Hamon goop

[Charlie Mike]

I tried some DAP brand fireplace mortar last night and it actually etched into the steel during HT. Since I have to send out for surface grinding, this is no good. What is the proper goop and where do I score some?

 

[samuraistuart]

CM, I guess the "Go to" stuff for hamons would be a product called Satanite. I bought mine from High Temp Tools. I have also heard that the black Rutland's furnace cement, that you can buy in a caulk tube, works well, and can be had from Ace Hardware, True Value, etc.

Some guys make their own "goop"! With my luck, if I tried making my own, it would put the hamon on the spine instead of the edge!

 

[J W Bensinger]

If you want to go really old school you can do a fine wash of clay over the whole blade and then use a mix of clay, ground charcoal, and ground up straw or hay (as a binder). It works best if you wrap the blade with a spiral of iron wire both to create ashi and to give the cussed stuff something to grab onto.

 

[stezann]

Are you sure it actually etched into the steel? Isn't it possible that you got scaling/decarb in the bare area and you see the difference between the covered area?

 

[Stacy E. Apelt - Bladesmith]

Many of the fireplace mortar compounds are mostly sodium silicate. They leave an etched surface, and can leave a little lip where they stop. Not a big deal, usually.

I use Satanite with good results.

Why are you surface grinding the blade after a hamon HT? That seems counter to the idea and process of developing a hamon.

 

[Charlie Mike]

I'm grinding in the hardened state to prevent warps. I'm hardening unground blades. The temper line still appears.

 

[Dopic1]

I have also heard that the black Rutland's furnace cement, that you can buy in a caulk tube, works well, and can be had from Ace Hardware, True Value, etc.

CM, I have tried a few Hamons (Few being key word) and have had good luck with the Black Rutlands furnace cement.