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Showing content with the highest reputation on 05/20/2021 in all areas

  1. Howdy.. Well it has been an interesting last bit...took a bit of maneuvering , wheeling/dealing and being creative to stay afloat with minimal (if any) studio time but now that things have turned around and orders are once again coming in..I am BACK!! I did get some serious writing done on book IV as well as figure out how to get a bigger chuck of that wavy feather pattern I have been worklng on..here is the reult of one blade for the cover photo of book IV.. I am keeping this one for myself. 31" blade, double fullers, file worked spine..(wore out 3 files doing it..this steel is tough on files..that or the quality of files has taken a nose dive....) welded from 1095/meteoric iron mix and 1070..great contrast.. I am calling it the "Quetzalcoatl" pattern... hilted with steel fittings and copal grip panels...Using copal was a very unique adventure I will say that... boy that stuff had to get HOT to melt..smelled great though... All in all turned out OK if you ask me.. So..... I'M BACK!! JPH (now the real work starts..getting back into the swing as they say..)
    5 points
  2. Pots are serious business, and I don't even like clay ;-)
    3 points
  3. Matthew, from what we can tell at sites that produced crucible steel in the old days, the old crucibles were mostly one-shot deals. If they lasted long enough to produce a single good puck that was enough, then they were crushed and used again. I suspect a lot of the very early development (WAY pre-iron age) of metal casting was luck, in the same way as when the Navaho started casting silver in the 1700s they discovered that old pottery shards from one abandoned pueblo in Canyon de Chelly made decent, if small, crucibles. Not that the wootz producers were using old potsherds necessarily, but the history of technical ceramics in the old world is quite impressive. Starting in the chalcolithic age and going into the bronze age, a technical elite figured out what worked over hundreds of years, and they did not share their secrets outside their guilds or tribes. Archaeologists still don't know how they made some of their crucibles, and bronze isn't nearly as hard on things as iron, much less steel. Just because they didn't use the modern terminology doesn't mean they didn't know exactly what they were doing.
    2 points
  4. Mac. That is a tremendous amount of work and information you have given to a person you have never met.Thank you very much.
    2 points
  5. That is excellent information, sir. Thank you for sharing that hard-earned knowledge. It is much appreciated.
    2 points
  6. Giving you a simple recipe isn't that easy. I was not making wootz but was trying to make large, first stage direct reduction pots, similar to the process described by Needham as in use in Shanxia, China in the 19th century. First, I talked with potters. After numerous clay trials I gave up on potters as being particularly useless and began reading patents. I followed them back through 'patents reference by' until I arrived at formulas I understood. Then I moved forward in the patent search trying out new formulas and recipes. Once I had a reasonable handle on the technology. I was able to talk with Ceramic Enginners without them putting the phone down on me in disgust. They really are very, very knowledgeable people who don't suffer fools gladly. The phrase, 'You're not even wrong' is a fond memory. As you can see but the pictures of my trial notes, I tried all sorts of patents and variants. Outside of very sophisticated ingredients and manufacturing methods I found four, basic starting points. Tradtional clay graphites, like Berlin pots. Prof. Vasily's bulat pot recipes amd my variants My own shrinkage adjusted, clay graphite pots. And, a TiO2/ clay, silicon-carbide recipe I based on a patent for 'Self healing' crucibles. I tried a lot of different things. I tried powdered aluminium addition to create 'Exothermic, internal drying' of clay bodies. I tried borax addition to create 'self glazing' pots and colloidal silica additions to prevent graphite oxidation ( OK for low temps but at steel ranges the whole pot just went into solution ). Almost all of the carbon/clay pots will work for standard uses. Flake graphite is what you need and that posed my biggest problem, because of where I am. I was forced to use graphite furnace charge , made from ground electric furnace eletrodes or substitute with graphetised coke. Those I made with good grade graphite flake worked fine but were uneconomical to make. Shrinkage reduction pots. I won't go into detail here but clays shrink when they are fired. They shrink at known rates. Kyanite expands as it converts to mullite. It converts at the same temperatures as clay contracts. Hence, you can add kyanite in amounts to ballance this shrinkage making your pots ( in theory) more easier to fire and less susceptible to thermal shock Standard 'Berlin' crucible recipe fire clay 40% Graphite 20% Powdered coke 25% Grog 15% ( traditonally ground broken crucibles) I took these % by weight A 9kg bre would be 3600gm Fire clay, 1800 gm graphite, 2250 gm powdered coke, 1350 gm #200 grog. My shrinkage adjusted Berlin Fire or 'Ball' clay 22% Kyanite 