Views last month

Donnerstag, 16. Oktober 2014

New and baaadass Seax;-)

 During our recent hammer - In I forged a blade out of ancient spring steel I found in the woods, the same I forged the recent integral from. I tried again the hollow-forging technique that gives a good compromise between strength and cutting prowess. I look at it this way: Many bushcraft knives, and even famed ones like the Ray Mears design have a great ability when whittling or doing surface cutting, but tend to be not so good when you actually have to cut through something. This is due to a Scandi grind that does not even reach the first third of the blade and therefore acts more like a wedge than a knife. I am personally very fond of a kitchen knife of Syrian provenience in my possession, which has a blade that is at the thickest 1,3 mm in the spine, AND has a convex bevel. It is made of Wootz steel which means you can actually chop antler with it with no harm to the blade and to a lot of things I would not do to a veritable production bushcraft knife. Better knives for cutting through things are the Puukko variety, including the bush prowler by Ilkka Seikku

This led me to some deeper and weirder thoughts. The strength of a blade lies in the thickness, of course, and the edge geometry, for sure, but in production knives, this is often due to liability issues or production requirements. Hand forging, when done right, is a thermomechanical grain refinement, resulting in a tougher steel structure. If you then take a steel suitable for the task do not mess up the heat treatment you end up having a very high potential in a blade. Now I have long obstained from hollow grinds, even if I like them for the cutting feel they induce, but always was a bit suspicious because there is a profound lack of material where you want it most in a "tough" knife. But I am talking production knives, mostly out of 440C or similar steels here. Stainless steel now has comparatively coarse  grain structures (when compared to high carbon steels with no alloying or tool steels like 1.2442, 1.2842 or the famed 1095 or 15N20 steels) due to the chromium carbides which are relatively big, and most production knives with a hollow grind are laser-cut and ground into shape, not forged, to day. Normally, this would not be a problem at all, but I am talking extreme use and a hollow grind here. If you dress a rabbit once a year and use it for snacking and light whittling tasks you can be more than glad with a 440C production knife. But, when forging, I like to push my personal envelope a bit. So I took this steel which consists of iron and carbon (0,75%-0,95% estimated), and which has seen a hundred years of cold-working until seeing another 50 years of lying in summer and winter temperatures from 40 to -20° Celsius, and was very scrutinous about my temperature window and the heat treating and forged it hollow over the horn of the anvil (Blimey, have to make a tool for that!;-)). The blade is selectively tempered. The spine is a brutal 6mm thick, but that´s about it, it radically tapers to 2,5 mm and then to 1,5 mm in the middle, becoming a moderate 2mm above the edge. The edge then is set high to make a wider grind line (messed it up a bit, I must admit), and the angle is just 20°. I estimate the hardness at about 60-62 degrees Rockwell, gradually fading towards the spine (three quench lines). The tang is almost as wide as the blade at the transition towards the handle, tapering to 5 mm with just the last cm of it being filed down to draw the butt-cap in, the handle is elk antler because it has no marrow which might compromise stability. To compensate for the lack of material at the transition, the handle is wider at the bolster and a ferrule out of copper is fitted. It is glued with a dual-compound glue that hardens up to 370 N / mm² tensile strength. Only then is the butt cap glued on and the tang peened over. 

 I have, by the way, peened it over in a very unprofessional way which qualifies aas gross abuse. Positioning the tip of the blade at a right angle to the grain of dried and knotted heather wood, I hit the tang with a ball peen. I then levered the tip out, and it was only slightly bent, not broken. I hit it with the peen to straighten it up. I then thought alas, it´s too soft and tried the tip with a file. It slid off, taking off but marginal shavings. This steel is awesome, and I hope I can find some more! I the tried to slam it against the vise to provoque breaking off what wanted to break off after this, but it didn´t, even after this degree of abuse. SORCERY!;-)
 The shape of the handle and the blade looked awkward at first, but it´s growing on me fast. The tapered handle makes for a secure grip, and the blade has a balance that makes you want to whittle and cut.
I have chopped antler with it and carved funny curves out of freehanging newspaper afterwards, opened tin cans, made the sheath with just this one knife, and cut thin pieces of salami, onions, cheese, apples, and fresh bread. I whittled with it, pryed with it, dug with it for roots, and it does it all. I guess I have created a monster;-). It´s not eloquent, and many people would not like the raw appearance, but to me it has a history and it performs better than many of my knives and certainly better than most production knives I own. I guess, mission accomplished, so off to the toolmaking with me;-)

Keine Kommentare:

Kommentar veröffentlichen

Now go on, discuss and rant and push my ego;-). As long as it´s a respectful message, every comment is welcome!

Beliebte Posts