Question About Clay And Making A Hamon....

[Zombie_Steel]

ok so am new to this site so hi all! second i also just started making knives and have made about 9 of them so far and have learned so much from each one. watched a lot of youtube and asked a lot of questions when i could.

getting into japanese style knives (not making them the traditional way!) but am very intrigued by the use of refractory clay in the use of keeping the spine soft while hardening the edge. no i don't have a pottery shop close to me, but i like to use what i may have lying around the house. i happen to have some clay bricks that i used for my forge, (albeit not totally efficient!) but was wondering if i ground up those bricks and added some water to make a paste if that would also give me the same affect as using refractory clay? or maybe even using wood ash mixed with water for the same purpose? i am working on a tanto now and will be soon ready to harden it.

also it would seem that once the blade is brought to critical you DO NOT normalize the blade, but instead quench it cause the clay retards the cooling process of the spine. do i have that correct?

 

[i4Marc]

Hi ZS,

I am fairly new to making knives myself so I will let others offer the technical input. As far as the refractory clay goes it should be fairly easy to find online. Here are a few to get started.

http://www.budgetcastingsupply.com/ITC.php
http://www.bigceramicstore.com/tools-supplies/brands/itc.html
http://usaknifemaker.com/forging-to...172-173/itc-100ht-ceramic-coating-1-pint.html
http://www.anvilfire.com/21centbs/products/ITC_forge/

If you don't want to order online and want to try something else you can try your local Lowes or Home Depot. Look in the department where they have grilling supplies or in the paint department in the caulk section. Look for furnace cement. It comes in a caulk tube. It withstands temps up to 2000 degrees. I have not tried it yet for differential hardening so I don't know for sure that it will work but I think you may have better success with this route rather than trying to make a paste out of ground up fire bricks. Good luck.

 

[Wolf Creek Forge]

Ive used refractory brick morter that you can get from TSC locally.Just thin it down with water..The keys with hamons and clay are Less clay,less heat and less etch more polish... Thats what has always worked well for us..If you have temp control you can get a nice hamon without clay..

 

[Stacy E. Apelt - Bladesmith]

Welcome to Shop Talk.
Filling out your profile is a good idea. It may let a nearby maker offer you some help or materials. It also lets us tailor an answer better. The reply to a high school senior who wants to make a knife is different than one to a retired machinist.

Hamon and yaki-ire ( the quench to create a Japanese blade with a hamon) are regular topics here. Put this search engine in your browser:
http://www.google.com/cse/home?cx=011197018607028182644:qfobr3dlcra

Use it to look up any past subject on BF.

There are a lot of refractories used, but I think the most accepted is satanite.
Walter Sorrells has a great DVD on making hamon, and others on making Japanese swords. These are all well worth owning or renting.