A client recently asked me to prepare a Barge for a SEAL. And as you know, I'm a bit behind on my polishing. Right now I would like to explain the tip and why it's modified.
It is quite common for hard use knives to have their tips broken. If it's a jackknife or hunting knife, I usually just dress the spine down and blend the bevel into the new tip. My guess is that a SEAL plays hard with his toys, and I wanted to enhance the tip.
As you know the tip of a knife is tapered in two ways. First, look down at the top of the knife, the blade blank is wide by the handle, and it narrows towards the tip. This is known as "the distal taper."
Two, if you want the bevel to be uniform with the back of the edge, you're actually thinning the tip from the side. In most cases, the knife will last forever, or I can fix it.
But a SEAL doesn't often find a working togishi in the field. If he breaks something it's gone. So I had a lame idea that works.
I cut the bevel to uniform specs with an Atoma 140, just like any other knife. Then I take the knife over to the obsidian block and cut the tip bevel off about 5/8s of inch back. This cut touches the shinogi line (that's where the bevel touches the cosmetic portion of the knife) and blends into the existing bevel I just cut.
Then you flip-snip-flip snip until you've made a new tip which matches the existing bevel. Why, you might ask.
The edge of any knife is the thinnest part. By removing the factory tip, I have "moved" the tip into a thicker portion of the blade blank. Granted, the prying tool on the end of the handle will take a pounding, but the SEAL might have to cut something tough--like the combat boot of a wounded compatriot.
This is putzy, nerve wracking work--the middle of the knife was never supposed to be the edge. But it's worrisome to send a knife to a SEAL on Monday and get it back on Wednesday with a nice note saying, "I broke it."