Noticed Metal Master has some Shimatani HAP40 blades for sale. Actually look quite nice with the rosewood handles, damascus, and supposedly run extremely hard RC 64-68. Prices aren't that bad but I've never heard of anyone of this Shimatani guy. Anyone have experience with the steel or maker? Apparently HT is everything so not sure if this is a marketing trick to advertise this hard power steel.
I just bought the Shimatani Nakiri in HAP40 from Metal Master. (And joined this forum purely to answer your question.)
The transaction went smoothly, although I did get caught in a Japanese holiday which delayed shipment for a few days. No problem there. The knife was shipped Japan Post SAL with a tracking number. Shipment took about 2 1/2 weeks.
When the knife arrived it had some sticky gunk on the blade. My guess is that it was some form of oil or preservative that got dried out. Stubborn stuff, but it gave it up to lighter fluid.
The rosewood handle was rather brown, not the reddish hue that I prefer.
The blade had a very attractive damascus finish. It is supposed to be clad with soft iron, however I saw no signs of reactivity after use. The blade measured 2.5mm at the spine at the choil (as advertised), tapering down to 1.4mm at the tip...not that Nakiris have a tip. The spine was almost dead flat, save for a small hump about 2/3 towards the tip which was not obvious without use of a straightedge. There were some significant hammer/chisel marks on one side of the blade at the choil, perhaps from forming. Think of ballpein divots. I'm fine with it, and can call it 'character'.
OOTB sharpness was good. The edge seemed to have a 70/30 grind, although who knows if that was intentional. The edge was polished, probably to ~ 5K Shapton level, maybe better. Thickness measurements at the spine are only part of the story because the blade is crazy thin behind the edge. Performance was laser like. Bell peppers, onions, celery all quietly turned to dice. No wedging in thick carrots.
I haven't had the opportunity to take it to the stones, but I see a lot of potential here. I will set a 10 degree bevel (probably with an Atoma 140) and take it up the progression to 1u. Using it with that acute angle and level of refinement should tell the tale of how successful the heat treating was. (Although, looking at the Hitachi data sheets it might be hard to goon this steel up. It's going to either be hard or harder.)
Thus far, I would have to say that this knife was an absolute bargain at $130 + $5 shipping. I can definitely recommend Metal Master. As for Shimatani, since each knife seems to be hand crafted, you might be in for the luck of the draw. I just rolled the dice again for a Yanagiba in Ao Super so I feel confident.
Cheers,
Rick