If you’re like me you have scoured the internet for instructional videos, blogs and images.
When it came to creating the “elusive” hamon, that’s about all I was good at, searching the web. I thought I was doing everything right. I had the right tools and supplies at my disposal but could not get that ghostly wave to appear.
The problem I was having was not with the tools but the execution. I had to take a step back and think, how was a hamon really formed on a metallurgical level. What is happening during the quench that makes this happen?
Starting from scratch.
I am no scientist. Everything I have learned about knife making has been sourced via internet, but I think I have it figured out. When the spine of the knife is insulated with clay, heated to critical temperature and then quenched in oil, the non insulated area is hardened and the insulated area is soft. You probably already knew that. My problem was the layer of clay on my knives was too thin, thus not insulating long enough to produce a hamon.
When I make kitchen knives I typically have a spine thickness of 1/8”. I figure why not lay it on thicker, at least the thickness of the spine. This held the heat better that the thin layers of clay like before.
Quench as usual
I quenched my insulated blade like I normally do. This was a 1095 steel that was heated to critical and rotated in the forge to keep the heat even. Quench, check for warp (most of the time there’s a warp with thin stuff) and straighten.
Grind and sand
Grind your bevels and get ready for the tedious job of hand sanding. Mirror polish, or close to it is ideal to bring out the details in the hamon. I brought my blade to 2000 grit, buffed with green rouge and cleaned thoroughly with alcohol. You should be able to see the hamon clearly by now.
Etch and polish....the fun part
I have found that distilled white vinegar works the best for me so far. Warm the blade and vinegar just a bit, not boiling, and let it sit for about an hour. This is all an experiment so play around with different times or temperature if you like. I was just winging it. Pull the blade out and clean off the oxides that have built up as they will hinder further etching. Drop the blade back in for another hour and repeat until you have a look you desire. When it comes to polishing, I have read some maker use 1500 grit powder for this step but all I had was meguiars diamond cut buffing compound. It worked surprisingly well. If it’s good for automotive clear coat it must be good for metal.
Experiment and see what happens
This whole process was just an experiment for me. I have been unsuccessful before but that is part of the fun. If it were easy, everyone would be doing it. Net time I’ll try to put more of a pattern in the clay to give it a little more movement. Have fun with this project like I did. It was super satisfying and I will definitely do it again.