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Jokke

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  1. take a look, this needs a fast internet, so people take care: http://www.didihammer.de/3d/eingang.html maybe now you can understand why I love to spend some time with my friends there and with all the hammers sorry I did not take pics from the two small blades yet, but I promise to do this soon best regards
  2. Jokke

    Forging a sax

    I'll just help Dietmar out a bit - he will not mind that's the place I worked with him lately, you can all imagine that I love to spent some of my spare time there! Owen: it is very near to a town called "Lüdenscheid" and the "Bremecker Hammer" belongs to the Lüdenscheid museums if you are on the autobahn (A45) you must exit on "Lüdenscheid Süd (- South)", up the hill a bit into the roundabout and then to the right, there are good signs to follow the museum is closed mostly over wintertime, though Don: nice headstone and avatar!
  3. yep, that's how he does it glad to see you here Didi!
  4. the chrome ingot turned out to be a pain in the a.... could forge one half out a little, then it got too hot and crumbled like cottagecheese, a quarter of it but I was talking to some visitor, my own fault but then I was able to forge out the last piece of my old "normal" wootz and it turned out to be a nice little blade with a fine lining-structure and I forged a blade out of a wild "damascus" piece from a friend, with some nickelsteel in it - I will put in some pics later this week, I called them truth and copy it was a fine weekend - and I was able to impress some kids with what can be done with iron and steel and the museum got some extra money from donations - so everything is fine just one week of normal work and then I will be into renovations so I will be out of here for a while I'll try to come back with some traditional Wootz then is anybody coming to Belgium in November then? best regards
  5. Hi Greg, you are right about Niobium (Nb) having a good effect on the carbides, making them very fine in comparison to Vanadiumcarbides - Achim did use Niobium and wrote about it in the german forum it is the Cb (columbium) in the chart, which is not used as its name internationally anymore in chemics Juha must be Prof. Perttula, whom I have not met in Finland - but I had some talks with Mr. Roselli, nice guy, but does not talk much about his production ways casting Wootz into sand, well it can be done, but I have not seen very nice bandings in the blades I had in hand, they looked more like a dendritic bulat to me you do have a point on the mentioned oxides, at least some of the fails I had with holes and so I think came from oxides and gasses forming from those at the end of the melt and I hope I did not run down the temps too fast then great: when I think about that the melting of the ingot is just 10% of the way (as Achim has put it) I cannot wait for the forging tomorrow I have to ride about three hours to get to my friends and that is worth every minute of it
  6. Oh, yes, in the sense that highalloy material needs a lower temp to melt, but it does "eat" on the clay-g-crucible inside walls a lot more than traditional wootz I used 1.2436 (X210CrW12) in my last smelt which is an AISI D6 2,1 C 12,0 Cr 0,8W (Tungsten) tried to get it to 1,8%C and more Chrome (13-15%) by using another high alloy steel and it did melt very good and produced big dendrites - I hope to see more about those when forging it to stripes I will take a piece of the 1.2436 and forge it out as well to see how that looks like (it is ledeburitic and hardens to 64 -65 HR-c, so after annealing it can be around 60-62 HR-c) in comparison
  7. Jan, Koraat (Ulrik)started with Wootz, he had learned from Achim, too, as far as I know, but he switched to smelting his own steels and pouring them as a cast-steel into a form. He describes what he does here, in German (he lives in Austria, though): http://www.koraat-knives.at/public_html/menu3submenu1.php he mainly does five different steels: http://www.koraat-knives.at/public_html/menu3submenu2.php He melts in a coke-fire, with a system where he lets the air blow in from below, a kind of tube with a mesh of steel upon which is laid some coarse stones, above them the cokes in which he puts teh ingot to smelt his steel but I did not have a more personal contact with him, so I only know from reading - he is rather young, a learned goldsmith and he finished the goldsmithacademy in Vienna, too, before becoming a knifemaker. well about chrome-ingots, I guess it is more about the modernised form of rust-resistance material and actually being able to do it, besides that it seems to be melted easierly in my smelter than the real stuff and I was able to get more people interested into crucible steel in this way - and more support for free from bigger firms (this Hobby is not only time-consuming ) a pure high-C steel (UHC) is harder to get than any fancy highalloy stuff, besides Achims "C145 Super Clean" Klaas, I might be able to do some forging with heavy hammers this weekend, in an old forge that is now a museum: http://www.bremecker-hammer.de/start.html take a look at the bottom of page and click on VR Rundgang from outside look at this: http://www.didihammer.de/test.htm my friend, his wife and his gang is taking care of the whole thing, really cool and nearly the only opportunity for me to work with heavy machinery and not having to bang bang bang with my hand-hammers
