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Klaas remmen

Georgian 'Bulat' technology by Zaqro Nonikashvili

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Thanks Greg and Jeff. If I understend correctly Greg, The elongnated pearlite can split up in globular cementite and ferrite grains? But the cementite balls would have to dissolve again and settle in line (at segregated impurity's as Verhoeven discribes)?

 

I got some new pics from Zaqro's work which I would like to share with you. This is an example of the 'Konasamudram' process. Usualy gives relatively big hockey-puck shaped ingots, which, according to Zaqro, were flattened further, and then cut into a spiral and stretched out.

 

The ingot was 480g, the finished Yataghan weighs 260 grams.

The pattern is nice but not clearly to see on this pics. I am waiting for better pictures.

Enjoy!

 

 

Klaas,

Please pass on a thank you to Zaqro for forwarding those pictures and comments....very thought provoking. That is the most beautiful dendritic structure I have seen. I will have to go and look at the files to see what that furnace looks like..I am not sure if I ever really understood how it worked ( I will try again).

 

Jan

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Christopher, I heard from Gotscha that he uses a lazer to cut his spiral B) But still, should be possible to cut with a shizzle, as they must have done in the past.

 

Jan, can you tell me why that is the most beautiful dendritic structure you have ever seen?

 

He told me when he was in Belgium that he fills this crucible with pieves of carbonsteel and charcoal, if I am not mistaken..

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And another picture of Zaqro's work. this has some alloying elements, it's the bar from which the microphoto's I posted earlier were made.

 

barZaqrohalf4scherp.jpg

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I meant to spiral-cut one. Unless you're suggesting a short cut, then forge out the tab, the short cut again, then forge straight...

 

I was thinking to bandsaw it cinnabon style.

 

:D Sorry, I thought you were talking about straight cut on the side of an ingot.

For the spiral cut chisel works. I did it ones, in one hand. It is ROYAL PITA. For the next time I will probably send it to waterjet. Expensive, but should work. They claim they can cut through up to 3" thick steel. Unless the jet will be deflected on carbides :lol:;) oops it may cut something near by :huh:

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Christopher, I heard from Gotscha that he uses a lazer to cut his spiral B) But still, should be possible to cut with a shizzle, as they must have done in the past.

 

Jan, can you tell me why that is the most beautiful dendritic structure you have ever seen?

 

He told me when he was in Belgium that he fills this crucible with pieves of carbonsteel and charcoal, if I am not mistaken..

 

Klaas,

The reason is that the photograph shows the beauty of patterns of cementite contrasted with pearlite...this is the type of photograph we want of the wootz blades. The ingot is difficult for me to see clearly ( I am using a magnifier while looking at the screen). There is a nice balance of cementite to pearlite and a strong pattern. The photograph is providing more than just information.

 

Regarding structures and beauty...my favorite structure (to see prior to forging) is one where you see two parallel dendrite stalks, arm branching between the two, and the dendrite tips of a third one in the middle.

 

Jan

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Does it look similar to that?

post-25420-1217712001.jpg

 

Dmitry,

That structure was probably in that ingot prior to forging..once the dendrite stalks are deformed it is hard to tell. The area just above the largest white bubble looks close to it. As the ingot cools some of the cementite seems to be migrating to grain boundaries...but some very similar shapes may be dendrite tips. I am just beginning to differentiate between the two ( attempting to). Next time I get a good ingot etch i will post it.

Jan

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Gotscha and his friend ware also in Gembloux for our 12th. BKS Cutlery Days, on November 13 and 14th.

Gotscha is also making very nice armours..

 

I appreciate very much that Zaqro and Gotscha showed us openly about this Bulat/Wootz making process, as well as the way they did this. Just to inform you about who this Georgian people are and how they look like (no beards) i herewith submit some Photgraphs. For those among us who are interested in some more information about the Bulat/Wootz session in Antwerp (Dutch language)or the work of Gotscha, this is the link to the website of Gotscha Lagidse: http://www.gotscha.nl/.

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Needles of cementite in the ingot I made on the solstice, this ingot has not behaved well under the hammer!

looks cool though :rolleyes:

FeC needlea.jpg

FeC-013a.jpg

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No, there is nothing but cementite & pearlite (and a couple sanding scratches) in those shots. Since I'm using a regular 'scope the cementite looks dark instead of light. This is the as-solidified structure, no heat treatments or forging.

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What etch did you use?

If you used Nital, your carbides should be white unless you use a darkfield microscope, no?

