Jump to content
I Forge Iron

Stainless Sanmai


Recommended Posts

Working on a big batch of sanmai. About 11 pounds worth of sanmai actually. Most of it is straight low carbon jacket steel sanmai, and a small portion was 410 SS jacket sanmai.


All of the billets contain a flavor of German tungsten carbon steels that resemble what's available to Japan from Hitachi.

I've had problems with SS sanmai in the past, but was able to pull through this time. Forged quite thin as well. All 3 knives have a spine thickness above the heel .105" thick or thinner (the small blade is like .089" above heel at spine.

Anyone who has forged SS sanmai, knows forging it thin is quite dangerous as the SS likes to be HOT or the billet wants to break apart.

Heat treated this batch along with some test swatches to check my HT of these difficult steels, with great success. Both the SS and core steel display silky tiny grain, even zoomed in. Core steels are 1.2519, 1.2442, and 26C3 ( not a tungsten steel)

More to come.





Link to comment
Share on other sites

These look fantastic so far.

I attended a recent hammer-in where a demonstrator (sorry, have forgotten the gentleman's name) very quickly nocked out a SS Sanmai billet in well under a minute, not counting heating up, using a large rolling mill.  Of course he had previously cleaned up the stock and done a full perimeter weld, but it was still a pretty remarkable feat.  Two passes though the mill and the billet was completely welded and forged down to usable thickness.  It happened so fast I could hardly even take notes, much less blink...

Link to comment
Share on other sites

He was using an old industrial grade rolling mill, and processing a blank that was about the size that could be used for one or two kitchen knives.  The rolling mill was about the size of a Fiat 500.  I don't think a homebuilt one could be quite that effective.  He just zipped it through the mill twice and it was done.  Anyone who had done SanMai by had was just left picking their jaws up off the ground.

Link to comment
Share on other sites

Here is another one with a core steelcsimilar to Aogami 1 called 1.2442.

This knife is a little different in that the wide bevel is coherent to the forged surface, and will be stone polished. These pictures show the multi-faceted bevel that is called Hamaguri in Japan. I take the edge to .001-.002" on a disc to 220, and then take it into my home where I will begin my process of stone polish. By the time I'm moving into natural stones from synthetics, the edge will be 0" and rather forming a burr.

Usually I sharpen a secondary bevel in but ive had some requests not to. This would be reserved for pretty much only the most serious stone polishers to be practical, as the act of polishing the entire wide bevel is also sharpening, much like sharpening single bevel knives from Japan, except you are forming a burr twice.





Link to comment
Share on other sites


Similar flat grinding, sharpening horizontal wheel systems are available for sale at,

1) Woodcraft stores,


2) Lee Valley Tools.

I am certain that other vendors,  also,  sell similar sharpening, (& grinding),  tools  too.


Link to comment
Share on other sites

This is indeed a horizontal disc grinder. I made this one actually, modelled after the ine KMG makes.

1hp motor with a KBAC VFD for total speed control.

I basically plasma cut out of .250" 1018 plate a motor mount. Install motor, vfd and disc.

I spent around half the cost of the KMG model.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...