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How to Start a Fire?: Newsletter Challenge (11/22/05)

Posted November 22, 2005 6:00 AM

The question as it appears in the 11/22 edition of Specs & Techs from GlobalSpec:

You're driving in the middle of nowhere on a bitterly cold but bright sunny day, and your car simply dies. (Turns out your alternator had failed miles back and now you've run the battery dead.) Your cell phone is of no use, you have no idea how long you'll have to wait until the next car comes along, and the family is grumbling strongly about how cold they are. You have no matches and no battery but you scan around and see plenty of wood and kindling near the frozen pond nearby. How to start a fire? You've got a toolbox in the trunk (the usual stuff — wrenches, screw drivers, a small hand saw, and other bits and pieces) and then it hits you. What do you do?

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The Engineer
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#1

A couple of guesses

11/22/2005 9:58 AM

The engine should still be hot, use it to get the fire started. I'm not sure if this would work, but it's the first thing I'd try. Remove the battery from the car and bury it in the snow. If you cool the battery for 5 minutes you might be able to generate some sparks. Use the sparks and some gasoline (from the tank)to start the fire. Take some gasoline and bang to metal parts together to generate sparks to start a fire. Carve some ice from the pond into an ice lens, then use the sun and the lens to start the fire. Your family will really appreciate the fire since they will be close to hypothermia when you finally get this to work.

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Power-User

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#13
In reply to #1

Re:A couple of guesses

11/23/2005 9:48 AM

It's too bad that the car has electric windows and you had them down when the car quit running, otherwise on a bright sunny day, just staying in the car would keep you warm. Use your credit cards to scrape the inevitable frost buildup off the windows to help with the solar transmission into the car. If you had thought quickly enough, the catalytic converter would have been hot enough to start kindling on fire, although getting to it would be difficult and possible dangerous if you use the tire jack. Adding some water from the pond to the battery (if the cells have removable covers) may help you generate a spark to ignite some kindling. Usually when batteries run down, the upper part of the plates become exposed and covering them with water gives you a little more umph. Warming the battery up would help. It's a chemical process that works better when it is warm. Take the battery out and put it in the car where the sun will shine on it (assuming you have the right size wrenches). Making an ice lens would be time consuming and assumes the ice in the pond froze clear. Odds are you would not have the right wrenches and torque drivers to remove the headlight assemblies to try to use them as a lens to focus sunlight. Most of the plastic headlight and tail light assemblies on cars are sonically welded together and would have to be crushed to get at the reflectors, an expensive proposition.

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Guru
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#2

Steel

11/22/2005 11:53 AM

Send the family wood gathering, that'll warm them up - and when they get back, get them to bundle together and share body warmth.

Presumably the spanners (sorry wrenches) are made of carbon steel...so get your kindling together, soak with a little petrol (if you're stupid enough to drive a gasoline car rather than a sensible diesel then there will be plenty, else use the WD40 you keep in the tool kit) and draw the saw quickly across the waist of the spanner.

You should get loads of sparks and after a few tries you should light the kindling. Add rest of wood without extinguishing kindling.

Personally, I'd pull my firelighting steel out of my handbag and use that, but hey....!

Alternatively you could dismantle one of the headlights and use the lens to start a fire from sunlight...but given it's winter, I think you'll end up in Roger's situation of a family with hyperthermia - even after bundling!

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#3

Try this

11/22/2005 1:35 PM

This is what I would try first. If the car has a carb, remove the air filter so that you have a clear view down the top, take a small piece of kindling and stick it down the bore of the carb, work the linkage and you will see fuel spray on the kindling from the accelerator pump, now you have a fuel soaked piec of kindling. If the car is fuel injected, the fuel rail usually has a bleed point, sometimes it looks like a valve stem on a tire, simply use the kindling to press the inner point in the stem to soak it with fuel. Now all you need is an ignition source. Find two short pieces of wire, and strip both ends of each, disassemble the cell phone and use the battery and two pieces of wire to short across the terminals for a spark. Now you have a burning piece of kindling, use other kindling and the nearby pile of firewood to keep you family from freezing to death. This should work for all of you non-smokers, I would simply flick my bic and light the kindling.

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The Feature Creep

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#4

The gun on the mantle

11/22/2005 3:59 PM

consider there are 2 things that are out of place in the description, the pond and the saw, I will have to assume the answer is cutting a hole in the ice with the saw to put the battery into and then using it to make a spark for some gasoline soaked twigs.
Just remember that gun on the mantle in act one must go off in act 3.