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I used nitric, which etches similar to nital. The carbides are indeed white to the naked eye, they just look dark because through the ‘regular’ (not reflected light) microscope they are reflecting the dark surface of the objective. I should have inverted the image so it looks more normal…

FeC inv2.jpg

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I used nitric, which etches similar to nital. The carbides are indeed white to the naked eye, they just look dark because through the ‘regular’ (not reflected light) microscope they are reflecting the dark surface of the objective. I should have inverted the image so it looks more normal…

FeC inv2.jpg

 

Jeff,

Thanks for he images. I see these "needles" frequently even with a hand held microscope.... The wavy line from center to about 2:30 is interesting as well..would be nice to know what is going on there. Your use of "objective" and "regular" microscope vs."reflecting" microscope is a little confusing to me. I look at metal through regular microscopes (which normally are illuminated from below) by illuminating with some light source from above...depending on differences in reflection to show the details. ? How did you change the image from dark to light ?

 

Jan

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Hey Jan!

I first noticed those needles with a 10x loupe, indeed they are not shy. They look like they would contribute a lot of potential fracture planes to complicate forging, this might be an ingot that needs to be baked to be forgeable. ^_^

By “objective” I meant the lens at the business end of the microscope, near the sample. Yes, when viewing opaque materials with a regular ‘scope one uses reflected light, obliquely from an external source. The standard metallurgical microscope sends the light down the tube and through the objective lens to be reflected by the sample back to your eye, that direct illumination is what my ‘scope is missing, and why them carbides are dark, even though I’m using reflected light to see them. The dark surface of the lens has a similar effect to placing a black background above a blade when photographing it so the blade looks dark. B)

Some image processing software lets you flip black and white values in an image, in this case it was Photoshop’s ‘invert’ button in the image adjustment menu. Since the pearlite is grey, it didn’t change much, but the black cementite becomes a more realistic white.

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Hi all

 

I tried the 'Georgian' technique again today, this time in a clay-graphite crucible that has been used for already 5 times.

the melt itself took 55 minutes, and the result was a sound +- 400g ingot with a nice spark.

I roasted it the way Zaqro did it, and forged it out to a bar +- 100mmX27mmX17mm in 45 cycles.

The pattern is rather fine and dendritic, but I hope to get a less dendritic and coarser pattern in further forging.

 

2011.jpg

 

So on this magnification, the two dark corners are +-27 mm apart.

 

Cheers!

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This is what I got out of it. Its pattern is still not coarse, but it's less dendritical. I managed to get one part of the bar to crack, I forged the oher part more carefully and it stayed togheter, but I got the upper side of the ingot to be the cutting side of the knife... typical, this one is kept as a reference.

Mes3totaal.jpg

close up:

zoonpatroonmes3.jpg

 

This is another melt I did, using Zaqro's technique. since the ingot was rather small and flat, I decided to try the donut technique... But I think I might have been to fast with the opening up, since it broke immediatly. I want to try it again with another ingot, more carefully.

The punching of the hole went suprisingly fast, just 7 heat cycles and a lot of cursing because I did not prepare for the punching well. The ingot was about 20mm high.

 

I think the donut technique is a logical way of processing the 'puck shaped' wootz ingots... plus I think it might have a big effect on the pattern as well. But again it seems that I need some more practice.

Donuttech.jpg

 

And finally there are two more quite nice looking ingots to be forged, one is about 400grams, the other 650. This last has got to be the nicest I have made, and I hope it did not take to much carbon out of the graphite crucible (this was the first time it was used).

Ingot5.jpg

Ingot5-1.jpg

Ingot6onderkant.jpg

 

Cheers!

Edited by Klaas remmen

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Cheers!

 

Klaas.

Yesterday, I melted some wootz like Zaqro does it, in coke ( only the heating process is the same the ingredient are not) . It was a little problematic, as I have no way of removing he ash under the crucible.... after about 1 hour I suspect I am getting a very oxidizing fire...cooling was fast due to me leaving the air intake open. Actually I am happy just to have the whole thing survive. The ingot is rough looking and it seems solid. Here are some pictures of the process. I hope to get my forge running today and begin forging out some older samples.

I am slowly increasing the ingot size to 1500 grams ( enough for a sword....I do not need a sword but would like to see if I can create a bar with a good pattern all along its length )..this one is 1075 grams and should have been 1150. There are about 30 grams of iron I cannot account for (Magic).

