Introduction: Jack-o'-lantern on Fire ('Propane Pumpkin')
Jack-o'-lantern on Fire
Nothing is more mesmerizing than fire. So what could be better than a Jack-o'-lantern on fire! The dancing flames just add to the atmosphere and mystery surrounding Halloween. This instructable will show you how to build your own 'propane pumpkin'.
There have been several instructables published over the years that use a kerosene soaked toilet paper roll as fuel inside a jack-o'-lantern, and they look really cool. However, this project, unlike the others, uses propane gas to fuel the flames.
This has several advantages:
1) No messy flammable liquids to store, spill or clean up,
2) The burn time in not limited by the fuel in the pumpkin. This project will run for hours and hours on a 20lb propane tank and not just the 45 minutes as many of the kerosene fueled jack-o'-lanterns do. No need to refuel during your festivities.
3) The flame is adjustable so that you can have it burning at a low 'simmer' or crank it up to a 'blow torch'!
Let's be smart, we are playing with FIRE - Let's not get burned.... Or burn anything down, or catch anything or anyone on fire.... etc. OK?!
Of course with propane gas you need to be careful to not allow it to collect (propane is heavier than air and will seek to collect in low lying areas) or mix with air to become an explosive atmosphere or displace air and create an environment without sufficient oxygen to breath (suffocation/asphyxiation).
CAUTION - This is a project utilizing fire! This and other open flames need to be kept away from flammable materials and people need to be physically kept away from the flame. It may be necessary to erect barriers, locate the flame out of reach, or use other means to prevent people from coming near it. Consideration should be given to the determination of children to come near the flame and plan accordingly to prevent their access. The open flame should be supervised at all times by a competent adult that can quickly turn off the fuel source. When locating this flaming display you need to consider the potential flame size when 'on full' and wind blowing the flame toward or onto flammable materials. Also consider the radiant heat projected from the flames - Adjacent surfaces can get hot and ignite. Fire fighting materials (water, fire extinguisher, water hose, etc.) should be readily available.
Making a mistake can result in property damage, personal harm or even death to yourself or others. You need to be familiar with fire, propane gas and its hazards. If you are not knowledgeable and comfortable with this project do not attempt it. You take full responsibility for the project you build/assemble. I may be taking risks that are acceptable to me, but may not be acceptable for you or your circumstances. Build/assemble at your own risk. If you do not understand or have questions consult a professional. Sorry for the disclaimer, but if you burn something down or kill yourself or someone else it's your own fault, not mine. :-)
Step 1: Supplies
Jack-o-Lantern (Willing to be sacrificed to the flames) - Use a real carved pumpkin, not a plastic decoration!
Propane Regulator, KING KOOKER Model# 00502 (10psi, Not inches of water output)*
20 ft 1/4" OD vinyl tubing
2 ft. 1/4" copper tubing. Use at least 2 feet so that heat can't transfer from the burner to the vinyl tubing.
Tuna fish can
Brass hose barb 3/16" ID x 1/4" MIP
20 lb propane tank
Tea Light Candle
*Many gas regulators output gas at very low pressure, measuring the pressure by the column of water that the gas pressure can lift. Hence, the pressure rating in "inches of water". This is a much higher output regulator that can output gas at 10 pounds per square inch pressure.
Awl or drill
Pumpkin carving 'utensils'
Match or lighter
An over abundance of caution, and appropriate fire fighting materials as noted in the text.
Step 2: Make Your Burner
To give the flame some shape and to prevent the flame from shooting out of the front of the jack-o'-lantern we need to create some type of burner. Although this is a crude contraption, it does the job. It directs the flame upward and gives it a bit of 'swirl'.
Take an empty clean tuna fish can and use an awl or drill to make a hole in the sidewall near the bottom of the can. The copper tubing (gas pipe) enters at this location and should be tangent to the perimeter of the can so that the gas jet spins around the bottom of the can before exiting upward. Use at least 2 feet of copper tubing to insure that the heat from the burner does not get transmitted to the vinyl tubing and melt it.
Take the fine steel wire and secure the copper gas tubing to the inside of the tuna fish can so that the copper tubing cannot slip out of the can. We don't want the copper tubing (gas pipe) to spray gas anywhere except inside the tuna fish can otherwise we might end up with a jet of fire shooting out of the front of the pumpkin.
Make a hole in the back of the jack-o'-lantern and thread the copper tubing (gas pipe) though it. You might have to bend the copper tubing slightly to get the burner assembly (tuna can) into the jack-o'-lantern.
Step 3: Assemble the System
Locate your 'Jack-o'-lantern on Fire' on a non-flammable surface in a location that will keep the flames away from people and flammable materials. Keep the 20lb propane tank well away from the flames and it an area that can be quickly accessed should the flames need to be extinguished.
Be sure to run the vinyl tubing carrying the propane gas as far away from the flames and radiant heat as possible.
Apply several layers of teflon tape to the brass barb and thread it into the regulator outlet. Tighten securely.
The tubing pushes onto the brass barb at the regulator and fits over the end of the 1/4" copper tubing (gas pipe) at the pumpkin, push the tubing onto the copper tubing about a 1/4".
Step 4: Light Your 'Jack-o'-lantern on Fire'
Make sure the propane tank valve is turned off - fully clockwise.
Connect the regulator to the tank. Insure that the regulator valve knob it turned counter-clockwise as much as possible (off position for this type of regulator).
With everyone far from the jack-o'-lantern remove the top of the pumpkin and place a tea light next to the burner(tuna fish can) and light it. You must have a source of ignition available immediately when the gas exits the copper tubing. If you try to light the burner with a match or lighter, gas can build up and create a fireball and you may be injured. Always have a tea light burning next to the burner when turning on the propane gas.
Turn on the propane by opening the propane tank valve by turning it counter-clockwise. Check your connections with soapy water and look for bubbles of leaking gas. Correct any leaks.
Turn the gas on by turning the regulator knob clockwise. This is opposite of what you would expect for a valve, but think of it as a 'volume control', so you turn it clock-wise to make the flame larger. Turn the valve counter-clockwise to decrease the flame size or to extinguish the flame. If you use a different regulator make sure you know how it works before lighting your jack-o'-lantern.
Always remember to turn the propane tank valve off (clockwise) when not in use.
Step 5: Let the Fire Burn!
Have fun adjusting the flame height and enjoy the dancing flames. Remember that the 'jack-o'-lantern on fire' should be supervised at all times by an adult and not be left unattended at any time.
After some time the jack-o'-lantern will dry out enough to burn and the pumpkin will start to deteriorate.
Take care that the pumpkin does not deteriorate to the point that it will fall into the burner or create hazardous flame patterns.
Have fun and SAFELY enjoy your 'Jack-o'-lantern on Fire'!