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Alan Longmire

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Everything posted by Alan Longmire

  1. That looks kinda wrought-y, try forging one. Start at near white and forge to low red. If it goes stringy or crumbles, it's wrought.
  2. If your O/A set has a large rosebud that'll work, but if you're building a forge propane is the way to go. I have used a big cutting tip to heat axe edges, you just have to keep it moving. But to get the eye uniformly hot a rosebud or a forge would be better.
  3. Yep, respirators when grinding. Plus a good fan blowing the dust away. Always safety glasses, too. What kind of equipment are you using to shape the handles? If you're just using files and sandpaper you still need to watch the dust. Search this site for the word "Decalescence." It's a visual proof that the phase change has taken place on a rising heat, and means even if you're colorblind you can see exactly when the steel is ready to quench. Gotta be in dim light to really see it, so keep the forge barely running. You do not want to blast through the right temperature. Also look up "normalization." This is to refine the grain and improve toughness. The steel as purchased is annealed, and normalizing will distribute the carbides for better edge holding and toughness. Finally, 400F is too hot to temper for a small hunter, in my opinion. With 1084 I'd stay at 350F. This will give better edge-holding without being too hard to sharpen.
  4. Nick and bend ought to do it. Not being a west coast guy, I don't know much about the sources of materials other than by 1890 much of it was coming in by train from places like Chicago and other greater rust belt cities.
  5. You make a drift (mild steel bar the shape you want the eye to be, tapered so you can drive it in), then you heat the head to a nice bright yellow and use the drift to reshape the eye. Then you'll need to redo the heat treatment, one edge at a time. There's a LOT of info on heat treating here, just look around.
  6. Test them anyway, the Globe Elevator nails are from 1888 and they're wrought. But a lot depends on where it was made and the prevalence of wire nail machinery. Wire nails appear in Europe in the 1840s for furniture work, but didn't catch on in North America until the Great Chicago Fire in 1871. The local steel mills had invested in wire nail machinery right after the Civil War, the local sawmills had been trying to introduce dimension lumber to speed up construction since the 1850s. After the fire these two things plus the need to quickly rebuild several thousand houses resulted in modern framing, since it's so much faster to just buy some 2x4s and nail them together than the previous way of timber frame joinery. Thus for archaeologists, we tend to date a historic house site by the type of nails, with wire nails being generally post-1870. This can be misleading, since the machinery was expensive and mild steel cut nails worked fine. So places like eastern Tennessee where I live used cut nails commonly well into the 1930s because the local nail factory had nail cutting machines and it cost more to ship wire nails in from elsewhere. I suspect the city where Geoff's grandfather worked was the same. Just saw Billy's reply about the black: nope, that just means the wood is acidic. Do test them to see, though! Some people requested wrought because it was believed to be more resistant to corrosion.
  7. What Geoff said. They're machine-cut nails, introduced in the 1790s, but only fully functional (machine cuts and heads in one go) by 1815. Prior to around 1840 they couldn't roll a sheet of wrought wide enough to cut with the grain, so early cut nails can't be clinched. They snap along the grain. This being the case, when Bessemer steel hit the market in the late 1850s, nails were among the first applications. You get wrought cut nails up into the 1880s, but they're not common after 1860.
  8. Wow, Jaro, that whole piece is fantastic! What's that handle wood? Yesterday I got the blades and springs last seen on the grinder chuck ground, polished to 400, and ready for HT. If my co-conspirator can make it I intend to HT next Saturday. Today I built a rather large firepit. Doesn't look that big here, I just wanted to show Spring has sprung what with the mulberry tree in full bloom... It's about 3.5 feet by 6 feet, or 1.1m x 1.9m rectangular. It's also in need of three more bricks because I miscounted somehow. The idea with the higher walls on the left and lower on the right is to use the left half as a general bonfire area and the right side for cooking. Next step is to make a tall tripod to hang a 28" diameter (~70cm) schwenker-type grill to be forged from heavy steel. It'll be heavy enough to support a griddle or a stewpot, with a trammel up top to adjust the height above the coals. Not as groovy as a Chilean or Argentinian asador, but easier to make by forging and with my minimal stick-welding skills.
