Guide to Flammable Aerosols

This is Jake's unofficially official guide to all flammable substances that come out of a can. Think cooking spray, deodorant, engine starter, hairspray, etc. What they are, how to tell if they are flammable or not, flame size, danger factor, whether they'll work to power your spud gun, and all that other good stuff for my pyromaniac friends.

Note: I am not the complete expert on all these substances, and I have not had the chance to test yet everything that's out there. I will be updating this list as I experiment with more, so I'd love your recommendations.

Ready or not, here we go.

1. Hairspray (the classic)

As far as flamethrowers go, hairspray has an average to small flame.  

I'll also mention an interesting thing I've noticed about hairspray; it seems to have a flammability shelf-life of sorts. I don't understand it, and I may be mistaken, but all the cans I've used have lost their potency after about a year of sitting on the shelf. They aren't nearly as powerful, and they don't have much of a flame anymore. Strange. 

Is it good for Spud Guns?

This is the classic for powering tater guns. It works well, and is powerful. The only downside to its use is the sticky residue it leaves behind. That nasty sticky stuff has annoying tendency to glue the screw cap on tight as heck. If you don't clean your threads before putting it away after each use, you will need a really big wrench and a whole ton of elbow grease to get it off again. Other than that, the results are generally satisfactory, although the power tends to vary a little between brands. Aqua-Net is the brand I usually use. 

2. Spray Deodorant

Another classic. If I had a buck for every prank video on YouTube involving a can of Axe, a lighter, and a couple of blonde teenagers, dang, I could build some really awesome stuff. It works very well, with a large flame.

Is it good for Spud Guns?

Yes. It works great of spud guns. a tad more powerful than hairspray, but without the glue effect.

3. Spray Paint
Spray paint is great. Very flammable, good flame size. Danger factor is average. Not much to say here. 

Metallic Silver spray paint:

Burn is the same as regular spray paint, except it has flecks of metal in it that when burned make a cool sparkling effect. I have found that the textured kind makes more sparks (the camera doesn't capture the effect unfortunately).

Metallic Gold spray paint:

Burns with an incredible blue/green flame, which is absolutely awesome. It also puts off a bit of white smoke. This is a really awesome reaction. The blue/green fire is very cool. It also has the sparkling effect like the silver, due to the flecks of metal in it. Why green flames? Probably because of copper  alloy in the paint, used to give it the gold color. Danger factor? About the same as regular spray paint. I would be careful about breathing the fumes created by any of these. Spray paint is bad enough to breath on its own, and burning it won't improve that.

Is it good for Spud Guns?

As far as performance goes spray paint is very good, better than hairspray. However it is after all paint, and using it in my spud gun means the combustion chamber will have a new look. If you don't mind painting up your gun, then I suppose you could use it. I don't. You also may need to be careful as many spray paints have chemicals like acetone in them, which can probably eat away the PVC after a while.

4. WD-40 

I've read that the company changed what was in it recently and it's less flammable than it was previous. In my experience it's about average, but does not put out as fine of a spray, and the flame shape reflects that. Flame size is similar to spray paint, darker in color, and is very uniquely shaped. It puts off a bit of smoke when burned, and an educated guess would say that you probably shouldn't breath it. There is also a large bit of unburned waste spraying off into the air when burned. Danger factor? Average.

Is it good for Spud Guns?

I would say no. It would probably work in a pinch, but due to the fast shooting nozzle, and not a very fine spray (after all, this is designed to shoot large amounts of oil onto things, not to put out a wellatomized mist), as well as a good amount of waste, I don't think you would get much success.

5. Silicone Lubricating Spray

Similar to WD-40 in that it puts off a lot of waste. Flames are hot, bright yellow/orange with a large spread but very short range, due to the throw of the nozzle. Danger factor is a little higher than normal, because the spray goes wide, and doesn't have much range, so the fire is closer to the can than with the others. It feels a bit hotter than usual as well (which may just be because the flames are closer to my hand). I prefer to wear gloves with this one.

Is it good for Spud Guns?

Well, I don't use it. Would it work? Yes. It does work. However it simply has too much waste for my taste, and silicone spray has an annoying way of getting everywhere, due to the very wide, very fine spray. The combustion chamber will be coated with large amounts of silicon oil, as well as your hands, your clothes, and anything else near you.

6. Cooking Spray

You'd suppose a spray you use all the time within close proximity to your stove would be designed to be less flammable. Apparently not. I've personally tested 4 variants of this stuff, and they are all very impressive flame-throwers. As you can see from the picture. Flame size is a notch larger than spray paint.

Is it good for Spud Guns?

