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Jokke
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Jokke.

 

One thing more..

 

In pic that shows your furnace, under the crucible is small brick...right?

Is that what you use under it in furnace bore douring run?

And how hi from bore is your burner hole in bore?

 

I have notised that IF burner hole is at bottom level and only shallow riser is used, heat is lower at bottom.

But if riser is rising crucible about hight of the burner hole off actual flame will not point to the crucibel , and heat it cycling around it.

So crucibels bottom is just pit above the burner hole in bore.

 

Niko

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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

Jokke

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wrong side? :D

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

 

Jokke,

Achim was instrumental in helping me understand wootz and the need for the diffusion process, yet I only associate him these days with Rust Free "wootz". Do you know of a link to some of his work with clean iron and carbon, closer to the wootz we associate with the historical blades being studied.

 

Jan

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Ja,

 

I know it's very far for you, but if you like to learn a lot from Achim about wootz of all kinds, you can come to our event "wootz affairs" in Gembloux, Belgium, on November 11, 12 and 13th. of this year!

Achim is the main organisator and is leading the symposium!

It happens during our BKS Cutlery Days.

A lot of other wootz specialists will be there too.

More information's soon.

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Ja,

 

I know it's very far for you, but if you like to learn a lot from Achim about wootz of all kinds, you can come to our event "wootz affairs" in Gembloux, Belgium, on November 11, 12 and 13th. of this year!

Achim is the main organisator and is leading the symposium!

It happens during our BKS Cutlery Days.

A lot of other wootz specialists will be there too.

More information's soon.

 

Jacques,

 

That would be a great trip, and if I could, I would be there, no doubt about it. As it is, I am scheduled to be there at a different time but should be able to get together with Klaas...I am working hard to get some really nice samples made so the vistit will be a good opportunity to meet in person and compare wootz samples and ideas ( I love that Belgian beer ). Once I was driving in Belgium and saw a road sign leading to a town with the same name as the beer I was drinking several times a day .....when we got there all I saw was a Nuclear Plant and I got the hell out of there. The museum recommendations Klaas made are also booked, all in all it will be a great learning experience....but I want to stand there in that museum with a special piece of metal in my pocket.

 

The experiment with the graphite I posted above, connects to the Georgian bulat making method. As liquid cast iron trickles through a layer of carbon ( in my experiment the carbon was touching the liquid cast iron at the top surface) , it picks up even more carbon...so one could have 5% carbon iron dripping into the space occupied by low carbon iron...blending into a homogeneous melt prior to crystallizing. Yesterday I made some crucibles ( not so porous) which may allow me to try the method in that long thread . I will have to run at lower temperatures so the damn things do not soften.

I do not have a sand around here which melts at 1100C ( actually a local sand quarry has given me some samples from their sand washing settling pond and it melts very quickly..maybe I will try it). I may try rice straw ash (m.p. 800C) and add a little silica to it to raise the melting point.

 

Jan

Edited by Jan Ysselstein
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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

Jokke

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Jacques,

 

That would be a great trip, and if I could, I would be there, no doubt about it. As it is, I am scheduled to be there at a different time but should be able to get together with Klaas...I am working hard to get some really nice samples made so the vistit will be a good opportunity to meet in person and compare wootz samples and ideas ( I love that Belgian beer ). Once I was driving in Belgium and saw a road sign leading to a town with the same name as the beer I was drinking several times a day .....when we got there all I saw was a Nuclear Plant and I got the hell out of there. The museum recommendations Klaas made are also booked, all in all it will be a great learning experience....but I want to stand there in that museum with a special piece of metal in my pocket.

 

The experiment with the graphite I posted above, connects to the Georgian bulat making method. As liquid cast iron trickles through a layer of carbon ( in my experiment the carbon was touching the liquid cast iron at the top surface) , it picks up even more carbon...so one could have 5% carbon iron dripping into the space occupied by low carbon iron...blending into a homogeneous melt prior to crystallizing. Yesterday I made some crucibles ( not so porous) which may allow me to try the method in that long thread . I will have to run at lower temperatures so the damn things do not soften.

I do not have a sand around here which melts at 1100C ( actually a local sand quarry has given me some samples from their sand washing settling pond and it melts very quickly..maybe I will try it). I may try rice straw ash (m.p. 800C) and add a little silica to it to raise the melting point.