  9. Gary: Nice! Jerrod: Thanks! Now then, what are your thoughts on 52100 and temper embrittlement? I have done a lot with O-1, 1095, and 1075 in the "blue brittle" range for springs with only a couple of failures. That chart makes it look as though the correct folder spring temper for the stuff is right at the top end of that. Also, yay me for estimating the number by extrapolating the curve.
  10. Nice! Wider than the ones I get. How wide is your bandsaw blade? It's best when doing this to cut the teeth off and then trim both steels to the same length and width. Helps get a good weld.
  11. That is a truly great hamon!
  12. A quick search didn't show anything for 52100 spring temper, but this table from Knife Steel Nerds https://knifesteelnerds.com/2019/05/13/how-to-heat-treat-52100/ suggests that 500F should do it. You want a spring to be around Rc 45-50. But you want to avoid the range between 500F-700F for low alloy steels due to potential for temper embrittlement. Try it at 500, and if that's too stiff/brittle try it at 750F. If that's too soft, try pushing the edge at 525F and grind the spring thinner where it needs to flex.
  13. Yes indeed! You want a full spring temper on the springs, so you have to research that for your steel. With O-1, I temper the blades at 350F and the springs at 700F. With AEB-L I temper the blades at 320F and the springs at 1145F. Stainless is weird stuff... each alloy has its own peculiarities. AEB-L hits a secondary hardening around 950F, so you have to go a bit higher to draw it back. Luckily there are charts available for these things.
  14. Ooh, that'll be nice! Love that half-octagon barrel. What caliber?
  15. Got that "sold my last stock, gotta make more!" bug. Plus I'm showing a local guild member how I do it. That's AEB-L on the Beaumont Metal Works surface grinder attachment for KMG.
  16. Galvanic corrosion is not generally a problem for knives over a lifetime or ten as long as they're kept dry. You only really see it archaeologically, where the iron/steel will be gone but the brass remains. Takes at least a hundred years and a damp acidic environment. Probably not good for a saltwater dive knife either, but again as long as you dry it off and oil it it'll be fine.
  17. I think 5/8" solid or schedule 40 tubing is fine for that weight at that distance, but I'd put a tong rest (aka a sawhorse) by the quench tank so I could rest the tongs on that while I dump the charge into the tank, if that makes sense.
  18. After reading Dan's excellent reply, I got to thinking about pouring shanks and pipe handles. Lo and behold, this popped up: Now, I know your "crucible" isn't going to have molten metal in it, and being parallel-sided adds complications, but I think you could weld a couple of lugs on the sides to grip with a similar shank with the arm that grabs the lip of the crucible. Heavy flat strap steel, say 3/8" x 1", 1/4" x 1" would be very safe for the jaws of the shank. I assume you'll have a support for the tongs when you dump the charge into the quench? I do like color case hardening... Are you using aeration and a brine quench?
  19. An understatement, but think about the theme...
  20. A buddy of mine sent me this. I have a few things to say about it. First, you have to admire the skill of these guys. They are very good at what they do, as far as manual skills. Second, now you know why cheap Pakistani knives won't hold an edge. I bet we weren't supposed to see them grind the blade past blue after HT... That said, somebody has provided them with excellent tooling. That rolling mill, for example, and the punch presses, rotary shears, and assorted other power stuff. I was impressed that everyone still had all their fingers and eyes, though. Other safety note: do not try their etching process at home. I was wondering if the real Laguiole folks knew about this, and turns out they do. https://www.laguiole-french-knives.com/en/content/10-how-to-recognize-a-truth-laguiole-knife Please note I am not making fun. These guys work hard and are very skilled. They've come from generations of metalworkers, after all. They just can't afford all the safety stuff we take for granted, and lack a bit of the more technical metallurgical knowledge we have available. Or just can't justify it at the price point they need to profit off this stuff. That's something we struggle with as well, unfortunately. I just though you guys would appreciate watching the operations, and be envious of the equipment.
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