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Daniel Cauble

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Everything posted by Daniel Cauble

  1. I'm revising carbon prediction to 1.5-1.6. The grain boundary cementite is thick, but looks less dense than I'm used to seeing once things cross over into 1.6% territory. Of course things will change when I move the concentrations of cementite around, so they will thicken, and I know this based on the thick pockets of dendrites.
  2. Ok let's do this again. I had lost weight before from the mishap so I added a pound or so of W2. Calculating the estimated carbon of the puck and the new steel addition, the carbon was estimated to lower to a more workable 1.7ish. The new puck is 5 pounds. The surface I dendritic in places and the dirty ferric etch shows grain boundary cementite in most areas with pockets of heavier dendrites. I'm estimating carbon at 1.6-1.7% currently. It may change when I mix up some Nital again.
  3. Totally gutted on this puck. My electric kiln I use for REM had something go haywire, and the crucible I reseal my pucks in to bake bled some and as it touched the soft firebrick, it undermined the crucibles plinth inside and the cruciblr tilted and overheated to the point of remelting and pouring out into the kiln. Lol. Needless to say I lost half a pound of steel, need to remelt it. I'm going to add a half pound of W2 to bring the carbon down a tic, and buy new elements for the kiln. Plan to remelt this Friday.
  4. Wrong guy, I mispoke. I contacted that particular archaeologist because I noticed a very high similarity in materials. I then found out he has been following my work already for awhile, so that was reassuring. I was approached by a metallographer to take micros of one of my pucks awhile back. Which reminds me that I need to send that.
  5. I mean it may vary a little bit, but I think I'm in like...10 of the past 12 melts using hearth steel only and yielding between 1.3 and 2%. Once I may have hit 1.3, but the rest have fallen in this 1.6% average area. Then in the recent past I was approached by an archaologist that specializes in ancient metals. The structures I was finding in my steel and showing in micrographs were present in the exact same way as the UHC and cast steel chunks they were finding in Roman slag pits. Interestingly, of the chunks that were in the steel range, their carbon content was also in this 1.6% range. I suspect there is a golden ratio of settings that make chunks of steel with average carbon contents in these ranges if it's all combined. I have been a strong advocate of the hearth and have strived pretty hard to consistently make a UHC product. After toying with certain attributes of the furnace itself, the running of the furnace, everything...changing one thing at a time and comparing what really works and what doesnt...I've just grow a pretty comfortable hand with my way of doing it. In the end the hearth chunk is made up of zones of varying carbon concentrations. If you can maintain a high average, you can take that chunk and remelt it by itself in the crucible. This last run I did things a bit different. Normally the only ferrous feed material I use is derived from the hearth. This time, I didnt have solid chunks of hearth steel on hand to do it that way. Instead I had white and gray cast that was indeed made in the hearth. When I make steel in these ranges, I often get a tentacle or two of about a half pound of white or gray cast that bleeds away from the initial chunk of steel. I suspect conditions are usually perfect at some point in time to maintain a liquid state longer than normal, resulting in liquid steel traveling horizontally across the hearth floor among the charcoal and enriching to the point of cast. I usually break these nodes off the main chunk because they are typically pure cast with no chance of being forgeable (the white cast in the main chunk of hearth steel is forgeable for me because I suspect the lower carbon forgeable steel welded to it gives it the ductility it needs to move ala, forge). So I take this cast and hold onto it to dope crucibles with if I think they need more carbon. Well I needed a puck and happened to have 2 pounds of these cast nodes ranging from white cast 2.1% C, to gray cast, past 3%. Maybe some bits of steel in the mix, but overall cast. With it I added a chunk of crucible steel I made in the past that crossed into the 2.2% range. Then I really wanted around .005% V and added W2 to the melt to bring the carbon level down and add my Vanadium. But yea, I usually just break a chunk of hearth steel I to pieces, add glass and melt. Way too many melts resulting in the ~1.6, 1.7% range to call it coincidence at this point. Sorry for the hijack.
  6. I can make a chunk or hearth steel and break it up all by itself and add to a crucible, and plop out a puck of ~1.6% crucible steel at will at this point.
  7. People use dirty wrought and cast iron as their ingredients. The ancients used bloomery. Oroshigane is cleaner than both in regards to slag. It can also be made to have lower amounts of P than the other two. It's been my main feed material for the past 12 crucible runs.
  8. Nope, blown propane for crucible. Oroshigane or hearth steel has been one of the things that keeps me coming back. The range of product I can produce in a relatively simple furnace is invaluable to me. As far as I know, I've been the only one that sees the ease of using oroshigane as the feed material in crucible steel. To me it's a no brainer. I'm glad to read you are using it the same way. Little to no slag to deal with in the melt vs using bloomery and something I can make in my backyard in an hour.
  9. OKAY. Like puck number 12 or 13 on the books. Melting went great. Carbon calculation based on my experiences with hearth steel seems to be yet again spot on. The top of the puck seems to be around 1.5% C with very thick GBC and below that are sheets of dendrites that i would suspect are in thr 1.7-1.8% range. After some heat treatment carbon should even out across the board. I'll know more after and look at with the scope but I would bet it's probably going to fall around 1.7ish. Pics are crappy ferric etch and cellphone. Have to prepare more nital.
