done.

I plugged in the 9V battery and passed the red and black wires through the hole in the side of the case neat-like.

Then, I slapped a piece of black tape on top and called it a day. This will be inside the pumpkin, so aesthetics don't matter quite as much.

Step 22: Wire the Motor

Picture of Wire the Motor

Wire the motor to the relay wires such that when the relay closes, the motor's actuator pushes down. In this case, red went to blue and black to green. It may be different for another motor.

Step 23: Put It in the Pumpkin

Picture of Put It in the Pumpkin

Place the whole contraption inside of the pumpkin.

Make sure that the battery is plugged in.

Also, make sure that the lid fits. If the lid does not lay flat, trim it appropriately to work.

Finally, it is a good idea to test to see if the the WD-40 sprays when the button on the transmitter is pressed down. It is easier and exponentially safer to debug this when there is no flame present.

Step 24: Candle

Picture of Candle

Once it is certain that everything is working as it should, it is time to add fire.

First off, find the transmitter. Make sure no one or nothing is pressing down on the button and it is somewhere safe.

Light a tea light and place it in the candle holder.

Step 25: Fire!

Picture of Fire!

Take a number of steps way back from the pumpkin and press the trigger on the transmitter. If all is well with the world, the jack-o'-lantern will blast a burst of hellfire out of its mouth.

Shock and awe all innocent bystanders. This is the stuff nightmares are made of.

All of that said... SERIOUSLY, DON'T MAKE THIS.


AnthonyH19 (author)2016-11-01

So the Door Lock Actuator spec is to 12V. Does this work well with the 9V supply?

randofo (author)AnthonyH192016-11-02

I don't know, but it likely should still work with 9V.

nearboston (author)2016-10-21

Since no one is going to build this I don't have to tell you not to swap out a can of engine starting spray (ether) for the WD-40. That would make a flame that is much more dangerous. DON'T DO IT!

AlecM7 (author)nearboston2016-10-21

Haha lol, what about carburetor cleaner? :D

Apxeon (author)2013-10-23

OMG your porch is made of wood though!

Chikpeas Brother (author)Apxeon2014-02-11

Wood isn't as flammable as most people think.

That's probably why they make wood stoves.

WildB (author)allangee2016-10-21

That's not how combustion works. To catch an object on fire, it has to be brought up to its ignition temperature for a long enough period of time to get that self sustaining reaction going.
A momentary burst of fire, unless the object has a very low ignition temperature, usually does not set things on fire. Most wood has an ignition temperature of 190-260°C - even decayed wood needs 150°C to ignite.
The flash point for WD40 is 49°C, which a tea light candle burns at a maximum of 1400°C - as you can see, it easily reaches the WD40s flash point for ignition. Once the hydrocarbons in the WD40 reaches flashpoint, they leave almost no residue of the fine particulates due to their aerosolized nature.
You might get some flash charring, but even that is likely with maintained wood.

allangee (author)WildB2016-10-21

Which, as I said, is why they can make stoves out of wood.

AlecM7 (author)allangee2016-10-21

Can you post a link to a picture of a wood stove?

allangee (author)AlecM72016-10-21

Here's a closeup shot.

AlecM7 (author)allangee2016-10-21

I don't see it

WildB (author)allangee2016-10-21

I went on the hunch you were being sarcastic, which is why the post explaining things.

BarryN2 (author)2016-10-21

I am waiting now for someone to build this, and then next some lawyer to file suit against this web site for posting these instructions after someone gets hurt. I have no doubt that some idiot will will build this and misuse it and someone somewhere is going to get hurt. It is not a case of if, it's a matter of when.

holla2040 (author)2016-10-21


rxima (author)2016-07-29

hahaha good idea

snowdrop1101 (author)2016-06-05

Nothing good will come except: Watching little children running around with smoke coming off of them like when Mario touches fire in Super Mario 64!

lime3D (author)2014-09-30

The WD40 formula has changed, and will no longer work for this. You might be able to find aerosol hair spray.

plundquist1 (author)lime3D2015-11-05

Ether will work

adam.verner.790 (author)2015-06-06

won't be better to put a spark generator in the pumpkin rather than candle?

mark.diaz.58118 (author)2015-04-21

Hmmm - bringing tricks back to Halloween. I laughed my ass off the second I saw this one!! I agree it's a bit... extreme but what a cool idea!!

Chikpeas Brother (author)2014-02-11

I made something very similar to this last halloween. I removed the pump mechanism from an electric weed sprayer, and secured it inside a jack o lantern. I also connected a gas tank of lighter fluid to the back of the pumpkin, and extended the battery pack by about ten feet and inside my house. I then placed an ordinary candle inside the jack o lantern, and sprayed flame by activating the pump from inside the house. Not exactly wireless, but you couldn't tell how it was powered.