42% Grog 20% Graphite 16% Prfessor Vasily's bulat pot recipe follows a 7.3,1 ( or 2) ratio 7 parts volume Flint clay ( I used chamotte or 'flint grog. This isn't a clay but a hard, fired material) 3 part fire clay 1-2 parts grahite. This is quite a tricky brew to mold as my chamotte was a a bit coarse. It would probably do well in a rammed mold. If you could find a finer chamotte, this recipe would be worth a second look for small, round wootz pots. I made a variant that was shrinkage adjusted and used a finer, flint grog. It was much finer in texture and really quite tough for 'one off' use. firedc clay 25% Graphite 6% Kyanite 47.5% Mulite 9.5% #200 flint grog 15% A brew that was quite promising in A8 size, rammed pots. This has a TiO2 addition to create a 'self repairing' crucible as per the patent. A similar patent included 5% metallic aluminium powder. Once made into a wet clay, the water/aluminium reaction is claimed to dry the pots from the inside and result in Al2O3 additions. I made about 9 variants of this and had to pack up my whole shop and move it before all the trials were done. I did several recipes with alumina additions, but both the alumina and the metallic aluminium didn't seem to make any positive difference to this basic TiO2 recipe. For the test pot , I replaced graphite with graphitized coke, simply because I couldn't afford more graphite. It handled a 2kg cast iron melt but did show scouring at the slag zone. It was also very thermally transparent ( probably because of a porous structure caused by the coke loss) and the iron melted in a record time for my setup. I would definitely try this one again with flake graphite in a rammed mold. Fire Clay /ball clay 35% Graphite/G coke 45% silican Carbude #200 17% TiO2 3% Glazes I tried a lot of different 'washes' to try to prevent carbon loss during bisque firing. One turned out fine for high temp pots. Sil. Carbide powder (fine) 164 gm Kaolin 36 gm TiO2 20 gm Al2O3 20 gm Silica flour 20 gm Water to form slurry. Painted on bisque fired pots, dried and furnace fired under use to stoneware + temps. I did some with a anhydrous borax addition and these produced the nice, chocolate colour you fine on commercial Borosilicate i.e. clay graphite pots. Fine for non ferous but degraded badly at steel temps. A simple borax glaze brew I developed for non ferrous pots, 2 heaped teasoons of Kaolin 1 teasoon anhydrous borax powder 4-5 teasoons silicon carbide powder ( 1200#) I did make several non-graphite pots which worked well at low temps but grapite is the main 'ant-wetting' agent in clay pots that stops slag errosion at iron and steel temperatures. I'll post a few picture of my notes so you can get some idea of the volume of trials I did between 2004 and 2008. In the end, I decided to bypass crucible refining and allotted to make a small, tilting open hearth furnace for the Basic process. These note are only a fraction of those made over the four years. It might be a quick read but it cost me a lot in time and resources when just putting food on the table was a struggle.
    2 points
  7. Back to the tsuba. It took me a while to decide on the actual design for the reverse side. I knew I wanted 1) a mirror image of the moon, waxing instead of waning, and 2) a young bamboo to contrast with the mature bamboo on the obverse. This is to tie this katana to her sister blade, a wakizashi I made last year that featured a young and a mature bamboo on the sides of its habaki. I worked on the mirror moon and clouds while still mulling over the young bamboo design: My issue was that a young bamboo meant thin shoots and slender leaves, which would have been quite difficult to pull off as an inlay. I considered thin wire inlay, but the leaves were going to need to taper very thin, and I didn't think I would be able to sufficiently undercut the channels (not to mention the wire would have needed to taper as well since the background shibuichi is somewhat soft and wouldn't allow 'smooshing' the wire in). I could think of two options: 1) 'nunome zogan', similar to damascening, in which I had zero experience, or 2) katakiri, or single chisel cuts carving. I had a pre-existing interest in the latter, some limited practice, and a scary experience with the fuchi. So that's what I chose I started with quite a bit of practice, to hopefully hone the strokes I'd need and also have some fun with on-the-fly composition. Here's a short video of one session (my self-critique here: strokes are not great but okay, composition is way too busy). Ultimately I felt that the reverse side should also be quite a bit more muted than the obverse. When it came time to settle on a design, I chose to keep it very simple, and just aim for clean cuts and good balance. I really did not want to ruin weeks of work, so I practiced the design about a dozen times on copper before I was in "the zone" and felt the impulse to go for it. This is 19 chisel strokes later: And here's the whole reverse side, complete and mounted: I know it doesn't look like much compared to the other side, but in a way, I am prouder of this side. For the other, I was able to make and fix several mistakes, but there would have been no good way to fix one here. I am growing very fond of katakiri, it almost feels like sumi-e painting. Next, patination.
