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Thread: Some san mai and experiments WIP

  1. #11
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    That is so cool man nice work

  2. #12

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    A word of caution on the mild over damascus. In thin sections carbon migration will occur from the high carbon damascus to the mild steel, it is just a matter of to whay extent. You could end up with the steel equivalent all the way through the biullet of approx 1050 or 1060 if you are not carefull.

  3. #13
    Looks really good. Emoto/neck looks much shorter than the passaround and should be much more comfy. Profile looks much better, tip looks cool. And the san mai looks good as well, thanks for the WIP. Nice work!
    "God sends meat and the devil sends cooks." - Thomas Deloney

  4. #14
    WillC's Avatar
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    Thanks Guys.
    Carbon migration is a good point and something i'm very aware of in san mai. Interestingly you can see the carbon which has leeched out when you polish against the grain with an edm stone. I expect finger stones would be great to bring this out as an additional effect above the san mai. Short of using a slice of nickel on the weld line, I accept a little carbon loss as part of the deal. All though a little migration is clearly happening at the weld line, I have never noticed any loss of hardness, performance of the steel, I have made allot of san mai blades, some in steel which only had 0.5%C in the first place. I believe this is because, I am not repeatedly overheating the billet, using a power hammer helps most here, that and good temperature control, grinding after HT helps prevent any additional carbon loss.
    I suspect the main candidates for excessive carbon loss are, poor temperature control, especially in a coke forge, and taking repeated forge welding heats.
    The bonus of san mai is that you can take the core steel harder and get away with it in terms of flex, (if you have enough carbon left) The core in the mild/damascus was testing a tad over 60hrc with a hardness file, so I know there was no excessive carbon loss in this case. It is a bit of a juggling act though, between core thickness vs decarb vs edge support from soft steel, but thats why its such fun.

  5. #15
    Carbon diffusion occurs very quickly because it's a very small interstitial atom in iron. Be careful in assuming it's not diffusing.

  6. #16
    Those are awesome! i love the look of damascus cored san mai great work man.
    -Randy Jr (forgot to log into my account )

    Inspired by God, Forged by Fire, Tempered by Water, Grounded by Earth, Guided by the spirit.. Randy Haas

    Availible Knives

  7. #17
    WillC's Avatar
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    I'm not assuming it isn't, there's no stopping it, apart from a barrier of nickel or an equal balance of carbon. I'm assuming that it is, and minimizing it as much as possible.
    Thanks Jr

  8. #18

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    I figured you knew but just threw it out there for a discussion point. Keep up the great work!

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