Jan

attachment=30281:cokefire.JPG]

 

 

 

 

 

 

[

Edited by Jan Ysselstein

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Hi Jan

 

nice success !!! ... i could never get an ingot to melt in coal/coke fire...it always ate a hole in the crucible and i'd end up with a big messy/fail. I'm glad it worked out for you...

-the ingot has nice pattern.. it should be a good one

 

i can't wait to see the snow disappear around here... so i can get back to making steel ... its too much temptation

 

Greg

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Hi Jan

 

nice success !!! ... i could never get an ingot to melt in coal/coke fire...it always ate a hole in the crucible and i'd end up with a big messy/fail. I'm glad it worked out for you...

-the ingot has nice pattern.. it should be a good one

 

i can't wait to see the snow disappear around here... so i can get back to making steel ... its too much temptation

 

Greg

 

Greg,

The pattern is very fine at the surface but very clear. I had a difficult time grinding this thing and worry the interior may not be the same as the outside.. had to quit due to the fire getting cooler and I do not think it has come to equilibrium. In terms of getting a better overall understanding of what makes wootz tick, this ingot has a place on my map. Just got over a big frost here ( by California standards ) and some snow...I put some of my precious charcoal under a few lemon trees to keep them from freezing. Actually that works quite well using the fines....it is like burning sawdust in a cold smokehouse..it just keeps smoldering.

Jan

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Hi Jan, That ingot looks good!! what kind of crucible did you use? a home made one?

 

I forged the last posted ingot into a bar using the donut technique, as Zaqro advised me.

 

It took about 6 hours with 3 people and a sledgehammer to get this little 300g ingot to a bar, and when I opened it a piece broke off.

 

here are some pics;

 

the ingot:

Ingot5.jpg

 

the hole, it took 5 punches, the one on the pic is a HSS punch!

gatponsen.jpg

 

a hole!

gerokken1.jpg

 

gerokken2.jpg

 

gerokken3.jpg

 

donutgesneden.jpg

 

openzetten1.jpg

 

openzetten2.jpg

 

openzetten3.jpg

 

The result is not great, a bit dendritic, I'll take a decent pic from the pattern and post it later.

 

Jan, let us know how the ingot handles please!

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Hi Jan, That ingot looks good!! what kind of crucible did you use? a home made one?

The result is not great, a bit dendritic, I'll take a decent pic from the pattern and post it later.

Jan, let us know how the ingot handles please!

 

Klaas,

Nice work and lots of it ...I am impressed you took it on I am looking forward to seeing the pattern.....

 

Thanks, this ingot scares me ( many should have but did not ). The crucible was home made, but to move things along ( the previous ingot took a long tome to remove from my tuyere ) I will be using a bought one.

Until Niko rescued his ingot I had never heard of that method ...stretching that particular metal with tapered punches ( sucking heat from the contact surface ) would not work on some of the ingots I have forged ( those having a bit of Phosphorous? ). As these ingots get larger I will flatten a bit and forge sideways as usual or flatten to 18mm and cut a coil or rings from the disc...then decide by looking at the pattern on the 18mm square bar how I want to continue.

 

Made some iron yesterday, as looking at 1500 gram melts is taking stock down quickly ( especially with a 50% broken crucible loss)....

 

Jan

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here are some pics of the pattern. What strikes me is that the outside, which was deformed by hitting with the hammer is much nicer than what used to be the inside of the ring (and which was deformed by chizzles and the anvilhorn)

 

the ugly side:

slechtekantdonut.jpg

and closeup:

detailslecht.jpg

 

the better side:

Goeiekantdonut.jpg

and closeup:

detailgoed.jpg

 

oh yes Jan, look for your loss of iron in the glass covering the ingot or your crucible wall. Also I always find some stuck to pieces of charcoal leftover in the crucible.

Edited by Klaas remmen

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here are some pics of the pattern. What strikes me is that the outside, which was deformed by hitting with the hammer is much nicer than what used to be the inside of the ring (and which was deformed by chizzles and the anvilhorn)

 

oh yes Jan, look for your loss of iron in the glass covering the ingot or your crucible wall. Also I always find some stuck to pieces of charcoal leftover in the crucible.

 

Klaas,

That bottom picture is of a very nice pattern...nice to make those little discoveries about the results of forging is it not. Yes the iron is in the slag which was suspended about 1 cm above the ingot.....the slag was again magnetic. I am off to buy a crucible today to speed up the process a bit. This will be a SiC crucible which I will compare to my graphite crucible in terms of Si pickup by the metal..

Jan

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