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Aiden CC

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Aiden CC last won the day on April 8 2018

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About Aiden CC

  • Birthday 04/01/1998

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  1. Looking closely at the video again, I can see what you mean. I think he is left handed, he says something about it in the video below around 1:20, though through the translation I'm not sure if the knife is meant for a right or left handed person. I'll also look around for more sources on these knives, like all of this stuff, definitive information seems hard to find. A quick google image search turns up mostly knives with grooves on the right with a few exceptions, though most of them are modern replicas which are often unreliable. Looks like it's time for more research.
  2. I might have to add another knife to my schedule! If I understand the video/your description of the uses correctly, these knives are slightly concave on the left side, and slightly convex on the right side? I got turned off of that shape when I was making my first Sakha knives (though the other "handed" version), as the exaggerated convexity on the forge-scale bearing modern versions just doesn't cut very well (at least in my experience with the few knives I made that way). Having the bevel on the right seems to help with boring (at least for a righthander), since you can tilt the knife a bit and twist clockwise to cut chips instead of painfully scraping out dust and possibly chipping the edge. I'll check out a more of his videos too, I watched a bit of the stuff recommended from the sheath videos. I really like these multi-purpose knives and the depth involved in learning all the different ways to use them.
  3. Got the Sakha knife and one Komi knife rough polished ready for handle fit-up. Pretty labor intensive to polish the hollow side! It took twice as much sand paper as the flat side. You can see the relatively small depth of the hollow. It's enough to make sharpening easy, but not nearly as much as on a lot of modern versions. I decided to test out the boring capabilities of one of the Komi knives. I think if the knife was dedicated to this it would make sense for it to be narrower and thicker, since I could imagine damaging the edge on this one if you didn't do it right. It would probably be somewhat easier in green wood. For a more versatile cut-and-drill blade, I would say it works reasonably well.
  4. Some decoration. This knife and the Kokemäki style puukko are tempering now.
  5. Finally got around to finish grinding those three yesterday. The hollow on the big Sakha one was tricky. Now the blades just need some hand work. I also forged a handful of puukkos today. The “copies of copies” phenomena also happens with these knives (though many modern adaptations are beautiful and functional in their own right), I’m trying to base these on examples from the Finnish national museum. Forging so many asymmetric knives admittedly has me a bit out of wack! I can usually crank out puukkos, but I’m not really happy with the forging on these ones (they came out too wide and the bevels aren’t very crisp). Should come out in grinding, but I’ll probably forge a few more to get back into the swing of it.
  6. I actually wouldn't be surprised if there was some martensite formed, even in a shallow hardening steel. When you plasma cut mild steel, the heat flow from the cut edge into the body of the piece can be enough to harden the edges (I got impatient cleaning up the super-hard edges of plasma cut parts and decided to look at some samples). The same thing can happen with MIG welding, etc. With the plates being big heat sinks and the force of the press making a good thermal contact, I wouldn't be surprised if a thin piece hardened. I've had the same happen to old spring steel (composition like 5170) with just an anvil and hammer (also god fed up with drilling holes in hard steel, so did some metallography). EDIT: Found the micrograph of that hardened mild steel. This is a cross section of the edge off of the plasma cutter. And this is from that spring steel normalized on the left, and after forging then air cooled on the right (pretty much hardened all the way through consisting of martensite and bainite)
  7. I’ve definitely experienced the warping with asymmetrical blades. My approach has been to use two 2x4s and a heavy weight during cooling/straightening during tempering. On some of his recent work it seems like Alexey has been doing edge quenches in addition to/instead of tempering the spine, which I do know for this kind of knife, as least with steels where it will work. I ended up grinding a slight corkscrew into the big Sakha knife, but I think I can grind/bend it out with some care, hopefully some time tomorrow afternoon. This type of knife is very challenging to grind!
  8. That's a neat trick! I've heard of doing that for old knives that have been sharpened a lot and it's how I've ground the few hatchets I've made, but I can see the benefits doing it on a new knife too (might be trickier for a full flat grind though!).
