Knife Deep Dive: Rockstead REN ZDP

Knife Deep Dive: Rockstead REN ZDP

The Ren is one of the newest models Rockstead has to offer.

This is a ZDP-189 high carbon, powder metallurgy, stainless steel blade with a hardness of approximately 67HRc. As with all Rockstead knives, the exact manufacturing process is not shared with the world, although we know their eight-person team uses proprietary machines in their factory to achieve this extreme level of precision. The exact hardness is tested on each model to one tenth of a Rockwell hardness point (!) and is noted on the 'birth certificate' that comes with the knife.

This is a blade in the shape of Tanto Honzukuri. This means that the blade is completely convex ground, without the use of a micro-bevel to maximize cutting performance. This one is inspired by the Japanese sword. With this model they have succeeded in doing this in a tanto form. So you have the iconic profile of a tanto, but with the superior geometry of the convex Honzukuri cut.

The blade is then given a mirror finish to not only look nice, but also to stay sharp longer. On a microscopic level, the blade finish of a Rockstead knife will still appear smooth, while blades from different manufacturers will appear coarser and in some cases even serrated or serrated. So why does a mirror finish stay sharp longer? A rougher finish is more susceptible to surface imperfections. These imperfections are more likely to lead to bending or breaking of the apex, resulting in premature damage to the edge of the blade.

The handle of the Ren is made of precision machined titanium. As is the case with more Rockstead folders, this model is locked via a frame lock fitted seamlessly with a lock bar insert of the correct hardness that sufficiently minimizes the wear caused by friction due to the extreme hardness of the blade steel. The snug pocket clip is also made of titanium. The other side of the handle is made of 3D-milled carbon fiber, but despite the difference in materials, it doesn't come across as unbalanced at all.

The Ren is a wonderful new addition to the Rockstead pocket knife range. Not only does it look high tech, it's high tech.