Jes, where to start Mark.
What was the class like?
The first thing for me was Murray Carter himself. I've taken a number of classes on different topics from people one could say are masters in their field, and several I've walked away from because the master as it where couldn't help but show what a master he or she was in a way that was demeaning. Murray is very cool about the skill he has. He doesn't flaunt it or put it in your face in any way. That's not to say it wasn't evident, but it was used only in the interest if making an awesome knife or teaching. That worked for me. I am very allergic to blow hards regardless of how talented they might be.
Murray's main focus in knife making is on the metallurgy. Making the metal as good as possible for the blades intended use. Yea, blade shape, thickness, grind, steel selection, etc, are all very important, but if the steel is not forged correctly, at best it won't be improved by the time it gets to blade stage, or at worst, it will be degraded.
Too hot at any point and the grain in the metal grows to a point where the blade will be brittle and not sharpen well to boot. Murray had a great way of explaining grain in terms of a bowl of marbles. Obviously simplistic, but....The bigger the marbles, the less contact area between them and the weaker the metal will be. The smaller the marbles, the more contact area and hence more strength. So by controlling the heat process and hammering the steel, you can make the marbles smaller thereby improving the steel over its initial state.
And this where experience comes in. Its not just a matter of heating and hammering. There is a "right" temp for the first heat, a temp that is reduced by a certain amount in each additional heat as you forge the steel into an appropriate shape. This is before the heat treat phase which has its own subtilities. What are these temps? Murray can give you an estimate, but he arrives at the precise temp by testing blades after the final heat treat process and then makes mental notes to modify the earlier steps on the next batch he makes. Through this process, the exact temp, judged by color, is refined to produce the optimal end result. So while I have the numbers, I am doing my best to remember the colors until I get my forge up and running and can turn what is presently stored in my rather aging brain into something a bit more practical.
So after the initial forging and annealing into rice straw ashes, again to a very specific color, we trimmed our forged billets to the shape of patterns. The first two knives where cut to Carter patters, the last knife had to be an original, i.e. a patten the student comes up with.
Once cut out and ruff shaped, we cold forged the blades. This is a process of running the blade under the power hammer cold. Hit it to hard, and the metal cracks. Hit it to soft and nothing happens. The idea at this phase is to introduce stress into the metal. Yea, who would have guessed, but it makes a difference to the final blade.
Then it was onto a tree stump and brass hammer to straighten the blades.
Holy sh$%, who would have guessed how friggen hard it is to get a knife perfectly straight. Again, there are lots of techniques, ways of holding the blade to different sources of light to see the imperfections, but getting them all out took some serious learning. Was great to see Murray and Kenny straighten blades to a point where there where no visible problems in anything from a few seconds to less than a minute. I remember the second knife I made, the kitchen knife, I must have spent 45 minutes straightening that and still couldn't get the placement of the tang just right. As soon as I moved the tang, it put a bend somewhere else. As soon as I fixed that, the tang was out again. I got Murray to take a look. He looked from about 10 angles, put it on the stump, whacked it once, just once, and like magic, the friggen thing was perfect. Anyways. Very cool.
Once the blades where straight, we coated them with clay which stops the bare metal from self insulating, and prepped for the heat treat process which was virtually a religious experience. Murray showed us a technique where the shop is darkened except for a single 40 watt light bulb. The idea here is to see the color of the heated blade better. The reason for the dim light bulb as opposed to just doing it by the light of night is to control the luminescence so you can see the color of the blades heat better. Again, like the forging process, Murray heats the blades to a slightly different color then the blades done earlier based on the results of tests run on the earlier blades and then with a Japanese utterance, he quenches them in preheated water. I'll point out here that this is in no way rote for Murray which was a totally cool thing to experience. After doing it for 27 years, each blade he does is special to him. You could see it in the way he treated each blade and that was really neat for me. To see someone that after 27 years of doing more or less the same thing, to still be totally engaged in it, to still be refining the process and loving it. Totally awesome.
Next up, myself and my two fellow students got to do ours. The first one I did blew my mind. With Murray standing right behind watching the color and position of the blade in the fire, quietly making suggestions, you get this really weird connection to the steel and the process. The process is so subtle. The movements in the fire. The color changes. The way the metals feel changes as it heats as it moves against the charcoal, and when it is just right, plunging it into the water. You could virtually feel the metal harden. Seriously. Not many things I've experienced that where that intense in such a cool way. Next the knives go back into the fire to temper, and air cool.
After that, the lights come on and its back to reality after this surreal trip.
The blades at this point are cleaned with a brass brush and then the secondary edge ground on them starting with the big water wheel. One of the thousands of questions I asked was why not forge the secondary edge into the blade. The answer was that the heat treat process acts differently on a blade that thins instead of being of a more uniform thickness making the hardness through the blade un uniform. This is fine but as you sharpen the knife and it shrinks over the years, its performance will diminish as opposed to remaining constant. The distal taper is forged btw. Back the grinding. Its done on the large water wheel, flat belt sanders ( flat grind ) and done bare hand with lots of water. Again, a lot of focus on temperature control, hence the bare hands and water. We ground down and into the carbon steel, almost but not quite making the final edge.
That pretty much concluded the metal work part of the process.
Next up the handle wood was chosen from a huge pile, cut on a band saw, sanded, glued and pinned inlace, shaped and final hand sanded, then buffed.
After that, the secondary edge got its final finish on the flat grinder and then onto the sharpening stones for the primary edge, King 1000 / 6K in this case. I did not ask him why he did not use what many would consider better stones. It just felt like too retarded a question to ask given he gets hair whittling results with the Kings in less than 45 seconds.
Anyways..... Was a great class and left me with a serious hankering for one of these......