Building a Forge and Making Knives, Part Two.
 |
I finally decided to fire up the forge (see: Building a Forge and Making Knives, Part One), and try hammering a railroad spike into some kind of a knife. The only item I was missing was the air source. Forge blowers on Ebay are fairly expensive, from $150 to $250 average. Considering that I could buy a new gas forge for $300-400, there is no way I am spending that much at this time, with the little I know to make an informed decision. So, I dug out an air-bed manual pump from my storage unit and taped the hose to my forge intake pipe.
I gathered all my tools in the back yard: Forge, charcoal bag, hammer and anvil (from Harbor Freight), gloved, safety glasses, pliers, railroad spike, Zippo, lighter fluid and a bottle of water (to drink!). Now, before you read further, keep in mind that I have never done this before, and have not had any instruction on the matter, or advise from anyone, except the video mentioned in Part One…
I loaded up the forge with charcoal from a bag. First problem.. The chunks in the bag are too big. Fortunately, you can brake them easily with your hands, but it is just more work to do. We had some charcoal from a past bonfire, so I added some to the bowl and sprayed on a bit of lighter fluid. Well, let me tell you that it takes a little more to get the fire going. No problem.. There is enough palm frowns and twigs around to do the job.
Lighting up the forge.
With a little pumping, the charcoal soon caught on fire and crackled nicely. I put the railroad spike in and covered it with bits of charcoal to heat it up on all sides. And I pumped, and pumped, and pumped.. Now I can see how a good blower can make the job so much easier! After a while, the little bit of metal I could see was turning red at last! Time to grab it and hit it hard on the anvil.
And this is why I should have bought a pair of real blacksmith tongues.. Not to mention that the forge gets really hot, and I burned my hands a few times under the gloves. My air source must not have been sufficient, because I couldn’t get the heat quite high enough, and only had a few hammer blows per heat to work with. I should have started by lengthening the spike instead of flattening the blade first. Now it will be harder for me to do it later. I bent the spike like for a drop-point blade to make up for the curving that will happen when I hammer the edge in. Hammer control is pretty difficult. Not only do you have to hit the blade where you want, but you also must keep the hammer face parallel to it at the same time. Right now I am just rough-shaping the knife, but later, any mistake will leave gouges on the metal that will be hard to correct. I also had to be careful to work on both sides equally to keep the blade aligned with the handle. As the edge became thinner, it had a tendency to fold on itself, so every three heats, I would hammer it gently back in. After four hours of efforts, this is what I had:
Top view after four hours of work.
Pretty slow work.. I will try to find some kind of electric blower for part three. Advise would be welcome, please use the comments. At least I am making progress. I want to get the blade as close as possible to it’s final shape before using any tools on it, most likely a file. If I really get into this hobby, I might get a gas forge, but I want to finish this one with th charcoal forge, just to be able to see what can be done without much technology and experience. If I get a usable knife, if not good looking, I will be pretty happy.
June 10th, 2009 at 17:51
Sir, I highly recommend using a blow dryer for your forge air supply. If you can find a connector that will enlarge the pipe enough to allow the blow dryer to fit snugly to the pipe, that is wonderful. If you cannot, I find that it does not matter much. Also, for your forgings to be productive, I recommend using lump charcoal (you should be able to find it at some butcher shops, hardware stores, grocery or general stores, but let your fingers do the walking… again, lump charcoal works, briquettes and wood will generally be a waste of time to use). There is one more thing you can do to increase the efficiency of your forge, and that is to set up refractory bricks (gotten from a refractory supply or an unusually well supplied hardware store) on the surface of the forge itself to choke the charcoal right on top of the air holes and reflect the heat on either side – then stick your work straight in the heart of said coals and it will heat up quickly. As for tongs, you dont need them for this kind of work, and you need to make a new pair for every thickness of steel you work with (blacksmiths can have more than 100 pairs they made over the years). You can still make a pair, plans for them can be found on anvilfire.com. I prefer the easy route, and use self adjusting vice grips. I simply dip the jaws in water between heats, and wear heavy leather gloves. Good luck.
June 10th, 2009 at 17:54
I wish to clarify my term “choke” in regards to the placement of the refractory bricks. Simply place them so as to leave an opening just wide enough to heat the steel and place your charcoal between them so as to concentrate the heat of the fire on your piece of steel.
June 10th, 2009 at 18:59
Very informative, thank you very much!
June 19th, 2009 at 16:59
Well, I ordered a gas forge, which should be here on Monday. I like the charcoal forge, but I just don’t have the time.. So, stay tuned for part three where I will finish forging the knife.