One side of the Fire Triangle is

Heat

Flint and Steel

The flint should be large enough to hold firmly and should have a sharp edge. A clear gray or black flint piece such as is used for gunflints is a good choice. The flint is really any hard mineral around 7 or 8 on the Mohs hardness scale that can keep a sharp edge similar to an arrowhead - agate, jade, bloodstone, chert, flint, jasper, quartz can all work.

The steel needs to be a piece of tempered high-carbon steel since it is the carbon which burns in the spark. Old metal files usually work well and can be found at garage sales cheaply. Steels are normally shaped into a 'C' or 'U' so they are easy to hold and manage. But, I just use a small, broken file from my Dad's old tool box.

You need one other special item for flint and steel fire starting - that is your char cloth. Char cloth is 100% cotton cloth such as old T-shirts or hand towels that has been turned into charcoal. Charcoal is fuel that has been heated to high temperatures without any oxygen. This converts flammable solids into gas, but does not allow it to burn. What is left is black cloth that very readily catchs and holds a spark and begins to burn as a red coal ember. It's easy to make your own char cloth.

Creating Char Cloth

• Cut up an old T-shirt into about 2inch squares.
• Open a can of tuna fish (or cat food) and thoroughly clean, wash, and dry the can. You could use an old steel 35mm film canister or an Altoids tin.
• Poke a small 1/16 inch hole in the center of the lid.
• Start a small fire and let it turn to nice, hot coals. Or, use your gas barbeque grill.
• Fill the can with squares of cloth and firmly place the lid on. The lid needs to fit firmly. If the lid does not fit well, too much oxygen will get to the cloth and it will just burn up.
• Place the can in the hot fire and wait.
• Smoke should come out the hole in the lid as the cloth cooks.
• When the smoke stops, remove the can from the fire and let it cool.
• After the can is cool, open it. If you open it immediately, the cloth may flame up and it is ruined.
• The cloth should be black, but strong. If it is crumbly like ash, it was overcooked. If it is more brown than black, you need to cook it longer.