Second clay coating attempt

[Mesophilic]

This is my second attempt at clay coating.   The etch is weird and crazy, very deep in spots, not at all like a hamon  but I kind of like the look.  Used vinegar and citric acid.

It W2 4.75" blade, brine quenched.  With apricot wood handles.

Funny thing is, out of all the wood I've worked with, apricot wood is the only wood that smells like its fruit.

[Handforged]

a few schools of thought on the issue of claying.
1. For the most dramatic hamon effect, the lines need to be VERY clearly defined and the clay needs to be of a thick consistency and the same thickness and consistency everywhere that it touches steel. Sharp vertical clean edges and clay about 1/8" thick and very "sticky" to the touch. Dry it for several days or even weeks to make sure that the material used is completely cured and dry. So that it will give the most resistance to heat in the heat treating process. This creates very dark, deep and clean Hamon lines.

2. Thin consistency of material, started heavier at the spine and drawn down to thinner as you get closer to the blade. Clay or substrate is almost watery and can be applied with a brush. This replicates the Japanese style. Where hamons are multilayer and not so clearly defined. The cloud styles of Hamon come to mind.

3. I call this "let 'er rip, tater chip": For me personally I don't use clay in these prescribed methods to create a hamon. I do it to create the effects of a soft spine and hard blade( differential heat treatment). Smeared chimney cement does this job very well. I put it on wet, let it sit in front of the forge to cure a little before going straight in the forge. Let 'er rip.

on a side note, W-2 is said to make a nice clean Hamon. I have not found that to be consistent. 

[Mesophilic]

Thanks for the tips.

I used a recipe...more of guidelines...that I found online. 

Clay, some refractory (satanite), powdered charcoal and wood ashes.  I think my biggest mistake, as you noted, was probably not letting it dry long enough.  I painted the whole blade with a real thin slurry and let that dry, then did the clay coating itself and let that dry for a day.

To keep it even I made a template and marked both sides of the blade so that the coating was the same left and right.

Will try another method on the next attempt.  Also going to hold out for some ferric chloride or PCB etchant.

[Handforged]

ace hardware carries the chimney sealant in a tube you can squirt out with a calk gun for 3.99? It's essentially refractory cement and some sort of water base. Works very well for this. Just treat it like caulk, when you're done shove something into the end of the tube to seal it and it's good for a few dozen or more applications. I like it because it is very consistent. I have never tried mixing my own.

[Bryce]

I used to mix my own, not anymore. Don’t forget to spider in some carefully to the edge. It really reduces the blades resistance to chipping.

[Mr. Woolery]

Also, I’m sure everyone here knows this, but for others who don’t, the alloy matters. Some steels give a much nicer look than others. 1095 has given me lovely results. I just used black furnace cement from a tub. Nothing fancy.

Patrick

[Handforged]

I used to mix my own, not anymore. Don’t forget to spider in some carefully to the edge. It really reduces the blades resistance to chipping.

I'm going to disagree with this for a second with an explanation.

  Carrying the clay down to the cutting edge in any depth will in fact make it more resistant to chipping. Now then, it does that by not allowing the proper transfer of the steel from austenite to martensite rapidly. Which means that the cutting edge in those places will not be as hardened as the rest of the blade ( that is what the claying process is meant to do). This process and transfer to fully hardened is critical to creating a wear resistant cutting edge. To reduce chipping, after the heat treat process a tempering cycle or two will take care of the over hardened chipping issues. The edge your looking for is somewhere in between hard enough to chip and soft enough to warp. Going to fully hardened and then tempering back to a softer steel is where you want to be.

[Bryce]

I used to mix my own, not anymore. Don’t forget to spider in some carefully to the edge. It really reduces the blades resistance to chipping.

I'm going to disagree with this for a second with an explanation.

  Carrying the clay down to the cutting edge in any depth will in fact make it more resistant to chipping. Now then, it does that by not allowing the proper transfer of the steel from austenite to martensite rapidly. Which means that the cutting edge in those places will not be as hardened as the rest of the blade ( that is what the claying process is meant to do). This process and transfer to fully hardened is critical to creating a wear resistant cutting edge. To reduce chipping, after the heat treat process a tempering cycle or two will take care of the over hardened chipping issues. The edge your looking for is somewhere in between hard enough to chip and soft enough to warp. Going to fully hardened and then tempering back to a softer steel is where you want to be.

this is what i meant. Popsicle stick works well
i.e.

[Handforged]

I used to mix my own, not anymore. Don’t forget to spider in some carefully to the edge. It really reduces the blades resistance to chipping.

I'm going to disagree with this for a second with an explanation.

  Carrying the clay down to the cutting edge in any depth will in fact make it more resistant to chipping. Now then, it does that by not allowing the proper transfer of the steel from austenite to martensite rapidly. Which means that the cutting edge in those places will not be as hardened as the rest of the blade ( that is what the claying process is meant to do). This process and transfer to fully hardened is critical to creating a wear resistant cutting edge. To reduce chipping, after the heat treat process a tempering cycle or two will take care of the over hardened chipping issues. The edge your looking for is somewhere in between hard enough to chip and soft enough to warp. Going to fully hardened and then tempering back to a softer steel is where you want to be.

this is what i meant. Popsicle stick works well
i.e.

I figured that was what you were referring to.
 Tsuchioki on katana blades is a whole different animal. Tamahagane has a lower carbon content than most modern high carbon steels that we use.

[Bryce]

I used to mix my own, not anymore. Don’t forget to spider in some carefully to the edge. It really reduces the blades resistance to chipping.

I'm going to disagree with this for a second with an explanation.

  Carrying the clay down to the cutting edge in any depth will in fact make it more resistant to chipping. Now then, it does that by not allowing the proper transfer of the steel from austenite to martensite rapidly. Which means that the cutting edge in those places will not be as hardened as the rest of the blade ( that is what the claying process is meant to do). This process and transfer to fully hardened is critical to creating a wear resistant cutting edge. To reduce chipping, after the heat treat process a tempering cycle or two will take care of the over hardened chipping issues. The edge your looking for is somewhere in between hard enough to chip and soft enough to warp. Going to fully hardened and then tempering back to a softer steel is where you want to be.

this is what i meant. Popsicle stick works well
i.e.

I figured that was what you were referring to.
 Tsuchioki on katana blades is a whole different animal. Tamahagane has a lower carbon content than most modern high carbon steels that we use.

The tamahagane I’ve used reminds me a lot of 1065 or even 5160.