What Is Acid Etching And Why My Axxis Will Have It



Traditionally, most knife companies use acid etching to enhance the visual aesthetic of their differential heat treatment, or to distinguish different layers of steel in a Damascus blade. It looks good, but provides little function. Fortunately, Bone Daddy Blade WerX isn't like most knife companies. And while we always strive to make our tools visually appealing, we would never make a design choice based purely on looks. No; we believe that form should follow function. And so it is in our decision to acid etch every Axxis.



Acid etching found its origins in the renaissance when artists would use the process to emblazon armor and weapons with fantastical designs. Today, the process is far more mainstream, and can even be done right at home. There are many effective ways to acid etch a blade ranging from common household vinegar, all the way up through sulfuric acid. However, the specific acid selected depends on the metal being etched and the desired degree of pitting one hopes to achieve. The etching itself is the effect of a chemical reaction between the steel and the acid. When brought into contact with each other, the result can be a light discoloration of the metal, or even heavy pitting depending on the duration of the chemical reaction. As it pertains to the Axxis, we've opted for long exposure and heavy pitting.



But why induce heavy pitting? Isn't that one of the adverse side effects of rust and doesn't it expose the metal to further corrosion? Yes, this is true, especially if the metal is not coated with some protective oil, sealant, or finish following the etching. However, our reason for pitting the steel relates directly to the finish we have chosen, Titanium Nitride (TiN). Through a process known as "vapor deposition" a chemical process bonds the TiN to the steel on a molecular level, resulting in a surface coating that can be more than twice as hard as steel. If the steel has been heavily etched/pitted, the surface area will be far greater, thus creating a greater substrate upon which the TiN may bond. Unfortunately, there is no coating that is 100% invincible, and a TiN coating can still be scraped and damaged, especially if your Axxis accidentally hits/scrapes a rock.

Which brings this discussion to the true purpose of the acid etching/pitting... In the awful, unthinkable event that you drop your Axxis or have a chance encounter with a rock while processing wood, the resulting scratch or scrape will be virtually imperceptible. Why? Because the micro pitting along the surface of the tool creates tiny "peaks and valleys" in the metal. And, while it might not be immediately apparent, the greater percentage of total surface area exists in the valleys, not on the peaks. This means that rocks and other hard materials will skip along the peaks, leaving the TiN coating unscathed in the valleys below, and keeping your Axxis sexy for years to come! Looks might not be everything, but in this case they certainly help!