  8. Hallo Jaques, pls send some more information about the meating with Achim in Gembloux - I would like to attend very much and think I can make it this year, so add me to the list, if you do not mind a special Wootz-Symposium, WOW and on this side of the globe... now that is something for my heart, Boys... Jan, I am sorry, but I do not have any special link from Achim on traditional Wootz, but I can assure you that he is more into the traditional stuff (and he is very clear on that, too) than into chrome he was the one who introduced me to the work of Ann Feuerbach best regards
  9. No no, the brick was there to put the hot crucible on it after taking it out- I have tried different materials to put under the crucible, to lift it up for 1 or 2 cm inside the oven. The flame of my burner comes in directly above the bottom, so the biggest heat is about 2cm above the ground level. That is why I started to put some furnace material into the middle of the bore as a stand for the crucible. Lately I use the rest stuff from used clay-g-crucibles to lift the charge up about 3 cm - it would probably be better to have some stands out of Si-Oxide, maybe like a tripod, because that material gives faster and better transport to the heat of the flame - then there should be less cold areas to deal with - SiO2 melts at about 1700°C, so that should work as well as Aloxide melting at over 2000° I still have some small black rods of Al2-O3, but am not sure how their transport of energy is compared to si
  10. wrong side? for the flame it makes no differnce if it does go around from the left or the right side of the crucible but there might be another point that I did not make the walls of the oven straight - I thought it might be good for the flame to swirl better this way, maybe I do force it up too fast this way Achim wrote in that link from 2007 - I remember reading it years ago..: >>Hochfahren auf Schmelztemperatur dauert so etwa 45 Minuten. Dann halte ich für etwa 30 Minuten. Da dann alles flüssig ist, macht es keinen Sinn, länger zu halten. Dann fahre ich über etwa 90 bis 120 Minuten den Gasdruck von etwa 2 bar sukzessive auf 300 mbar zurück. Dann schalte ich ab und schließe den Ofen mit Keramikwatte (Brennereinlass) und Steinen (obere Öffnung). In aller Regel ist dann immer noch vieles flüssig im Tiegel. Nach etwa 1 1/2 Stunde kann man aufmachen. Aber gut heiß ist der Tiegel dann immer noch<< he heats it up for 45 min, holding for half an hour (2bar of gas injection)- he asumes that the ingot has melted by then, that is why he slowly drowned the gas from 2 bar to 300mbar within 90-120 min... funny that you give me just this threat to reread. He reduced the temps much slower than I remembered and saw lately, for example in Solingen in last and this year so going for three hours until reaching an end is not too long, then I can do maybe two melts with one bottle of propane
  11. no niin, you answer faster than I can write my thoughts, Niko I did measure the flame I guess, no touch system, laser pointed.. there is a point in that the smelt is becoming just liquid and I end the heating phase too soon... really looks like we will have to do some smelts together, maybe next year for that I will come up to the "north" of Finland, too but I do know that is not all the way up, where you live... rather easy to find, isn't it... my little furnace is "just" about 60kg... and not half that fast (with the venturi burner) I really enjoy this international exchange of thoughts and experience, guys thanks a lot!!! here is an old pic of my smelter
  12. Jan: you do have a point there that the ingot looks like it was hotter in the downer part Niko: what kind of insulative-cast do you use? I still have some blast-furnace repair stuff, it has to be mixed with some water and then it can be poured or smeered into the form, needs little time to harden and can be heated up nearly immediatly but does cost a little fortune, too, mostly because of transport 60mm sounds like a lot - and heavy, too