  9. If there is a board involved it seems like even a subtle radius towards the tip would be helpful to make sure its easy to get the last little bit of meat against the board. With a perfectly straight edge you would need to either have it come down perfectly to the cutting board all at once or pull the sharp-cornered tip through the whole cut. The second option is certainly doable; exacto-knives and box cutters work like this and make very clean cuts, but they have disposable blades. A sharp cornered tip would work, but would see a disproportionate amount of wear compared to the rest of the edge, and unless the whole edge was sharpened down to keep up with it, would likely naturally become a little round.
  10. Garry has it spot on; a curved edge lets you rock a knife on a cutting board. Additionally, having some curve towards the tip helps with slicing on a board since you can have a tangent contact to the board. Also, an edge which starts out dead straight is liable to become concave with sharpening, which could leave little uncut parts in the food you're trying to chop, especially with vegetables with skins or thin leaves. That being said, there are kitchen knives with essentially straight edges (such as many Japanese nakiri and usuba knives). Their edges are straight because instead of rocking, they are pushed diagonally through food and contacting the board more or less flat.These knives often have a little bit of curve, but they have much straighter edges than western kitchen knives. Hope this helps!
  11. I'll have to look into that! In the past I've done research when I wasn't able to work on knives, but now I might be able to do both. I finished the leuku and it has been soaking up tones of linseed oil. I'll take better pictures at some point, but with so many knives in the works, I'll wait until a few more are done. I've tried it out a little bit, and the geometry is definitely an improvement over the last one. The fullering on the short Sakha knife and the pre-ht grind on the other. The forge-finish fuller that a lot of modern versions of these knives have seem to be somewhat a-historic, with old originals being either flat or hollow ground on the right side. In this case, the left side is flat ground and will have a secondary bevel with the right side being ground on an 8" wheel. The shorter one after being straightened and having the second groove chiseled in. Both the fuller and the groove need to be deeper that you would think they should because they were done onto an as-forged surface. It's tempting to grind the surface clean after bending, but if you do that it will be crowned when you straighten it (ask me how I know ). The geometry of the chisel is also important; if the included angle is too high, you end up with a groove that is too shallow and gets ground out. If it's too low the groove won't get wide enough and the chisel will dull faster. A generous radius is also important so you can "walk" the cut up the blade. The plan is to grind this one then do some file work on the spine and go to heat treat.
  12. I've thought about doing something like that. I've done an one and a half independent studies on heat treating and metallography, and also got a bit of credit and reimbursement for materials for making punches and drifts so it's definitely within the realm of possibility. It is notoriously hard to get any kind of humanities credits for an independent study at my school because they are a graduation requirement, but I could probably get 1/2 a class or so of typeless credits. It's a little tricky at first (filing the groove to a uniform depth is deceptively difficult), but it gives very clean results. It seems like it has been used for at least 100 years to make this kind of fuller, possibly longer. Made a bit of progress on the Leuku: Here it is after 120 grit plumber's tape. I may have positioned the tang poorly in this block and sanded off all of the interesting part, but I guess I'll see once I get it to a higher grit.
  13. Got the two little ones hardened today and did some forging on my last day before online classes start up. Two Sakha style knives. The big one will be hollow ground on one side and flat on the other (like Japanese single bevel knives, but with the opposite handedness), the little one is curved so I can file in a fuller before I straighten it and chisel/file in the other ornamentation. I'm realizing this is a lot of knives to have going at once, but honestly I'm a bit scattered at the moment. Plus, I'm going to need a lot to work on to fill the extra time for the next few months.
  14. I'll have to give some of that a read. Scrolling through it, I think at least one of the drawings looks familiar. A little while ago I managed to trace back copy-pasted text/images to this article (http://ilin-yakutsk.narod.ru/2002-1/56.htm) which seems fairly academic and has a list of sources as well. Definitely leaves some details out that would be helpful to a knifemaker, but it seems like that's often the case in pieces by historians/ethnographers/archaeologists.
  15. Made a bit of progress on these. The having a mild steel tang made a huge difference in the ease of riveting. The blade never slipped in the vice, the rivet didn’t crack, and it took about 1/4 of the time. Definitely worth the little bit of extra effort to forge weld it on. Got these ground and filed in the shoulders. This is definitely a unique geometry. I may test out how they are at drilling by using them to make their sheaths/the one for the leuku.
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