Instructables

Step 6:

It's an amazing feeling when your creation first gets lift and starts to take off.

At this stage, there's about ten thousand things that could go wrong. Carefully think everything through before you actually do it.

I tied some thread to mine so I could fly it inside our warehouse without it getting away and setting the place on fire.

It will drip a lot of hot wax, so keep it over the cardboard if possible. Also, if you let the candles burn all the way down, the balsa will catch on fire. I am currently experimenting with other types of candles to prevent this.

Fly safe!
imrational2 years ago
I use to make these out of tissue paper and balsa (with an aluminum foil cup to hold the fuel) when doing science lessons for elementary school kids. For the fuel, I'd recommend melting some vaseline and soaking a cottonball in it. Then put the cottonball in your fuel chamber/gondola. Inflate the balloon with a hair dryer and then light your cotton ball.
flamesami3 years ago
hmm...maybe you could make a "kid-safe", indoor version....
If you substituted the candles for a VERY small weight, and used a non-attached hair-dryer as a heat source, you could have several on the go at once, with no fire hazard...not as fun without fire though...
wbsbadboy5 years ago
A word to the wise here. I think it was around 1989 when a close friend was launching these about once a week or so just to hear the reaction on his police scanner. Well one night he launched one and it started a fire on a wood shake shingle roof about a mile away. He had no idea that this had happened as he didn't listen to the fire department frequencies. Just the police. Two more launches and they had his general area down to a three block radius. Two weeks later he was arrested and charged with Arson. He was sentenced to 4 years in prison. Police said that he was lucky that no one was killed or injured. If someone would have been killed he would have faced premeditated murder charges. If injured he would have faced attempted murder charges. Please do not launch these things as "UFOs". Keep them teathered or inside. Here in California it is illegal to release anything that is burning that is not short lived (like a bottle rocket or fireworks that leave the ground). These balloons are easily carried miles away still burning. If you are caught you could face up to a year in jail, and/or fines up to 5,000.00 for the first offence. Be Safe, Be Sure, and Be Happy Best, Smitty
haha wow thanks for the info
I recently got inrested in rigid zepplins, and wanted to build an RC non-rigid blimp< however, found myself lacking any helium. I figured i coul make a mini hot air balloon and put RC fans on it... i would have a flap controled by a servo to redirect heat from the flame to lift of lower the balloon...
Nykus794 years ago
Look! It's Balloon boy!
Probably not a good idea, but maybe not.. If your baloon is big enough and you use a material not so suceptible to heat how about experimenting with something like a warning flare? Of course your balloon is going top have to be much bigger than what is pictured here and flares do give of ash and embers.. Another idea if you have a big enough balooon is how about a semi-remote fuel source from the ground using a very thin plastic tube? That way you can cut off the fuel source and heat when needed. Or with micro electronics I'm sure someone could figure a way to use a model airplane remote controller to control a heat source from the ground and maybe even a remote control vent to let heat escape instantly in the event of a run away wind gust carrying your flying arson package over a crowded populated area...just a thought. I'm not smart enough to do the details, but the ideas i can cook up all day long. ;)
SPININSPUR5 years ago
what about an oil lamp wick with wicks on the the long axis for more flame area and a contained tank for fuel?not sure right now what kind of tank.suggestions?
TJH545 years ago
I did a similar hot air balloon in High School. I used a thin plastic trash bag, Four single strands of copper wire taken from speaker wire. I used aluminum foil to make a gondola to hold a small amount of sterno for the fuel.
TechnoDave9 years ago
I just found this site today but remarkably I made one of these just yesterday! I use dry cleaning bags but the principle is the same. I also tie fishing line to mine so they don't fly off and start a forest or house fire. When I was a kid we made one that flew forever - people called in to the radio station saying it was a UFO - very funny.
Made a bunch of these when in college. We'd use colored cellophane, a different color on each side (4 or 6) and a small vent to one side at the top to encourage them to rotate slowly while flying. On a cold clear winter's night the UFO calls would go on for hours... When starting them out, use a hair dryer for the initial inflation.
Commsman5 years ago
Try inflating the balloon using a hair dryer first - then it will only need a small slow burning device to keep it aloft.
Ssiatha5 years ago
could I suggest some alfoil wrapped cardboard under the candles? it'd stop wax drips and you need not worry about candles burning down. attach /w glue obviousley
I saw this done before from the American Boys Handy Book, by Neally Croft just different materials. I like the new materials being used. BIG Caution is Balloons can start fires easly, carefull where you fly them!
modded dollar store lighters would work i think. take off the metal cover and set the flame real high. tape it to the frame, tape the button down, then light it with another lighter. light fuel source and would go for a while. not very wind resistant tho, and probably a fire hazard......
dbguettl5 years ago