  13. hmm... Achim teased me by saying, he does one kg in an hour and I have seen his sytem a couple of times - and always thought "well, it looks like mine " or mine looks like his, but that seems to be from outside only energy absorbing, well, that is why I ordered some more high-temp insulation, kind of mineral-blankets that stand up to 1400°C, so they promise to be a bit more effective than the ones I have now (1200° cushings) the thought is that the walls of the furnace will reflect as much of infrared heat as possible and not to let the heat hrough the walls of the old 11kg propane-bottle that I use as a "frame" but it looks like this weekend not too much is going to happen any more we do have some rain and thunderstorms and so I rather stay inside and away from the veranda where I keep my "workspace" at the moment I hope that this will improve in the next three month, when we will move to the new house, after renovation, there is an extension to it just for me 4x8m and no direct neighbor
  14. I have not used ceramic crucibles, because I feared the mess in the smelter that would happen, when out of some reason the crucible gives up to hold the molten iron - so I started with clay-g ones and after readjusting the burner and the flare of it in the second smelter I started to get sound ingots, but I normally needed 3 hours for one melt and lots of propane this is why I wanted to optimize the process abit and ended up getting that holes-and -cranky stuff need more patience but at least the highalloy stuff seems to work
  15. here the pics from the cromewootz now cut in two nice to see the needles along the chromecarbides, too bad I only have a small looking glas to enlarge the pic a bit:
  16. Jan, that is an interesting text - I saved it for further reading so I understand you did put the material for adding C on the top of the smelt any special reason for that? and what did you use?
  17. Moikka, so it must be MnO2 then, must see for a source of it though as to the melt, yes, my laserpyrometer showed a clear 1600°C and then it went to ---- so at least in the flame there was enough heat, but the prob looks like not all of it went inside the crucible so I do have hope that this will be different with a si-crucible do not know when it will arrive here, though and I do not have any experience of how long it will last in my smelter the guy said that the walls are thicker and that there is also clay-graphit in it to make it stick together so today I am going to cut that ingot with the (hopefully) ~15% of chromium in it, so it should be a 1,5%C and all wanted it to a high alloy rust-resitant crucible steel Dmitri has wished me luck and strength in my arm to forge that stuff before, so maybe I will try me luck at about 950° forging temp... I'll see and let ya all know
  18. Jan, I think it will not be easy to pre-count the amount of C that will be in the next smelt like this, you say o,5% at the bottom and 5% hypereutectoid cast iron on top with graphitisations hmm.. I did not have this before always tried to keep away from castiron ranges
  19. Sorry Jeff, thx Jan for the pics hmm looks interesting... I just received the data from three of the incomplete melts I had made: here the ones from a second smelt from the material made from a Oolith (with about 26% of iron in it) smelt-reduction in a rennoven last year: C 1,27 % much more than I wanted it to be (it was supposed to become neatly forgeable steel 0.8 for a friend, because it is ore from his home-region) Si 0,39 Mn 0,01 P 0,242 !! that may explain some of the probs in the first smelt I did with that stuff S 0,282 !! I will have to see how I get rid of those as much as possible Cr 0,03 Ni 0,07 Mo 0,01 V 0,01 Co 0,02 Nb 0,003 Cu 0,02 a N of 1,132% was considered a fault because of the holes the first, bigger 1,6kg cake showed a C 0,826 % instead of the expected 1,8% C: so that explains the graphit powder that was in the caverns Si 0,23 Mn 0,06 P 0,015 S 0,016 Cr 0,08 W 0,00 Mo 0,01 V 0,02 Ni 0,05 Co 0,02 Nb 0,001 Ti 0,002 Cu 0,04 Al 0,001 N 0,020 just so hypereutectoid- and due to the incompleted melt so the second faulty-melt showed this: C 0,956 % at least a bit more and it was in the oven at high temps only 20 min longer Si 0,23 Mn 0,20 P 0,017 S 0,017 Cr 0,38 W 0,04 Mo 0,04 V 0,01 Ni 0,24 Co 0,01 Nb 0,001 Cu 0,10 N 0,014 at least now I know how to calculate the next smelts. I have had more contact with the guy at Mammut-Wetro and I may be lucky to get a Si-graphit crucible from him which is supposed to take in the heat much faster to the steel than clay-g crucibles, so it should be "easier" to get to the right temps and hold the charge there, too. As far as I understood the si-g is really expensive, but he might do me a favor and I will not be able to do those analysys' very often, they tend to be expensive, too... but I have learned more about the making of clay-g crucibles from that guy, when I get the new crucibles I will make a go on a new smelt and report if there is a difference in the quality I am still thinking that it had been the first times that I used graphit powder as a source of C for the smelt (Anossov used that too), but it did not get absorbed as easily as the flower-ground powder I had made from charcoal before another aspect to be checked...