Yes, it works great for spud guns. Much like silicone spray though, it puts off quite a bit of waste. If you're fine with that, then go ahead. 

7. Wasp/Hornet Killer

Will not burn at all. I have tried every can I've got my hands on with zero success. It is not flammable in the least.

Is it good for Spud Guns?

Not applicable.

8. Engine Starter

Absolutely epic. This is the most flammable stuff that comes out of a can. It puts out 5 foot flames easy. Danger factor? On a scale of 1-10, this would be a 12. Very dangerous, extremely fast burning, and a considerably hot burn temperature. Remember, this stuff is used to help old rusty engines get going again when regular gasoline apparently isn't cutting it. In other words, this is more flammable, starts easier, burns faster, and burns hotter than gasoline. So, yeah. It's dangerous. You need to exercise extreme caution when using this stuff. Unlike the other sprays in this list, Engine Starter is not just flammable while in the air. It's every bit as dangerous on the ground. While this makes it a very cool thing to play with, (all the fun of gas in a nice easy to use portable spray can), it also gives it a new level of danger. With any of the other sprays, when suspended in the air they burn rapidly, but when that spray falls on the ground they no longer burn, as they aren't really flammable unless in the air exposed to oxygen on all sides. That makes them (relatively) safe to use. Not so with this stuff. On the ground it acts just like gasoline. Be careful.

Is it good for Spud Guns?

Don't risk it. This stuff is simply too volatile. Think gasoline in a spray can. You would not use gas in your potato cannon. Don't use this either. Not to mention that as a petroleum product similar to gasoline, there is a pretty good chance it would start eating through the polyvinyl-chloride, turning your combustion chamber into a gooey flaming (and probably toxic) mess.

9. Propane

Once again, not exactly an aerosol, however in a post in which I am discussing flamethrower fuel and spud gun propellant it simply must be mentioned. It's very flammable, easy to use, and with the proper setup makes for an excellent flamethrower. In the picture above I am using it in what I call my propane gun. 

Is it good for Spud Guns?

Yes it is. I have recently began to use it in my marble guns actually, and I've had very good success. I really love the fact that there is absolutely no residue left over after firing, and since it's a gas, I find it easier to use. 

10. Butane

Butane is very similar to propane. Flame size and burn are practically identical. The main difference (from an unscientific standpoint) is that propane is stored under much higher pressure.

Is it good for Spud Guns?

Same as propane, if you can figure out a way to get it from the can to your combustion chamber. Because butane is lighter fuel, the cans have a nozzle specifically designed to be inserted into a lighter, and don't have the nice spray nozzle that the others do. You'd have to rig some kind of adapter.

11. Polyurethane/Lacquer Spray

Flame size is about the same as spray paint, but because it is a wood finisher, they have a slightly different shaped spray nozzle, which in turn makes a different shaped flame. As you can see, this flame is shorter and taller than many of the others.

Is it good for Spud Guns?

For the same reasons as spray paint, I wouldn't use it. Otherwise I'm sure it would work great.

And that's about all I have so far.

How do I Tell if This Stuff Will be Flammable?

Obviously, the best way is to just grab a lighter and light it up. Nothing like seeing it in action. However, there is going to be a lot of times when you need to tell if a certain brand of, say, Hairspray will produce a good exothermic reaction. You can't, after all, just light it up in the aisle at Walmart. (Well, I wouldn't recommend it.) You will need to be able to tell from the label whether or not it will light up in flames, just smell really bad (adding insult to injury). Otherwise you'll waste a lot of money on not-so-cool un-flammable aerosols.

Here are some things to look for:

First of all, look at the warning labels. If its flammable on a dangerous level, the can will say so. 

Another thing to mention would be not to go with 'natural' junk. For flamethrower purposes, the more toxic it is, the better. You will notice on just about all of these products that there are warnings about ingesting it, inhaling it, getting it on your skin, in your eyes, etc. As a general rule of thumb, the more flammable something is, the more dangerous it is for your health. If you see a can of something marked 'natural', my advice would be to stay far, far away.

The other thing is, quite obviously, the ingredients. If you know what substances are flammable, then you'll know a spray that contains it has a good chance of being flammable too. For instance, I know that acetone is highly flammable. The label of this can of spray paint says it contains acetone. Thus, I know the spray paint has a very good chance of spraying satisfactory fireballs. Alcohol is also very flammable, and is an ingredient found on the label of just about every can of hairspray out there. Another thing to look for is butane or propane, which are often the propellent gases for these products (as demonstrated by this can of deodorant). Other than those things, really you just have to test them.

