Starting Fire with Flint and Steel – How It Works and Why It’s Not Really a Good Survival Plan
For hundreds of years prior to the invention of the safety match, flint and steel was the most commonly used method of starting a fire. The mechanics of flint and steel are pretty straight forward. You strike a flint rock with a piece of steel which produces sparks. The sparks fall into a combustible material where they take hold. The combustible material is transferred to a bundle of finely shredded tinder, and you blow on the combustible material to expand the spark and make it hotter. When the heat reaches a critical temperature the tinder bundle ignites.
Starting a fire with flint and steel is a skill that is still widely practiced by re-enactors of the French and Indian War, the Revolutionary War, and the American fur trade. When I was a kid ever Boy Scout in my troop was expected to start a fire with flint and steel and bring a pot of water to a boil in less than five minutes. Sadly, this is a skill that is no longer taught in scouting.
Now for the movie myths about starting a fire with flint and steel. In a scene from a popular movie about a young boy stranded alone in the Alaskan wilderness, the boy throws his new stainless steel axe and it hits a rock creating a shower of sparks. He gets a great idea. He picks up the rock, gathers a bundle of dry grass, and then bangs the rock and axe together making the sparks fall into the grass. The grass bursts into flame, and the boy has created fire. Nice movie scene, but it will never happen. Here’s why: Most people thing that when flint and steel produce sparks, it’s the flint that is sparking. Actually it is little fragments of the steel that are burning. A hard, sharp edged rock like flint will shave tiny pieces off of the steel, and the heat created by the friction of flint dragging across steel is sufficient to make the steel burn. Now, for the steel to burn it must have a very high carbon content, and stainless steel does not have a high carbon content. So, it won’t produce sparks. If you don’t believe me take any modern stainless steel knife and bang away. You won’t get any sparks.
The second reason why the above scenario wouldn’t work has to do with the heat of the sparks produced by striking flint to steel. The sparks produced by striking flint to steel are not hot enough to directly ignite a tinder bundle like dried grass or shredded cedar bark. To get the bundle to ignite you first have to catch the spark in an intermediary material that will catch the spark and ignite into a weak glowing burn. This material can then be transferred to the tinder bundle where a little blowing will cause the glowing material to burn hotter and will keep it in contact with the tinder for a longer period, allowing the heat to build up to the point of combustion.
The most commonly used intermediary material for starting a flint and steel fire is char-cloth. Char-cloth is cotton or linen cloth that has been burned inside of a nearly air-tight container so that it turns into a fragile, blackened char that is easily ignited.
Other things that I have personally used as char include charred fungus from a tree, and charred punk wood, which is a soft rotted wood. I have also read about a particular type of fungus that will catch a spark without charring if it is thoroughly dried. I believe it, but I’ve never seen it or tried it myself.
In fairness to the legend of striking sparks directly into natural tinder and starting a blaze, I have heard that it can be done. But I’ve never done it, and of the hundreds of people that I personally know that can start a fire with flint and steel, none of them can do it. So, I would say the chances of the average Joe making this work are not good.
There are a couple of man-made substances that you can ignite will a flint rock and steel. These are 0000 steel wool, and gun powder. I find it unlikely that you will come across any steel wool in the wilderness, but if you are hunting you will have some ammo. If you open a cartridge and pour out the powder, you will have something that you can light with flint rock and steel.
So, I don’t really consider fire by flint and steel to be a great option for survival fire starting. To start a flint and steel fire under survival circumstances you would need to have or find something made of high carbon steel, you would have to be in an area where flint rocks can be found (not as common as you would think), and you would have to be able to identify and dry some of the mystery fungus that doesn’t need to be charred, or stumble across an old campfire that contains some charred punk wood. Sounds pretty iffy to me. Of course you could carry a flint and steel kit with you everywhere you go, but wouldn’t a disposable lighter be easier?
With all that said, let’s learn how to start a fire with flint and steel anyway. You never know, and besides it’s kind of fun. In the next post we’ll start getting our equipment together by finding a flint rock and selecting a fire steel.
Sensible Survival 
Your explanation of why a flint and steel spark ignites is a bit off. It is not the friction that generates heat. It is the steel oxidizing that generates the heat. Hand warmers work on the same principle. They are basically fine steel shards that begin to rust when activated and generate heat.
Didn’t know that. Thanks. Hank
The ancient Egyptians, Vikings, Romans, Inuit, Fur Traders, etc all relied upon F&S. The reason most people believe F&S is not a worthwhile form of fire ignition has vastly more to do with their lack of knowledge and skill than the viability of the method itself. Further, it is very difficult to find a more “green” and sustainable form of ignition than F&S. Most modern methods of ignition are neither faster, easier nor more reliable than F&S in the hands of the skilled practitioner.
By way of comparison matches, lighters and ferrocerium rods have only been around for barely more than 100 years. F&S ignores the wind, which is something we’ve all wished matches and lighters could do! Further, it is pretty much impossible to manufacture your own matches, lighters or ferros in a primitive or SHTF type situation. Not so with F&S, as I will make clear below.