 

Jan

 

 

Hi Jan

 

I wonder why you have left over graphite in a hole in the steel... I read that carburisation of iron or steel is only hapening when the metal is in contact with CO, and not when it is in contact with just C. Verhoeven describes it very clear in his book ' Verhoeven, J.D., Steel Metallurgy for the Non-Metallurgist. 2007, Ohio: ASM International.' I don't know what happens when your liquid steel is in contact with carbon, but I assume it pics it up rapidly, withoud the need for gasforming.

 

Maybe the easiest way to carburise the iron to make wootz is using charcoal, as that forms gasses when put in high temp? Just a brainfart...

 

If you do not have sand that melts at the good range, try normal sand from outside and heat it up with a flame... We use common white sand for forge welding, so that does the trick in the crucible as well! if you don't find anything, just use a thick layer of glasspieces, works great too!

 

Jooke; that chrome wootz looks.... hard! I am curious what is will become! As for your other smelts, the one with the dendritic 'tears' seems to have giant (thick) dendrites! I wonder what that effect would be on a pattern.... :D

Edited by Klaas remmen
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Hello Jan, Klaas and Jokke! :D

 

It comes a lot more informations about the symposium soon.

Achim will have more details about the peoples coming in Gembloux : he hopes to welcome Ann Feuerbach and a lot of others!

I hope also to see you together and it will be a lot of delicious Belgian beers and food ;)

And, of course, a lot of courses, demonstrations and workshops !

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Hi Jan

 

I wonder why you have left over graphite in a hole in the steel... I read that carburisation of iron or steel is only hapening when the metal is in contact with CO, and not when it is in contact with just C. Verhoeven describes it very clear in his book ' Verhoeven, J.D., Steel Metallurgy for the Non-Metallurgist. 2007, Ohio: ASM International.' I don't know what happens when your liquid steel is in contact with carbon, but I assume it pics it up rapidly, withoud the need for gasforming.

 

Maybe the easiest way to carburise the iron to make wootz is using charcoal, as that forms gasses when put in high temp? Just a brainfart...

 

If you do not have sand that melts at the good range, try normal sand from outside and heat it up with a flame... We use common white sand for forge welding, so that does the trick in the crucible as well! if you don't find anything, just use a thick layer of glasspieces, works great too!

 

Jooke; that chrome wootz looks.... hard! I am curious what is will become! As for your other smelts, the one with the dendritic 'tears' seems to have giant (thick) dendrites! I wonder what that effect would be on a pattern.... :D

 

Klaas,

I am not sure what the "hole" refers to but what I had was : a large crucible, remelting a cake which was originally made in a narrower crucible...plus a few bits of metal to make sure the carbon content was about right. There was no glass until just before shutdown ( that glass was puled out as it would not turn to liquid while sitting on top of a bed of charcoal)). On top of the melt was about 500 ml of chopped wood charcoal.

 

As Niko questioned the other day...the whole thing Was liquid and the liquid iron ( already well above 1.5% carbon ) absorbed carbon from the charcoal...this phenomenon is well established as happening in blast furnaces and in certain methods of upping the carbon content of a batch of steel. Every probe made with a steel poker indicated molten metal. Slowly cooled this very high carbon cast iron ( at the surface of the ingot) produced graphite.

 

What I would like to know and demonstrate for myself is..in a system where carbon and carbon monoxide and carbon dioxide exist at a very high temperature does carbon monoxide ( the prevalent gas) contribute to raising the carbon level in liquid metal...in that situation the liquid would only be in contact with the gas phase.

 

I have redone some of my cracked crucibles ( drying too quickly) and am ready to jump back to the Georgian post to attempt to duplicate what Adam has done..I never use nails and bought some to make sure I add no rust to the batch( very expensive steel) . Thanks for the sand tip, I will try pure silica ( ceramic store) and about 30% sodium carbonate , based on the diagram it should melt at about 1100 C..... ( I just hope it does not eat my crucible).

 

I don't know if I am the only one ever experiencing this but my little wootz pieces ( all cracky) waiting for pattern development are evolving and slightly changing over time.

 

Jokke,

Thank you, when I get that piece of metal I am looking for I will post it on the German Language forum and get some direct exchange going with Achim. If this event out there gets any bigger I may have to do two trips.

