Making the Serrata...

Discussion in 'Knife Dogs Main Forum' started by zackerty, Mar 27, 2013.

  1. zackerty

    zackerty Member

    My name is Stuart Ackerman...

    In 2006 I started making investment cast 440C knives...

    Here are some pics from the first batch being cast...

    The ceramic shell surrounding the 16 wax knives.
    The shell about to be baked, and the wax melted out.
    The 440C steel melting,
    The wax melting out.
    The ceramic shell placed on sand, ready for the liquid steel.
    Waiting...feed me!
    Steel kisses the shell.
    Almost filled.
    One hour after the steel was poured.

    Then I started to play around with the basic shape and grind new profiles for testing...


    And a group pic of the bead blasted blades...before heat treatment...

    And some testing with the first tester...
    New 12mm hemp rope, oil and dirt soaked 12mm hemp rope, 18mm hemp rope, 8 tonne Spectra rope...

    The normal VG10 steel blade did about one eighteenth the cutting of the cast 440C. It would slice paper roughly, but not shave hair off my legs. ( My arms are bare...)
    The 3mm normal steel was sharpened on the med grey ceramic Fold-a Vee...
    The 5mm cast steel, on the DMT med Diamond...
    Both blades would shave print off a telephone book page, without piercing the paper...the normal steel a bit cleaner...
    The cast steel cut the ropes faster, and with less effort, and lasted much longer...and will still slice shavings off a piece of oak plank, whereas the normal steel will start to slice, and then choke up.
    The shavings below are a small proportion of the three shopping bags full of various rope shavings...

    And some finished ones from the first batch...
    Last edited: Mar 27, 2013
  2. zackerty

    zackerty Member

    And today's version...
  3. Frank Niro

    Frank Niro KNIFE MAKER

    Very interesting, and what a huge project !. You must know that David Bowie sold investment cast 440-C blades years ago. I did buy one or two as well as the bars he sold. Your process may give better metelurgical results than his. I found that the cutting ability of this material increased about 10% over regular 440-C with a proper heat treat and true cryo treatment. I'm sure that Elmax or M390 of today would out perform the 440-C cast of that time. Frank
  4. zackerty

    zackerty Member

    Thanks Frank...
    Yes, I know all about Boye and his knives...I do not know his HT for his Dendritic range...

    I worked out my process over a few years and I have tried casting other steels to see if I could improve the edge...somehow 440C seems to be the best...

    If I was rich, I would try them all, and who knows...also, I have a wife who watches me like a hawk...:biggrin:

    Sal Glesser of Spyderco has now licenced my process for his version of the Serrata...:5:
    I am due to receive a prototype for comparison testing with my own Serrata...
  5. rhinoknives

    rhinoknives Well-Known Member

    Very interesting work you are doing here.
    I also have one of the folders from Boye and have always been interested in the idea of casting knives but never had a place or the money to do it.

    I commend your work and congratulate you on your working with spyderco knives.

    I have always wondered about casting any of the CPM steels and if their composition would give any increase in prolonged edge retention?

    Keep us posted!

    Last edited: Apr 1, 2013
  6. zackerty

    zackerty Member

    After a long hiatus, I am doing more Serratas.
    Did a test run with 316 stainless testerday to check temperatures and flow rates versus cooling.
    Two molds, one horizontal and one vertical...

    Filling the ladle

    Into the mold

    Starting to cool

    After a while chatting and discussing the important things of life...
    Around 600° C at this moment in time... [​IMG]

    I broke the molds today and a had 90% success rate in complete blades.
    The actual casting for the 440C batch will be Monday 13 November.
  7. zackerty

    zackerty Member

    The waxes to be coated in the ceramic slurry to be fired...[​IMG]
  8. zackerty

    zackerty Member

    Attached Files:

Share This Page