Just finished the first knife I made since I started blacksmithing (about a year ago). It's made from one single railroad spike. I tried to clay temper it, but I don't know if it worked very well. After one heating and oil quenching with clay, I heated it 2 more times and quenched it in oil, then once in water, then heated it once more and let it cool. The dark marks on the blade are leftovers from where I got carried away during forging. Total length is 11 inches. 7 inches of blade and 4 inches of handle and pommel.

But I learned a few things: Smaller lumps of coal (golf-ball sized or less) work better than large lumps. At some point, the fire got hot enough the coal and slag and everything else started to melt. It got sticky. That was when I got my best results. So it was a good learning experience.

I apologize for the quality of the photo. The downside to fluorescent lights is that the lighting sucks.



Any comments or suggestions would be welcome.

Yes, it is a very nice work, congratulations!
I can't give you any very valuable suggestion, because I've got no much more experience than you (blacksmithing since a year and a half).
But one thing I've learned, is to focus my production on some particular stuff; in my case, these are knives and arrowheads.
This because those are small items but forging them is very useful; you learn a lot of thing e.g. how to make a straight blade and how to make a cylinder.

Just one question, what kind of coal do you use?
Because I don't do so many quenches, just one fits me, once I've forged the knife for a certain time, at the right temperature, using artisanal coal.
Greetings,
Mauro.

Ok, let me tell you my experiences.
I usually quench only once, too, and results have been different.
I use a coal made out of oak and chestnut, in my Iron Age forge (a pit in which leather is immitted by a leather bellows), and forge only raw iron, not steel. Despite the simplicity of the design, the forge is capable of reaching high temperatures: I melted the iron twice.
After all this time, I understood that a successful forging somehow depends on the ingot's dimensions, on the time it's been heated and hammered, and in the color it has when it's quenched.

Basically, a 3 millimeters thick ingot, requires about 4 hours of forging to get enough carbon molecules. Best quench is at cherry red, or bright orange. More will cause the iron to be too brittle.

Pay particular attention when you have to weld, for you need to work at very high temp (coal white, just before melting temp), and after the welding you'll have to quench; then heat again to mantain the weld but remove the brittleness.

This weekend I'm going to study temperatures and test different queches (water, frozen water, water with oil surface, oil) for my thesis, by making 4 blades out of iron ingots; I'll then try to bend them and see the differences. Stay tuned 
Greetings,
Mauro.

Better pictures I took this morning:

That looks pretty neat for homemade, i bet it works good.

Let me say... should you ever be interested in metal melting (bronze or brass, for making knives furnitures and so on), you should close your pit, that you make with bricks.
Then, put a pot full of water on the top flat brick.
As the water boil, you've reached the right melting temperature for any copper alloy 
Greetings,
Mauro.

I'm presently trying to learn to blacksmith.  I don't really have a good forge, though.  It's just a deep, angled pit, with a steel panel on top that has two vents for air circulation when I'm fanning the fire.

African blacksmithing is exactly what I'm studying with my thesis 
My Iron Age forge replica is build the African way, not having any archaeological finding.
Greetings,
Mauro.