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The Engineer
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#5
In reply to #4

Re:The gun on the mantle

11/22/2005 4:34 PM

Yes, I think my "ice lens" anwer was the "gun on the mantle" answer. Notice that "Bright Sunny Day", "Saw", and "Pond" are mentioned and notice also that the question goes out of the way to point out the battery is dead, as opposed to the more likely "running out of gas".

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Anonymous Poster
#6

Quest for Fire

11/22/2005 4:42 PM

It would seem that the tools in the toolbox would be a useful resource for generating a spark. However, there actually should be enough battery current left to act as a source for sparks, since the modern electronically fuel injected car will most likely stop running long before the battery is fully exhausted. You can also use a turn signal lamp as an igniter, but you will get only one shot of it because you need to break the glass. It would be helpful if you can somehow retrieve some gasoline by loosing a fuel line or hose and soaking some kindling.

A traditional method for retrieving gas is by siphoning. Siphoning gas is an age long trick for beating the ill effects of winter cold. The process goes something like this. First locate a hose of suitable length and insert one end into the gas tank of the car by threading it into the filling spout. In order to create a siphon the other end of the hose must first be below the level of gas in the tank, so lie down on the side of the road, exhale strongly, and insert the free end of the hose in your mouth. Now draw hard on the hose by sucking. Invariably, you will feel some resistance, but all at once a mouthful of gas will come gushing your way. At the moment you start to swallow the gas you will spontaneously rip the hose free from your mouth with a stream of gasoline in tow. If you are really lucky, the loose gas will spill between your legs. Gasoline has a number of useful properties, particularly when it makes contact with the inner workings of your stomach and sensitive areas of the epidermis. The net effect will easily take your cares away from the bitter cold as you reel from the gastric disturbances and the endless burning of your sensitive skin.

If you can not or do not want to use gasoline, in a pinch you can use the carbon steel tools and a rock to generate sparks, but to be a real man you must rub two sticks together. More about this macho technique is described next.

According to Wallaby's "Seven Essential Things You Should Know about How to survive in the Woods", the best technique for starting a fire with two sticks is to get someone else to do it. If that does not work, and it seldom does, you must resolve yourself to the fact that you have become the victim of the "Downward Leaping Monkey" syndrome. A downward leaping monkey is simply a problem that germinates on the back of someone of superior authority and is subsequently delegated to the first available underling. In turn, that underling will soon shed their newly acquired "monkey" onto the next underling that falls under their authority. The process continues until there are no further underlings in the social chain. For some great cosmic reason that escapes the understanding of many philosophers of our time, that last person in the long chain always turns out to be you. We could delve further into the nuances and social underpinnings that fuel this idiopathic process, but that is beyond the scope of this writing at this time and is left to the reader for further research and independent study. To that point, we must return to our personal "Quest for Fire". Our story now continues somewhat where we left off.

The first thing you must do to make fire from two sticks is make a bow. Locate some rugged string or cord (Wal-mart stocks this in their sports department) and find a suitable stick that will bend with enough tension to string a bow. Next, find another stick that is about one half inch in diameter and a dry log. Create a pocket in the log with a rock or screwdriver. Place the stick into the bow by wrapping the bow string around the stick. A second piece of wood with a pocket captures the top of the stick and the bottom goes into the pocket of the log. By drawing the bow back and forth the stick will rotate and create friction at the ends. You must do this vigorously and for an extended period of time to create enough heat to light a small fire. However, you will get plenty warm with all of the activity, so it isn't really important if you actually can start a fire (and you won't). At least that is how the Indians tell us how to do it. No one is sure if they really did this or they are simply providing us with what is know as "Mexican Directions".

An Indian proverb states: in the end you can build a fire and keep a man warm for the night. Subsequently, you set a man on fire and keep him warm for life!

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Guru
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#9
In reply to #6

Re:Quest for Fire

11/23/2005 6:41 AM

A friend of mine has a fire bow and has promised to teach me how to use it...and so I will probably make my own sometime. When this happens, I might remember to let the CR4 crowd know how it went (then again you might not be interested!)

[Is my alternative nickname of Firestarter becoming apparant?]

On the fire bow subject, it is important that the rotating stick is of a hard wood and that that socketed lower piece is of a softer wood (I've been told). And you need to feed tinder into the socket as it warms.

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#7

Challenge Question

11/22/2005 5:16 PM

WWMD (What Would McGuyver Do?)

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Anonymous Poster
#8
In reply to #7

Re:Challenge Question

11/23/2005 5:15 AM

luckily im a smoker and although the answer states i have no matches, im fortunate enough to have a lighter in my back pocket. the rest is easy

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Guru
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#10
In reply to #7

Re:Challenge Question

11/23/2005 6:51 AM

Who's McGuyver?