I am curious what the appeal of the high Cr,W is..is it the look, its uniqueness its cutting ability? There is a fellow out your way named Koraat..are you doing the same thing or is he after something different?

 

Jan

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Jan.

 

I still have to questioned this...

You said that ingot has 0,5 % up to 5% of C to to bottom, right?

I questioned that, it was not molten ...Yes You did not claimed it at first time I asked, but now you say it was molten.

So was it molten or not?

My point is that if you had 5% C it will be molten much lower temp than 0,5%C and all this in crucible will be mix up as one IF given temp and time right and there cant be C differens like that in fully molten liquid charge..I think.

 

Or are you saying that douring cooling down bottom of ingot freeze about 5% C and some how top section turned out 0,5 % and all that free graphite that some how nuglated douring slow coolign in top too lowering the steels C to point 0,5 % + that graphite.

 

Niko

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Jan.

 

I still have to questioned this...

You said that ingot has 0,5 % up to 5% of C to to bottom, right?

I questioned that, it was not molten ...Yes You did not claimed it at first time I asked, but now you say it was molten.

So was it molten or not?

My point is that if you had 5% C it will be molten much lower temp than 0,5%C and all this in crucible will be mix up as one IF given temp and time right and there cant be C differens like that in fully molten liquid charge..I think.

 

Or are you saying that douring cooling down bottom of ingot freeze about 5% C and some how top section turned out 0,5 % and all that free graphite that some how nuglated douring slow coolign in top too lowering the steels C to point 0,5 % + that graphite.

 

Niko

 

Niko,

When I probed the liquid I touched bottom many times..was this the crucible or a layer of decarb........,I do not know but it is quite easy to test to see if the decarb existed prior to cooling. What I was showing is, carbon in contact with liquid iron migrating into the metal...the other item I was showing is carbon being removed at one end of a 3" cylinder and added at the other end...the area in between showing a concentration gradient. It is possible the gradient became more severe during cooling and the top layer may have solidified last.

 

Jan

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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 B)

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

:D

Edited by Jokke

Jokke

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Jokke,

Thank you..it looks like Koraat has an interesting project as well. When you mentioned it was easier to melt high alloy steel than wootz I was a little surprised.Some day I will try to remelt some 440C in a crucible just to see if it will hold up to the heat.

 

Jan

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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

Edited by Jokke

Jokke

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Hi Jokke

 

i agree the high alloy melts are quite easy to melt !

my experience is small though... made 52100 + C = 1.9% carbon

over the course of forging i found it to be very difficult and had to cut ingot in half... then you had to be very careful not to overheat... it liked to crack when hot..

-but it did make a nice small blade...that etched very nicely... matrix was black and the white was very shiney

-at that level of Cr ..it will be all over the place ... should make a stain free knife or maybe a big headache :P

- i believe Achim has short video on youtube forging a stainless ingot...

 

the young fellow you post has some interesting knives !

- i tried to melt with coal a couple times, it is tricky to do... for me, it usually resulted in a hole in the crucible or not enough heat to melt.. just bad luck for me but others can do it

 

-by the way, i believe in Juha's study of wootz, he sand cast his ingots .... as long as there is enough time for dendrites to form, then it is good !

-for me, i'm abit chicken to play with pouring liquid steel (even though i have a silver suit ) there is no small mistakes with liquid steel :o

 

by the way... just a thought.. have you ever noticed that when you try to melt some metals that occasionally one will form an oxide that doesn't melt so easy.. even exceeds the melt point of that oxide (which is unexpected ).... i noticed this on occasion melting copper that an oxide will hold much of the charge together till well past melt point of the actual copper oxide ? Perhaps the iron charge in wootz is occasionally making a difficult oxide skin and the remnants are floating around in the wootz (perhaps leading to the gas pockets )

- the baffling part is that you can have 3 melts of the same type charge, 1 or 2 may become bubbly and at least 1 will be perfect? so something other than the charge can be the result of bubbly

- crucible, furnace, heat, moisture, also length of time for glass to cover charge

-

 

i read this long time ago but it is interesting from Bain's book on alloys

- look at the elements and the arrows.. this will show general trends for those alloys

 

DSC06374.jpg

 

i have used small amount of niobium for a wootz melt and it does turn out good and as you can see, it like to be combined in carbide...