I remember doing this years ago. We took a slightly different approach. 1. We used a really big trash bag made from very thin plastic. I don't remember the size or the thickness. 2. We took some really thin music wire and made an x. 3. Then we cut the bottom off of a coke can and mounted it in the center of the x. We mounted it with copper wire. You have to mount it so the bottom of the can faces up to make a "bowl" for the fuel. 4. Using tape, we taped the music wire/coke can assembly to the bottom of the trash bag. (similar to how you used he balsa 5. For the fuel, we made a tee pee with some scrap balsa, superglued it in place, and doused it with model airplane fuel (this just happened to be what we had lying around). Other flamable fluid such as alcohol should work too. 6. We had to light a piece of wood and hold it under the bag to pre-inflate the bag with hot air, then we set off the fuel/wood and let it go. It was great to do in the evenings when the wind was calm. It would fly 100-200 feet before coming down. Just be careful. On one flight, it got knocked around by a gust of wind and the fuel fell out and fell to the ground. I've always wanted to do it again and try using sterno as fuel.
saum5 years ago
i wanted to ask u if i could put a small box at the bootom. like a real hot air balloon
5Toes6 years ago
So I was just thinking... You could make a good heat source using gasoline. You could add two tanks to the frame.. that are small. So about 10 fluid ounces all together. Add a fuel line to each and make a it very small, so the flame wont get out of control, or too big!!! Take the two fuel lines, and add a small flame resistant plate above. The plate should be about 2 inches in diameter. Add a flame source to the middle of this plate and the gasoline lines directly under it. With some experimentation the tubes with gas should act much like a lighter!!
aiden1200007 years ago
in the british army (i dont know about others) they use hexi blocks, they are like small bricks of soap. They burn for a long time http://www.surplusandadventure.com/shopscr2155.html
El-Butchio7 years ago
if you made the baloon bigger it would be able to carry much heavier weights, as long as you incresed the heat produced. this is easily done by soaking cotton wool in spirits or meths, however i do not know how this could be efficiently contained without embers from the cotton floating upwards into the baloon and burning a hole in it. Also, DO NOT use petrol as fuel in this projest as it has a tendency to make the air too hot for the balloon to withstand and melts it, causing burning petrol to spill onto you from above which may hurt you a bit.
Apache8 years ago
How about tinfoil on the balsa wood to keep it from burning
ewilhelm (author)  Apache8 years ago
Foil might do the trick, although the aluminum pie plate I mentioned in response to robotix, I think, works better.
robotix8 years ago
This is cool, but for the dripping wax and burning the balsa wood couldn't you just use a tea candle in the little medal cups or glass candles?
ewilhelm (author)  robotix8 years ago
I've experimented with tea candles, but they're simply too heavy. You really need a high flame area / total candle area to make this work. I tried putting multiple wicks into a single tea candle, but that really didn't work all that well because the wax would melt and the wick fell over. Putting birthday candles in a small aluminum pie plate has worked pretty well to contain the dripping wax. I'll post my current design when I get a chance.
it might not generate enough heat or it might be too heavy
gn0stik8 years ago
Dollar store hula hoop for the frame would work great with a bigger bag(due to the weight. but the painters plastic bag is nice, as big light bags are hard to come by. Little fishing string and a small weight would be good for ballast as well. And as someone else mentioned, foil for fire prevention. Also filling it with a hairdryer, or heat gun ahead of time would allow you to use less heat to keep it going, and preserve your candle life. Then you could use tea lights or say goodbye to all your wife's party lite bull-crap.
qolque8 years ago
I did about a dozen of these when I was a boy(learned at a scout meeting!). Dry cleaner bags are very thin (and you just get the old ones from neighbors for free), you just need to melt the holes on top with a hot object. (Don't use Mom's iron!) We used simple drinking straws for the frame. Just put the straws in an X and spliced enough straws to hot the bottom of the bag open. You carefully cut holes in the straws to hold the birthday candles. We just used Scotch tape to hold the straws in place. Then, you heat the bag with other candles (or a narrow flame backpaking stove). Don't light the birthday candles till the ballon is starting to tug. Once it is going to go up, you light the small ones, they last around 5 min. That's plenty of time for your balloon to outdistance you. We only recovered 2 of them. They work best once it is cold enough for a jacket. (Also heard that pencilpoint holes poked about 2/3 up help to stabilize, but haven't tried that myself)
rusty13jr8 years ago
I have built these before...but I use solid core 12 gauge wire for the frame and I hang three or more tealights in the middle. I find that bags of 5x6 or greater dimensions can hold more than ten candles.
sam8 years ago
i did this as a scout.. not long ago!! it works really well outside on a COLD day.. we used to do it at winter camps. ours had cotton soaked in alcohol. we also used fishing line.. great project for pyro scouts!!!!
KidByte8 years ago
When I was a kid, my grandfather told me he made one of paper and sticks. He used beeswax and kerosene (make a ball) and lit it for heat. It got away from him and burned up a neighbor's dry grass field! ah ha ha! I made one of tissue paper "gores" glued together, a small wire hoop for the opening and a tin with toliet paper and rubbing alcohol for heat. Worked great!