  10. Just looking at the crucible in the 2nd pic I would say it didnt get nearly hot enough. Good job. If it were easy everyone would do it
  11. After that fail I set it aside and did some of my oroshigane japanese blade work. Well i answered a few questions there, ironed out a few questions only gleaned from doing it...and am back go crucible again. I'm avoiding Mn. No Mn addition except for the W2 I am spiking the oroshigane with to add Vanadium which will give detectable Mn in a beneficial range rather than for any depth of hardening. I made a pulverizer to break up my oroshigane. My oroshigane or hearth steel is made a little differently than commonly seen. My way coarsens the grain structure at creation thus making it friable. The oroshigane for this melt is all in 1.5%-3.3% range. Mostly steel under 2.1% with some white cast and bits of gray cast that was made in the hearth. Now I can fit 4-5 pounds in the crucible comfortably and hopefully speed up the melt.
  12. I havent posted my previous puck's forgings, but it was pretty massive and forged out real nicely but found a void, so it ceased. It was an experiment with Manganese, but decided I'm not going to use Mn any more as it hurts the patterning.
  13. Making and successfully forging wootz is more for that pattern than mechanical properties these days. different alloys do different things to the overall pattern though. Also, pure vanadium has a really high melting point and even its oxides.
  14. Thanks Feel free offload equipment like that on me if you dont want it
  15. So I finally decided to combine then 2 bars together the same way I have seen a smith in Japan do it. Where one does the first stage of refinement which is the first 6 folds and combine it with a 6 fold billet made.from a previous sword project. It was done by alternate stacking them as a 4 layer bar and folded 6 more times. I did that with this one. Early etching revealed a difference in composition as one was made from wrought and bloom that I had melted, and remelted the melt product again to further refine and improve the slag removal. The other billet was clean modern steel melt material. I had suspected P levels being the difference maker, but am interested it peer at the structures with the scope soon. Also, I dont talk about it much here, but I am a collector and user of japanese natural stones for my sanmai kitchen knives I make, and I have all of the sword related polishing stones and a lot of fingerstones for sword polishing (not pictured). So traditional stone polish with Hadori. The blade is a test blade. A tanto in size but no kissaki and was more of a shobu-zikiro in a way. I used traditional rice straw ash and ball clay mud slurry Nugui There were a few flaws on this end of the billet.
  16. Phosphorous also adds a contrasting element to the mix. It will visually contrast with the lower P iron. Edit: oops Allen beat me to it
  17. That kitchen knife with 9 fold oroshigane I kept and finally used recently. The patina revealed some fun stuff. The stone polish that followed revealed it even more. Bands of spheroidized cementite, quite large in fact. I need to peer down the scope to see what's going on, but it most certainly is cementite from here.
  18. Ran into some frustration because I felt like I was not seeing enough cementite spheroidizing. I figured I would see more for 1.3-1.4%. I nearly gave up on this bar. Them I forged it some more and gave it literally one last etch before chucking it to the side.
  19. It's probably cementite bands. Which is weird because they usually dont start showing up until forging.
  20. Ok, some updates here. I recently built a new, more durable melting furnace able to withstand 3300F using 94% alumina castable.This new furnace I am using a 1.5" blown propane burner I made for it. The first puck made in the furnace didnt turn out the way I had hoped, so I remelted it again with some more, higher carbon material (my oroshigane). This bumped it up to the 1.3-1.4% C range. I have been making 1.6-2.5% C crucible steel in the past, so this lower carbon content was a little new to me. I also purchased an electric kiln to do an initial roast of the puck. Now I have roasted the puck for 22 hours and am ready to forge this evening. What is most peculiar is without even forging, there are latitudal lines already bunched up it appears seperate from the grain boundary cementite. These last photos are 40x10 mag, dirty belt finish, longer than normal etch in 3% nital.
  21. He mentioned the test end was 5x5 microns with a 1g charge. The left side was a pearlite and ferrite strike with the indention being 15% larger and the centered hits are smaller, being cementite or iron carbide.
  22. It was really bizarre to see and try to decipher. Skip messaged me and said ledeburite, and my hunt for knowledge took off. I delved into my microscopy book and many items online. Found a lot of good information, and even stumbled across a bit of research that connected me with an archaeologist in Europe who happened to have already been following my work on IG, lol. Thanks Jerrod, I meant to make that clear.
  23. You are welcome Jerrod. I knew I was pushing into crazy territory, but didnt fully understand cast characteristics until most recently, and what to look for in my product. As stated earlier in this or my crucible thread, I had various samples of my crucible steel and some hearth steel for a researcher to look at. On of the samples was a 4fold piece of hearth steel. He had mentioned then that I had a clean band of heavy cementite, or iron carbide in the piece. At the time it was a mystery, but now things are getting so clear. This is why I love metallurgy and steel creation. Theres so much I learn the further I go in my journey that I am able to critically inspect previous work and findings a refine my understanding. Anyway, the piece was cool and he did take a micrograph, albeit not as bright as mine are. He also used a Vickers hardness test that the microscope was outfitted with to determine between ferrite and cementite structures. Inside that dark band it was showing all of or most of the white to be cementite at the grain boundaries.
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