If you guys think of any others I should test, by all means let me know. I'd love to add to this post, and perhaps make a part 2 of the video.

Football Mortar

I'm too tired of typing to put together much of an introduction to this one, so I'll just get right to the point.

I built a Football Mortar.

You know what that is, right? A Mortar? That shoots Footballs? No, not mortar like bricks and mortar, like military mortar. Heavy artillery mortar. Army man mortar. You still don't know what I'm talking about, do you? (sigh) I'll have to explain.

A Mortar is a piece of military artillery which fires a projectile (usually an explosive charge) at a very high trajectory for shorter distances. For going over walls and the like. In comparison, a cannon fires a projectile for longer distances at a low trajectory, for bombarding walls and such. 

And a howitzer fires its charge at a trajectory between the two. Just a bonus fact. (no charge)

I made one that shoots footballs. Talk about a fun opening kickoff! 

This is actually a rather simple project, it only took me an hour or so to complete, and in my usual style is constructed completely out of trash. The only thing you need is duct tape. Lots of duct tape. And lighter fluid. Lots of lighter fluid. And a lighter. A long lighter. Or better yet, a propane torch. And several old empty paint cans. Or giant soup cans. Or giant bean cans. Or giant chili cans. Or--well, you get the idea. Something big enough to fit a football. Actually, the paint cans were a tad too big for the football, which is why I wrapped tape around it, to make it fit snugly. 

You can get a pretty good idea of the construction of the mortar by looking at my drawing of it below. As you can see, the mortar is made of four paint cans duct taped together, making four sections, the top two being the barrel. There is a baffle between both the first and second sections, and the second and third sections; which create the combustion chamber, and are the key to the mortar's success. The baffles are made out of the paint can's lids, with holes punched in a circular pattern around them. At the bottom of the first section, there is a hole punched in the paint can, which is the touchhole and the place where the fuel is loaded. And of course, I couldn't resist stenciling DANGER on it in giant orange letters. 

To fire the mortar I first slide the football down the barrel, ensuring that it fits tightly so as little gas escapes as possible. I then squirt a liberal amount of lighter fluid into the combustion chamber through the touchhole, and then shake the mortar around, turning it this way and that, up and down, spinning it around, etc. The point is to vaporize the lighter fluid and spread it through both chambers. It is rather difficult to get the right combinination of fuel to air in the chamber, so my shots vary in power. When I feel confident that I have gotten the fuel vaporized enough and spread throughout the chamber evenly, (or when my arms get too tired to shake it anymore) I prop it up at a sharp angle, cover my ears and apply the flame to the touchhole. 

Boom!!! 

There follows a deafening bang, and the mortar is thrown back several feet. I quickly look up into the sky, to see the football sailing high through the air, to land nearly three hundred feet away.

Pure dangerous awesomeness!!!!

Now, be forewarned; this is not a risk free project. There are no guarantees that the paint cans or duct tape won't blow apart under the sudden intense pressure. It happened to me once. I didn't wrap enough duct tape around it, and a couple of the sections came apart. 

Flames blow out the touchhole when fired, so be sure and use a long lighter. I watched a vid on YouTube once where some guy tried to light one of these with one of those tiny Bic lighters. He burnt his hand. Bad. Use common sense. A football fired from one of these could probably kill someone if it hit them right.

The combustion chamber will also get hot to touch after repeated firings. 

Did I mention the thing is ridiculously loud?

Some tips for shooting:

Remember that the ratio of fuel to air in the chamber is what determines the success of each shot. Because you can't really measure the amount of lighter fluid you put in each time, it is extremely difficult to get it right. Add to that the fact that the lighter fluid vaporizes differently in different temperatures, and that the oxygen levels in the chamber change after each shot, make getting it right guesswork. You may need to blow out the chamber to get replenish the oxygen supply. I still haven't figured it out. Sometimes I shoot it and the ball only goes twenty feet, and then the next shot goes three hundred. Sometimes I can shoot it twice on one charge, the leftover fuel in the chamber providing enough for the next shot. It's confusing. 

Because the lighter fluid vaporizes differently at different temperatures, you may have to fire it a few times and get the chamber heated up a little before it vaporizes well enough to get a very powerful shot. The hotter it is, the better the naphtha will vaporize.

It is also key to keep in mind that putting more fuel in does not necessarily mean that it will shoot farther. It is the ratio of fuel to oxygen that matters. If there is too much fuel and not enough oxygen to oxidize it all, you get a less vigorous burn. If there is not enough fuel and too much oxygen, you also get a less vigorous burn. It needs to be the correct ratio; and that is difficult get right.