    2 points
  8. I think I've asked this before, but I'm having some trouble figuring out where to put the pivot hole in a folding knife blade. Is there a rule or some sort of tutorial around? Geoff
    1 point
  9. Here is another tool making video you might enjoy:
    1 point
  10. Mr. Schneider, I have shown you the little I know. I have given my opinion of the use of modern coatings on crucibles. I'm sure you will develop your own recipes from research and experiments. I am a tradesman, not a teacher. Good luck with your endeavors.
    1 point
  11. Just a couple of broad strokes. In high temp wares, clay is often your enemy. Yes. I know, it sounds stupid, but if you think of clay as a 'green strength' binder that holds together the more durable materials until they solidify at higher temperatures, you're getting my point. Try to keep the clay content as low as practicable. All they clays I used , whether Fire Clay , ball clay or Kaolin are all high Alumina clays. In some trials I tried high iron, terracotta type clays. In low %'s , some made reasonable non-ferrous pots but most just melted at stoneware temps. And as for historic practioners. It's very difficult to remove people from their materials environment and understand how they did things. Until recently, many of the 'unlikely' ingredients in old recipes were brushed off as 'magic' or 'myth'. Modern analysis has made their purpose known. An example would be straw ash. Straw ash is used in Japanese Tanren forging and in many old crucible recipes. In Europe, silver sand was used as a flux for wrought iron, but not for steel. The liquid/solid phase for steel is simply too low for coarse silica to melt. However, the silica in Straw stalks is in the 8-12 um range and will act as a flux at much lower temperatures than sand. So, the prevalent idea for many years in the West, that the Japanese used straw ash predominantly as a carbon source have been proven wrong. Likewise , straw ash ( colloidal silica in the 8-12 um range) in pots is now embraced by numerous high tech patents for carboniferous refractories as it has been found to coat graphite and prevent early oxidation. Another example would be a Japanese iron patination solution that contained frankincense. Seems a bit bizarre but does make for a nice smell. Until, you talk with a biochemist working at an essential oils lab and she inform you that Frankincense under heat breaks down to a hexane component that would act as a de-greaser. The history of archaeo-metallurgy is replete with mysteries compounded by assumptions about our predecessor skills and knowledge, or the lack thereof. FYI Graphetised coke is a fine carbon make from petroleum products. It is identical to the coke build up you get on oil burning furnace injectors through incomplete combustion. It is far less dense than flake graphite , with an open , porous structure. It tend to burn out of pots before the body has sealed at high temp , therefore leaving a less slag resistant surface but an open fabric with much higher thermal conductivity. Very similar to the purpose of charcoal in Japanese blade clay. My hypothesis is that controlling thermal conductivity is why both flake graphite and coke dust are found in the 'Berlin' crucible formula.
    1 point
  12. bastards; all of them.
    1 point
  13. OK it is a go I have to gather some copper and just found a #6 crucible ( Graphite )..I will post the result. Lost wax . Jan
    1 point
  14. Short update of this project. I needed more bloomery iron so I had to prepare an iron bloom I smelted some time ago. A few weeks ago there was an opportunity to use a historic water-powered hammer in GdaƄsk in Poland. The forge exists in this place since 1597. It was really great experience to use 250 kg dies. The 12 kg iron bloom has been flattened really fast. After heating and forging more than 6 kg of iron left. Below I link the video of this process.
    1 point
  15. Well... failure is always an option. Had a failed forge weld in my feather pattern. For only my second attempt at damascus, ill take it. Got my shed a little warm, 2" pvc pipe was across my lofts on both ends. Smh.
    0 points
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