Let me stress the safety factor here, in no way should any one attempt this or any other metal work with out first having a very good idea of what should be done. The best way is by learning from some one who has experience and can instruct you.
In my forge to start the fire for a new blade I use wood charcoal. {my secret as to what wood or woods}
Charcoal has not generally been used for over a century due to the availability of coal or coke and I have had to learn to produce my own.
This is not referring to charcoal briquettes by the way, although a steak and veggies cooked over a fire in the forge is excellent also.
[*]I start with a hand full of kindling + shavings depending on how large the project placed in the middle of the tweer, once its lit and burning well I rake the charcoal from the outer edges over and around the fire.
Some work requires I pack the heap and others do not.
Once the temp is reached by using the bellows or in my case the air inlet and the fuel has an even color to it I scoot or gently shove the metal under the mound as to disturb the coals as little as possible.
Now its being heated I can tell you that the metal of this blade is about a 3 inch x 6 inch x 1 inch block with a metal tail attached to the short side by a sort of butt-shrinking weld. {more on that later}
Lets say the metal has not taken to the heat as it should so I put on a little more partially heated charcoal from the edges of the forge. I'll add to that out side supply as and if needed during the process.
[*]Using a set of tongs I remove the tail and observe the color by putting it into a box near the forge as its difficult to see the colors in the sunlight.
Metal when heated goes from,
yellow, straw yellow, purple, blue, gray, dull red, sunrise red, cherry red, bright red, light red, almost orange, white, incandescent white, then a liquid appearing incandescent yellow which the surface of the metal has become simimolten, if kept in the fire longer the metal will erupt with tiny sparks that means the metal is burning. Far too hot to use at this stage.
What I'm after is a orangeish white.
{No images possible at this time due to the necessity of using 35 mm film with filters or else you get a white over developed blob of light.}
[*]Placing the block half way on the side of the anvil and striking it with a large hammer an indent is formed. By several more strikes the block is almost cut in half and is then folded over.
At this point if the metal has cooled too far it must be reheated before it can be welded to it self by folding.
[*]I'll add a hand full of chemicals with in the < now and proceed to join the two legs into one block by well placed strokes of the hammer after which the block goes back into the fire to be heated again.
The chemicals do several things include help the weld and to shed impurity's in the iron or steel
A metal worker does not want the steel heated too many times nor does he want it under heated and experience really helps with this matter. Too over heated steel becomes brittle and under heated steel is not as strong.
This folding and welding will be repeated many times. Early Japanese sword masters turned their blades any where from 2 to 200 times. Some were known to be able to shear through a machine gun barrel and let me tell you that is a feat, for the metal of the barrel is very hard and tempered by the heat of the rounds above the heat treatment of the manufacturing process.
In history as well as Myth there are mentioned many swords of renowned character with amazing capability's such as cutting through an anvil then slicing a dropped silk scarf in two. This was done with a blade made in the late 1800's in the UK so its not at all impossible.
In one Myth there were 9 broad swords, some of the 9 match the references made to those that are known from the tales of the round table.
IF you believe in such things...........