The neat thing about this design was that the tank could be filled with any oother liquid such as water or fake blood. The effect was pretty cool.

picturelights1 (author)2013-10-16

Thanks for inspiring me. And i try this!

Mr. (author)2013-10-13

This is great and I'm sure you'll use it safely but pleases remember that many Halloween costumes are very flammable and you will seriously injure someone if you light them on fire.

kjlpdx (author)2013-10-12

easiest would be a wire and switch assuming you're smart enough not to want to fire this without being present and watching. also no stray signals could set it off.

astral_mage (author)2013-09-19

easier idea is use 1 of those motion censored air freshners. but angle the tube down ward. an out the front over the candle. uill get the same result. w/o going thro the same programing stuff

wusupworld (author)2013-07-14

to late making it hahahahah take that kids who trash my house i'l use a tripwire hahaah

dennist1 (author)2013-05-09

With arduino and a distance sensor, this could make quite a security system! Don't try this at home or anywhere else though - the idea would make this even more dangerous than it already is!

dennist1 (author)2013-05-09

Neat idea, for sure ... but Arduino is a bit overkill. All ya gotta do is power up the actuator. Even real fancy, use a 555 and the relay to limit the on time (to save baking the pumpkin).

baited (author)2013-03-29

This is a cool project. You may want to place a diode across the coil on the relay to protect the electronics. And depending on the relay a transistor may be needed to handle the current.

JensonBut (author)2013-01-25

I'm rating most of your i'bles 5! Awesome stuff, affordable and compact.

awesome! i wish i had known about this far enough in advance of october 31st to construct it. seems a fairly simple idea just having a remote controllled aerosol can to spray over a flame. i would like to know if there is an easier and cheaper way to set up a remote control system for other projects, i do not have an arduino but surely i can make a transmitter/receiver from basic electronic components or rewiring a remote control car.

RC car would be my suggestion.

mangomango (author)2012-09-07

I'm working on my own creation for this halloween and i was wondering if you had problems with your candle getting blown out?

LiamOSM (author)mangomango2012-10-30

I don't think they actually made this, remember?

stephenham5511 (author)2012-10-28

tooo awesome!

canida (author)2011-10-25

Sweet! Now all you need is a motion/proximity sensor...

kmiller29 (author)canida2012-10-28

a few simple things for a motion prox sensor is to get a cheap motion light from menards or lowes or some store like that and add a relay from 120vac down to what ever your control voltage is this will give you (in test mode) a 5-15 second trip on a 555 ic timer

randofo (author)canida2011-10-25

Maybe next year...

astroboy907 (author)randofo2011-11-03

lol... +1 for no warning :)

Alpvax (author)canida2011-10-30

The problem being you then have to warn people not to get too close... have it inside a cage for example, so the flames won't reach the person

ElectroFlex (author)2012-10-14

Not that I'm trying to make one of these or anything... But, if I were, theoretically, and the actuator was not, hypothetically, not strong enough to press the spray nozzle, how would I make it? Should more battery power do the trick?

randofo (author)ElectroFlex2012-10-16

The motor I use is supposed to run of 12V. Hypothetically... A little more voltage / current, would not hurt.

dlchambers (author)2012-10-06

Pretty cool, but the Arduino/XBee is overly complex/expensive.
A 1-channel RF remote like this would be much easier/cheaper/faster:

Thundermoon99 (author)2012-09-23

this is probobly the most epic pumkin i have ever seen.... ever

thecrazymagnetman (author)2012-06-14

i am geussing you don't get many trick or treaters huh

tinker234 (author)2012-02-21

wow that be so funny to make it work at a angel above trick or tr eater and blow flames

Annix15 (author)2011-12-12

LOL, this is awesome, what if someone passed by and the pumpkin starting throwing fire out of its mouth!!

Dude who is passing by: pit pat pit pat, walks up stairs to knocks on door*
Flame throwing Pumpkin: Starts breathing fire out*
Dude: AHHHHHH, jumps back and falls of patio*
Flame throwing pumpkin: MWHAHAHAHAHA

black hole (author)2011-11-08

This is hilarious! You've got my vote.

bernynhel (author)2011-11-05

Cool! I did the same thing with my articulated cardboard skeleton on the front door of my pad using a flex line to extend the natural gas from behind my kitchen range/oven to the peephole on the door - motion detector > solenoid > flex-line to nozzle from a fireplace ceramic log kit to concentrate/direct flame at peephole. Adjusting the gas flow at the source resulted in flame range from the answer to "Got a light?" all the way to the center line of the street in front of the house! There were 18 of those nozzles to share the gas feed in the fireplace kit I cannibalized the nozzle from so... chose halfway between front door and the sidewalk, and, being self contained with unlimited fuel supply, you can just turn it on, cross your fingers that the Gas Co delivers @ constant pressure and forget about it!

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Bio: My name is Randy and I am a Community Manager in these here parts. In a previously life I had founded and run the Instructables ... More »
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