There are hundreds of types of rocks that work and they are plentiful across the globe. The common denominator is quartz, though any rock that is 58 HRC or higher and has a sharp edge works. Dozens of types of granite, sandstone, onyx, agate, chert, jasper, obsidian, quartz, flint, etc all work.
There are dozens of natural tinders that will catch the sparks from F&S in their UNCHARRED state and hundreds more that will when charred. Most fungi, plant fluffs, plant piths, softwood trees, punkwood, etc work charred, uncharred or both. Natural tinders can be charred without the use of a tin by several methods. Indeed, without any container at all. Speaking of tins, most tins do not need any holes punched in them. The less chance of any oxygen entering the tin the better, as long as enough gases escape that the lid stays on. For those tins that do need a hole, drilling a 1/16″ hole through both the side of the lid and the wall of the tin offers many advantages. Align the holes to make char then put them out of alignment to protect the char. This works with any symmetrically shaped tin such as rectangular, square, round, oblong, etc.
There are dozens of steel implements that will throw sparks with flint (the rock) such as saw blades, shovels, knives, axes, files, fish hooks, etc though not every item of each type will work. Most hacksaw blades are better strikers than most purposely made strikers, knives, files, etc though some hacksaw blades will not work at all. Some iron pyrites, most notably marcasite, will throw good enough sparks with flint (the rock) to create an ember. While most stainless steels will throw some sparks with flint (the rock), the sparks are so few and weak as to be worthless for creating embers. Steels from 1055-1095, O1, O2, A2, W1, W2, L6, etc will throw sparks with flint (the rock) very well if they are hardened to 57-63 HRC.
Once you have suitable rock, steel and tinder, the next most important aspect is speed. The faster the rock and steel are moving the better. While an expert can achieve a coal in a single strike by only flexing his wrist, it is better for most people to give yourself plenty of elbow room, start high and swing through as quickly as you can.
Here is an excellent article and video on F&S. I have been doing the same things that Paul is doing in the jungles of Malaysia with the local materials here in the Upper MidWest for many years. http://www.junglecraft.com.my/index.php/advanced-flint-and-steel/
I offer up these brief few words on the subject in the sincere hope that they will help people have a better understanding of F&S and its viability as an ignition method in all locations and all situations.
Happy Trails y’all!!
John,
A lot of good information here, and I appreciate you commenting, but let me ask you a question. Primitive man used stone tools for something like 300,000 years but don’t you think he would have traded all the stone tools he ever owned for a Leatherman multi-tool? Look no further than our own Native-Americans for the answer. They switched from stone to metal as fast as they could trade for it. Just because something has been in use for 3000 years doesn’t make it the best way to to do it. It’s a perfectly good way to do it, but it’s certainly not the best way, or we’d all still be using flint and steel You obviously have a very special interest in this skill, and I applaude your expertise but my advise to the average guy (or gal) remains the same. Learn all you can about different ways to start fires, but carry a Bic or a fero rod. They don’t take up much room, and you don’t have to be an expert to use them. If you’re worried about SHTF long-term survival, buy 50 fero rods. 25 of them will last you a life-time and the other 25 will make excellent trade items.
Thanks for reading,
Hank
I think your thinking is a bit flawed.
1) Flint and steel very easy to use if you have something like char cloth or king Alfred’s cakes (fungus)- managed to easily ignite both of those today having never struck a true flint and steel before. Ok, so in a survival situation you need the fungus or the cloth. But with a shop bought device- with magnesium content there were sufficient hot sparks to ignite dry grass without another medium to hold the ember. In any case- if you went out unequipped I would suggest your chances of sourcing flint and steel are better than your chances of sourcing a box of matches. And something else to consider is its just the steel really that you need- the flint could be substituted for another sharp rock such as quartz (which is available locally for me)
2) Its probably safer to keep a flint and steel in your bag than a lighter (nb don’t lighters use flint and steel? I remember taking the inner workings out of a dud lighter in scouts and using it to make a fire without fuel. So you could have one with you- and it will light 1000s of fires for you- unlike said lighter which will run out of fuel, or matches which also will run out. Scout motto (at least in the UK) is be prepared.
You might find this interesting as it explains how the flint and steel works.
http://survivaltopics.com/flint-and-steel-what-causes-the-sparks/
Jenny,
All your points are well taken. As a former US Scout leader (our motto is also “Be Prepared”) I always keep a small Scout’s fero-rod striker attached to my key ring. Always with me and more reliable and convenient than than flint and steel. Also taught my students to start fire with an empty lighter, flint and steel, fire-bow-drill, magnifying glass, batteries and steel wool. Keep all options open. Personally, I would rather be prepared with a fero-rod than have to depend on locating the necessary materials for flint and steel fire in the wild.
Hank
I have taken to lighting bonfires using F&S on lint that my wife gets from the clothes dryer. Not that there’s much lint available in nature, but it is very light to carry.