Canada's Sharpest Lefty
Yeah, if he said he did it, I believe him. He's been nothing but great to deal with and comes across as an honest and driven maker.
Now, whether or not differentially heat treating any kitchen knife is beneficial is, in my opinion, up for huge debate.
i think we can all agree that it's cool, though.
Originally Posted by Lefty
Canada's Sharpest Lefty
Yup, I put it in the same kind of category as damascus. It looks cool, and is another way for a maker to display his skills, but the actual benefit of such skill is likely none. BUT, I will say they have their place and I love both.
The only kitchen blades that I can see really gaining anything from differential HTing are meat cleavers (force used for many tasks) and (if a maker could zero in on the hardness/durability of a portion of the blade/edge) the third on the blade/edge at the heel of a deba. Now that would make me happy to see!
Thomas H. is a very smart and talented knife maker. The guy knows a lot about steel also.
I don't think that you can get an optimum heat treat and a hamon in stainless at the same time though. My guess is that he uses a torch to achieve the hamon.
Phil Hartsfield was supposedly getting hamons with A2 (Air-hardening). No idea how he does it, but they don't seem faux.
With conductive heating/cooling, I guess hamon is possible albeit not practical. My newb hunts for stainless hamon would be:
Develope a stainless heat-equation for a specific blade params, write a simulation prg for conductives size/location/intensity varying temperatures & times. Most simplictic be 2 conductive plates (perhaps silver with platinum contact) soldered parrallel heel to tip seperated by a narrow insulator, torches + liquid N for thermal. Reckon lot of tries & errors before achieve a reasonable/usable diff HT hamon blade.
I was aware of the Haslinger knife, but the original question was about the attractiveness of the hamon, and the "clay-type" hamon would never work using traditional methods. I will be clear by saying that traditional methods for a temper line or hamon do not work. There are other ways to achieve a similar effect. I said that a utilitarian temper line is "difficult" but never said impossible. Also the original question was about avoiding patina to maintain the beauty of the hamon, but as I said corrosion resistance is reduced for the softer spine. Maybe this would be attractive, but not the same thing.
I'd try inductive HT first.
Originally Posted by bluntcut
I picked up 3 new knives from Heiji today (wowowow etc. Will post some first thoughts with pictures after i have had a chance to use them more, going on vacation Wednesday for a few weeks)
Here is a (small, would post better but this forum won't allow it unless I upload to external site) picture of the edge on the Suji.
Is this semi-stainless knife heat treated in a traditional traditional way or is the hamon achieved some other way?
Edit: Reading Jons reply below I need to do some more googling :-)
thats a clad knife... the line is the lamination between the softer cladding and the harder core