-some of the studies i read will blame Mn for alloy banding in modern steels and it has the trend for being not as a carbide

 

very interesting chart

 

Greg

 

 

 

 

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

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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 B)

Edited by Jokke

Jokke

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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

:angry:

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 :excl:

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

:P

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

B)

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

Edited by Jokke

Jokke

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Crusty neo-industrialist, twisted-kilt, capitalist old fart here.

 

So this is what happens when I leave you guys alone for two seconds. I've always considered myself a blacksmith first and foremost. Being a blacksmith who actually makes a profit at what he does brings a certain amount of wrath upon me. "It just ain't right, he must be a capitalist"! LOL!

 

I make enough profit to allow me to tinker, and I love to tinker. I'm not so much into "high-tech" as I am "appropriate technology". Induction makes working at this so much more comfortable, and at 10 - 20% of the energy cost I probably have a smaller carbon foot-print. I sell the machines at just a little more than you would pay direct from China on Ebay. I go through them and test them before shipping, I make some needed upgrades to the electrical and I warranty them for a year - parts AND service. And I give all the hand-holding you need.

 

Crusty? Probably. Intolerant? Sometimes. Forgetful? What was the question again? Yeah, I manufacture tongs, but I don't mind spending a few hours showing someone how to make tongs either. I have public videos that show all my secret processes. :wacko: I enjoy showing what I do and how I do it - I really don't have any secrets.

 

On the subject at hand, the machines I normally sell are not suited to melting. At the frequencies these run, the penetration is rather shallow. Melting usually requires much lower frequencies and a great deal more power. Both equal big bucks.

 

On the other hand, this process does not require great speed either. Be fun to play with. While it might work for steel melting, I am under the impression that the Wootz pattern requires a very slow cool-down. Better achieved with a large heated mass like in a furnace. Once liquid, induction induces a stirring action to the charge, might be good, might not.

 

Introducing a lot of new variables into an already poorly understood process.

 

The evil capitalist counting his money (note twisted kilt):

 

Edited by nakedanvil

[font="Book Antiqua"][color="#0000FF"][size="5"][b]Perfection[/b][/size]

[i][size="3"]is achieved not when there is nothing left to add, but when there is nothing left to take away.[/size][/i][/color][/font]

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Hi Grant,

I'd recommend a 3,000 to 10,000 hz unit for melting..that is what I have...soon to be powered.

Though with a good heat shield and proper coupling of coil to crucible I have no doubt it could melt a pound or so of steel...you'd need a larger coolant tank I think though to take care of the water in the coil.

 

Ric

Richard Furrer

Door County Forgeworks

Sturgeon Bay, WI

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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

Edited by Jokke

Jokke

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so here come the pics

it is the last piece of wootz I made to a blade,

the second is made from a wild damasc from a friend (Micha Schick from Essen)

 

hope I made the pics small enough for everybody:

realorcopy (1).JPG

realorcopy (3).JPG

realorcopy (4).JPG

realorcopy (5).JPG

realorcopy (7).JPG

realorcopy (8).JPG

Jokke

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by the way, the blades are quite small, about 82mm of length both, 23 mm wide

Jokke

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Hi Jokke

 

the blade looks good .. getting a usable knife is the goal

 

what is the etchant that you use? pattern seems to be on the lite side

- was there some P in the charge ? I find that with some P in the charge it helps to resist the acid... sometimes multiple etches,followed with wet sanding with 2000grit can sometimes help out the pattern...

 

do you have plans for handle..? please post when you do more, it will be nice to see it wear the wood coat ! ;)

 

 

Greg

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Hi Greg,

did a fast grind up to 400 grit and a very fast Fe-cl etch on the blades

the wootzblade is waterhardened, direktly out of the forge, after doing some normalysing,

used the 60°C water besides the forge and it worked out well, no warping, straight as line

 

the damsc blade is not hardened yet, it needs some warm oil

thince I am into rebuilding an old house there is not much time for forgework

but I will restart under much better conditions soon, I hope.... B)

 

I just took out 2kg of old nails from the wooden floor that had been in the kitchen to be...

maybe I should try a smelt with those, like Adski did - they are all from the 30ties

and I got a present from one of the workers:

a 1,5meter piece of an old railroad, stamped 1899 ^_^

 

have to get back to work...

best regards

Jokke

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