For the past year now I've been using the TOPS B.o.B. Fieldcraft as my belt knife. This isn't a knife review, as there are plenty of better places to get that type of information. Needless to say that I'm happy with the knife and it performs.
I was lucky to be introduced to this knife while it was still being developed by the Brothers of Bushcraft. My first exposure to it was when I spent a week with Mors Kochanski, where Caleb Musgrave was field testing the prototype.
The prototype of the B.o.B. Fieldcraft
At this stage features like the bowdrill divot and the shango notch hadn't been added yet, but the blade and handle design were there. I was one of the lucky few who actually got to handle the knife before it went into production and even held audience as Mors himself critiqued the knife. Needless to say I was impressed as I was a first adopter.
Of course as I've stated before, I'm not a fan of epoxy coatings on my knife and so I stripped it. This time however, I wanted to save the laser engravings of the logos, so I decided try my hand as acid etching.
I took cues from this process, but modified it to a smaller scale. I coated all of the exposed steel that I didn't want etched with a clear nail polish, which is cheap and works to protect the exposed areas from accidentally coming into contact with the acid.
Rather than immersing the whole knife into a tank (which I don't have) with a whole load of etching solution (which is wasteful for only 1 knife) I built up a small retaining wall around the area of the logos I wanted using hot glue. I built up the wall layer-by-layer, allowing sufficient time for each to cool, so I could stack the next. The etching solution I used was ferric chloride, which it typically used to etch printed circuit boards (PCBs). This isn't something you can walk into a hardware store, so I sourced it from a local electronics hobby store.
To perform the etch, I filled the small reservoir with the etching solution and let it sit on the blade in 6 hour intervals. After the 6 hours, I would rinse the areas with water while scrubbing the logos with an old toothbrush During the etching process the material exposed to the acid turns dark, but while wash away with scrubbing to reveal the fresh material underneath. To achieve the level of depth I wanted I repeated this process over two days.
When I was satisfied with the results I removed the protective nail polish with acetone and began stripping the epoxy coat the same as I did for my ESEE knife.
The stripping process
The resulting etch and polish turned out really well
The final result, shown with my custom made leather sheath