  20. the ones from Ireland is over 4000 years old, that from Germany between 1 and 2000 years, long enough in the acids of the bog seems to make better quality
  21. Hi Jeff, looks pretty much the same as mine - the smelt with the pieces ot wagonwheel, which had lots of short red sparks when cutting it, my smaller ingot, the one with the real thin crucible wall around (Niko: you are right, I was lucky!) had a much better spark, long and bright with over 1% of C, and it got more dense than in the first melt - remember that was bloomery stuff - I am still waiting for analysys results. Niko: to me it looks very much like a crucible problem, although my friends in Germany do not believe so I ordered some new high-pressed crucibles (for 18 Euros the piece) from Mammut-Wetro, who have a bigger firm in the east of Germany - the Si-carbide ones are really hard to get and usually not as small as A5 or A6, but I might be lucky so I will be able to do a clear comparison soon (have ordered some insulation wool for >1450°C also from there, I have to rethink the inner size of the smelter, too
  22. well, I had hoped for better (at least the looks of them raised my feelings) and reaped the same as before, after cutting them apart I was more than disappointed but take a look for youselves, the smaller cake was 1,2, the bigger 1,6 kg
  23. here are some more pics f after the drying and after a short sanding to show the figures in the wood I like it -and will use some of it soon... on the first three pics I used some alkoholrub to show the lines better
  24. you can use it like normal wood, it should have been dried thoroughly though, if this is done, it will not crack. You should use something else as a gard and maybe another piece of hardwood or horn at the end, for boagoak can be quite soft (had some from Ireland that was very black, beautiful but rather soft), the one I have is very tough, like oak.. no need to stabilize it if it is dry and stabilized there will be another feel to it
  25. just finished two smelts in a row and I did change a few things on my system: first, I let the oven start up empty to give it a pre heat then I started the normal smelt, actually a remelt with some more C and some more of the steel from that old cart-wheel after it was above 1300°C I used an old vacuumcleaner as a blower and closed all other holes from the venturi with ducktape (jeesusteippi ) it was at 1600° after 15 minutes and I kept it there for over half an hour then I cooled the ingot rather fast and got it out the crucible had been on a little stand made of an old crucible, but the walls of the crucible that I used for the second time (clay-g) were so thin that they broke as I took out the ingot (no pics this evening) the second smelt with the presmelt material I still had from the rennfurnace of last year went into the crucible with glas on the bottom, to keep the steel high enough that it will not break the crucible walls when heating up. I added some more C to it, although I am still waiting fot the analysys of what is inside. But the smelt went up to 1600° in less than 20 minutes and I left it high for over 40 minutes, then changing the system back into venturi until the gasbottle was empty, which took about 20 minutes, so I am quite sure there was a rather slow cooling phase. it is still in the oven and I will open it tomorrow after work. So I had three smelts out of 11kg of propane, which seems ok to me, but two crucibles went in, too and I used the heat of the second smelt to give a little heat to the first ingot, but it did nor go over 1000°, so I will still have to do a diffusion heating to it hoping for better...
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