Best and First Clay-Created Hamon I've Ever Made....

[TikTock]

Heres a sneak peak at my latest....

15" OAL
10" Cutting edge
1095, Diferentially Clay Hardened

This was my biggest blade so far, and my first real foray into clay. After a lot of research, I was able to produce something that surpassed my initial expectations. Impossible to photograph....multiple layers in every curve...

Three pics:
1. Pre HT
2. Clay applied and hardened
3. Post quench
4. Final finish before bolsters and handles go on

[Andrew Garrett]

That turned out nice Dave!

[TikTock]

Words cannot express how dificult it was to etch this thing. I wanted to see that varyng lines I was lucky enough to end up with, but they are so subtle it became a war of etching, then removing carbides, then losing the secondary pattern even wiping clean wth a paper towel. In the end, it probably took 12 etches, each about 10-20 seconds, with 0000 steel wool and paper towel poishing in between. It is a nice satin with lots of action now, and the hamon is vey clearly visible on the spine, as well.

I have a gorgeous 4X19" piece of damascus to cut up but Im almot tempted to do more work with clay...theres something about them that is really addictive.

[Andrew Garrett]

There is such great depth there! Look at this picture for a minute and tell me you don't see sand dunes bordering a beach!

Awesome.

[H.T. Ryerson]

Nice Hamon! One of the clearest I have seen in 1095. I would love to know what clay mixture you used- I have had bad luck with mine falling off in the quench.

[TikTock]

The clay was Satinite. I applied it the night before, then left the blade under a hot shop light all night. I think that kept the blade at 1-200 degrees and fully dried the clay. The next day I sealed a few cracks and torch cured them.

During HT, I made sure to not let the edge get to critical before the clay was fully at temp. I waited until the clay was equal temp as the blade. After a few Q&A session, it kinda *clicked* for me. I had not realized the function of the clay was not to keep the spine cool, but to keep it hot. I practiced my quench a few times and Got it in there under .5 seconds, since the nose for 1095 is soooooo fast.

I had clay fall off in the past, but i had never let it fully cure before HT. Perhaps that was the trick. Ive also heard using borax before applying clay helps keep it on.

I did an edge quench, then held it there until the spine was cool. With the clay intact, this took a LONG time and I am sure lifting it early woudl have ruined the blade because that clay kept the spine glowing red for some time, so i kept slicing through the quenchant for that time.

In theory, I would next time keep the clay a little higher on the blade to move the main transition line up. I would also take an extra 3-4 normalizing cycles to minimize some of the banding effects I see between transition zones.

Under good light, I can clearly see at least 4 different hardness zones. The main edge, a crystallzed structure along the main line, some banding wootz-like effects up to the second line, then swiring mixes of that wootz-like pattern and smooth greay unhardended steel at the very spine.

[Robert Mayo]

Great looking blade the hard work paid off. Thanks for explaining your procedure.
Keep up the great work, i still want to see it finished.

Bob

[H.T. Ryerson]

Originally Posted by TikTock

The clay was Satinite.

Thanks for answering my question! I actually have a tub of satanite that I bought for that purpose, but it is in dry powdered form. Do I mix it with water? How much?

[rhrocker]

I know you're proud, congradulations! Every great once in a while, we all deserve to have something fall into place at the right time, right place. I believe that the clay will leave the spine cooler than the part not coated.

[circlepknives]

Fabulous Dave, that Hamon is a thing of beauty! Keep it up

[TikTock]

Originally Posted by rhrocker

I believe that the clay will leave the spine cooler than the part not coated.

I'd like to talk about that. In my head, I thought the same as you, but after talking to some people and seeing it in the dark, i am fairly sure it is the opposite. When I HT'd that clay was glowing bright red, and the steel below it was visibly the same color. I purposly lowered my pressure to soak until the clay was also at critical. I think that is key. When I then edge quench, that steel in the oil drops below the nose in a tiny fraction of a second. Now picture that like a giant cold front on the steel, traveling up toward the spine. Normally a line will form around the quench line as the steel above cools slower. It is the same in this case, except enhanced since the clay will actually keep the spine hotter, longer. That spine stayed glowing red under that clay for longer than any blade i've done without clay. You are evenly heating the spine in an uneven pattern, so the heat retained in that pattern under the clay meets the colder quenching steel and in general will match the perimeter of that hotter pattern of insulated steel where the steel changes compositon....


At least....in my brain thats how it works......someone who knows for sure, please set me straight......

[H.T. Ryerson]

Actually I am pretty sure that in the traditional method, the entire sword was quenched. (the curved blade of a katana would be kinda hard to edge quench desu ne?) I think you might be on to something though because edge quenching in combination with the clay seems to have given you an awesome hamon! I am gonna try that myself on my next attempt.

[AUBE]

looking good!

what are you using for an etchtant? ive noticed when i used straight ferric chloride for short etches(10ish seconds) it took many etches to get detail to show up but when i went to using 1 part ferric chloride to 2-3parts water and etching for several minutes at a time it seemed to bring out more detail even after polishing it down quite a bit.

[TikTock]

Im using 3 to 1 etchant, 20 second etches....I didnt want any real surface etching to a depth, but rather a smooth finish with variations in grain.....still didnt pull off what I wanted but Ive got 8 feet more stock to burn!

Btw...satinite was a slurry....nothing exact....just a stiky goo....
Thanks All!

Pics of the final knie iwll be coming in a week or so...filework...nickel silver bolsters....ironwood burl....

[hammerdownnow]

tick-tock tick-tock tick-tock.... times a wastin'....don't get in a hurry now. Get out those stones and bring out that nice frosted hamon line look. By next week you should just be finished polishing that one.

sourse of pic(click)