Engnath question..

IMHO, it deserves to be professionally polished and then mounted to show how nice it really is. I don't see why it should be kept unpolished.
 
There are some issues there. First of all, he doesn't know how to accurately describe it. Nobody "cryogenically tempers" as there is no such thing. You can use liquid nitrogen to assist in the hardening process, by converting any retained austenite to martensite.

Secondly, by looking at the oxidation on that blade, it looks much more like an air hardening steel than something like 1050 (that I think Bob used for most of his Japanese style blades).

That might just be an issue with the pictures though.

BUT, if it was an air-hardening steel (I can easily imagine Bob using A2 for a blade like that) then it doesn't matter how great of a polish it gets... it will still just be a nicely satin finished blade.

OR, so I think ;)
 
Here's some info from Bob's site..


SPECIFICATIONS
Steel - 1045-1050 with an edge hardness of RC 56 to 58. Body hardness is from RC 42 to 46.

Finish - flats of the Vee grind, 220 grit, back 120 grit, guard notches ground square, cutting edge is belt sharpened (and dangerous).

Production - flat ground from new bar stock.

Hardening - individually clay coated to create the edge pattern, heated in a slot top gas forge and water quenched.

Weight - A standard 29 inch blade of average width will weigh about two pounds, two ounces. These are 34 mm high at the Machi and 24 mm at the Yokote.

Edge pattern - Notare is standard. We have a lot more control of the pattern on shorter blades. With long blades. you pretty much have to take what you get. Tips generally have a turnback, and there will be some small hard spots along the spine of the blade.
 
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