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

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

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

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

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

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

Step 6: Cut

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

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

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

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

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

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

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

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:

//Flamethrowing Jack-O'-Lantern Receiver code
//Copyleft 2011

int sentDat;

void setup() {
  Serial.begin(9600);   
  pinMode(3, OUTPUT); 
}

void loop() {
  if (Serial.available() > 0) {
	sentDat = Serial.read(); 

	if(sentDat == 'h'){
          //activate the pumpkin for one second and then stop
  	  digitalWrite(3, HIGH);
          delay(1000);
          digitalWrite(3, LOW);
	}
  }
}

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

Step 14: 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:

/*
  
  Flamethrowing Jack-O'-Lantern Trigger code
  
  Based on Button example code
  http://www.arduino.cc/en/Tutorial/Button
  created 2005
  by DojoDave <http://www.0j0.org>
  modified 28 Oct 2010
  by Tom Igoe
 
 The circuit:
 * pushbutton attached to pin 2 from +5V
 * 10K resistor attached to pin 2 from ground
 
 This code is in the public domain.
 
 */

// constants won't change. They're used here to 
// set pin numbers:
const int buttonPin = 2;     // the number of the pushbutton pin
const int ledPin =  13;      // the number of the LED pin

// variables will change:
int buttonState = 0;         // variable for reading the pushbutton status

void setup() {
  // initialize serial communication:
  Serial.begin(9600); 
  // initialize the LED pin as an output:
  pinMode(ledPin, OUTPUT);      
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin, INPUT);     
}

void loop(){
  // read the state of the pushbutton value:
  buttonState = digitalRead(buttonPin);

  // check if the pushbutton is pressed.
  // if it is, the buttonState is HIGH:
  if (buttonState == HIGH) {     
    // turn LED on:    
    digitalWrite(ledPin, HIGH); 
    //transmit a High command to the pumpkin and delay a second so that it does not recieve more than one command
    //per button press
    Serial.println('h');
    delay(1000); 
  } 
  else {
    // turn LED off:
    digitalWrite(ledPin, LOW); 
  }
}

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

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

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

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

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

Step 19: Case closed

Fasten shut the transmitter's case.

Step 20: 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

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

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

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

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!

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.

Comments

[dennist1]

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]

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]

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.

[instructamaker]

You could havee used the ruler :D

[JensonBut]

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

[resistanceisfutileiflessthan1ohm]

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.

[randofo]

RC car would be my suggestion.

[mangomango]

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

[Liam.great98]

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

[stephenham5511]

tooo awesome!

[canida]

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

[kmiller29]

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

[Alpvax]

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

[randofo]

Maybe next year...

[astroboy907]

lol... +1 for no warning :)

[ElectroFlex]

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]

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

[dlchambers]

Pretty cool, but the Arduino/XBee is overly complex/expensive.
A 1-channel RF remote like this would be much easier/cheaper/faster:
http://www.lightobject.com/Multi-function-1CH-RF-with-water-proof-remote-control-P702.aspx

[Thundermoon99]

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

[thecrazymagnetman]

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

[tinker234]

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

[Lego Manic]

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]

This is hilarious! You've got my vote.

[bernynhel]

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!

[vinnyjojo]

Awesome as always, Randofo. Keep em' coming

[nspirit]

I WON'T ring your home for sure XD

[tha_jaker]

wow........ not much else to say......

[s00500]

BUILTED XD


But i used servo and a 555 timer ic another remote and a lever to trigger
great project

[ytashi]

OWH MY GAWD!!!! THIS IS SO DAMN COOL! now i want like a DOZEN? hehehe!

[tgray1]

Pretty impressive. Assuming that I don't make one of these, how long would the can of WD40 last? (How many 1-second bursts, say)

[bassemads]

I would say about 100-200. I don't know exactly how large the can is though.

[astroboy907]

hey randofo, me again :) what is your video edit software? I just use iMovie but I have final cut pro (which I dont exactly know how to use...)

[randofo]

I'm sort of a barbarian in terms of video editing. I typically use Quicktime Pro and Photoshop.

[chicopluma]

insane jajaja

[Mechanic2011]

I got to get this made for Halloween.
This should keep the kids from grabbing my pumpkin and smashing it in the street !!

[PokemonInterpreter]

hey, you're right! I usually go on my roof with an airsoft sniper rifle (i shoot at their feet) with four other friends on gate night and play what we call "tower defense". chase off pranksters without taking damage to property. I start at 8 PM and we go in shifts until 6 am. We even have snacks and refreshments in a box up there for the snipers. This is a secondary defense we will use

[Electronics Man]

WOW awsome job!

[User1]

Thanks for warning me! I didn't make one. :-)

They'd probably just turn the thing around, around here anyways.

[mangomango]

i love this idea man, great 'ible! im currently working on a flamethrower for my RC car using the innerds of a nerf thunderstorm and i'll probably use your transmiter/reciever idea now, thanks alot!

[ed.alexander]

If you don't want on demand You could probably just use an air freshener glade has one, has motion sensor and timer. Just need to make sure the can fits.

Blast wouldn't be as long, but steps would be much easier.

More dangerous and would need to put completely away from access (like on roof) cause it will go off on it's own.