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Power-User

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#11
In reply to #10

Re:Challenge Question

11/23/2005 9:02 AM

Sorry Rosie, I spelled it wrong, it's MacGyver. Angus MacGyver is an American folk hero for engineering geeks and wanna-bes. He was a character from an 80's TV show here in the US that would get out of complex situations by creating tools or explosives from items just laying around. They have even named multi-function hand tools after him. http://store.bicyclerevolution.com/mcguyvertool.ht ml

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Associate

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#16
In reply to #11

Re:Challenge Question

11/24/2005 3:15 AM

You know in Malaysia, I love to see Mac Gyver movies and Oh.. Boy I never miss his movie. I always learn new trick from him. I wonder what happen to him??...

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Commentator

Join Date: May 2005
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#18
In reply to #16

Re:Challenge Question

11/25/2005 6:17 AM

He got beaten up by the A-Team, maybe?

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Participant

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#19
In reply to #18

Re:Challenge Question

11/28/2005 9:33 AM

Everyone knows Mac Gyver joined the military, got old and cynical, then went through the Stargate.

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Anonymous Poster
#12

is fire really the solution?

11/23/2005 9:04 AM

In this situation, i think the quickest way to warm up the family, would be for them to get round the back of the car and start pushing... maybe you'll find a phone/garage/help, maybe not, either way stay in the car to steer, wind up the windows and hopefully you wont be able to hear them whinging.

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Anonymous Poster
#14

possible solution

11/23/2005 10:58 AM

I would think that since you have basic hand tools, ice and kindling you would cut a block of ice from the pond and shape it into a lens. Once you had the basic shape down you could use your hands to melt it smooth. Then take the lens and the bright sun light and concentrate the light like a magnefying glass on the kindling until it smolders and lights.

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Anonymous Poster
#15
In reply to #14

Re:possible solution

11/23/2005 2:11 PM

I am struggling with the idea of making a lens from ice. Typically, ice cubes contain some solutes and lots of air bubbles trapped in the freezing process that make for an opaque object.

On the flip side, I seem to remember that water, when it solidifies slowly, will drive out particulates. That is more theoretical than practice, since a lot will depend on the rate at which water freezes. Tap water tends to have a lot of trapped air. When placed in the freezer it freezes rapidly and ice cubes look opaque. If the freeze process is slow enough, the air will percolate out first and the cube will look clear (or clearer). I would expect the pond water to freeze slowly because it is a huge heat sink and typical seasonal temperatures change slower than you would get when making ice cubes in the freezer.

What really happens to pond or lake water when it freezes is not clear to me (no pun intended), but I wonder if it would be optically clear enough to function as an efficient lens.

The next hurdle is actually shaping ice into a convex lens accurate enough to focus enough sunlight to ignite wood (or even paper).

It would be interesting to see if anyone can empirically test this. Temperatures are getting much colder up here and you could run an experiment to see if it is possible. Here is what I propose:

1) Buy a cheap lens from the store and some molding clay. This will save time shaping a lens.
2) Make a mold of each side of the lens with a fill hole at one edge. This is a two-part mold.
3) Purchase some distilled water, open it, and let it stand for a few hours to let any trapped air escape.
4) Pour the water into the two-part mold and place into the freezer overnight.
5) Remove the ice lens from the mold. It would be nice to do this outside where it is cold.
6) You may need to remelt the surface of the lens to create a smooth surface.
7) Purchase some ants from your local pet store and go to town!

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Participant

Join Date: Nov 2005
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#17

Re:Fire

11/24/2005 8:59 AM

My toolbox always has pieces of steel wool because I do plumbing work. I would use the screw drivers to complete a cicuit between the positive and negative poles of the battery. There should be just enough juice to get the steel wool to burn and start some small pieces of wood that have been cut up with the saw.

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Participant

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#20

starting a fire

11/28/2005 9:36 AM

If I've learned nothing else from watching modern action movies, it's that today's cars will go up in a ball of flame with the slightest of impacts. Get the family well clear of the area, preferably behind a huge boulder or down into a ravine. Now take the tool box and heave it at the car, remembering to run like mad since the blast radius will be immense. Not only will the resulting fireball keep everyone nice and toasty, the explosion should also bring the local rescue league running.

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#21

Re: How to Start a Fire?: Newsletter Challenge (11/22/05)

09/17/2006 7:56 PM

Make a bow from some of the wood(shaped, if necessary, by what ever suitable tools on hand)and someone's shoestring, and since there is ample wood and kindling , all should be well.

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