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  • #16
    Originally posted by bob ward
    Doing a bit more reading (googling) about sodium ferrocyanide, I gather that while tonnes of the product are used in food annually, Kasenit etc is banned in the average workshop here by Workplace Health & Safety (WHS) because of the high temperature decompostition products.

    Properly equipped heat treaters can still use it of course.
    Bob it seems this business sells Hardite powder, although it is a bit expensive

    It is right down the bottom on the last page http://www.ejwinter.com.au/catalogue...rials-8-08.pdf

    And this mob sell Sodium Ferro Cyanide although probably only in bulk lots.. http://www.quantumchemicals.com.au/P...45366919edoras
    Precision takes time.

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    • #17
      Originally posted by Ringer
      Bob it seems this business sells Hardite powder, although it is a bit expensive

      It is right down the bottom on the last page http://www.ejwinter.com.au/catalogue...rials-8-08.pdf

      And this mob sell Sodium Ferro Cyanide although probably only in bulk lots.. http://www.quantumchemicals.com.au/P...45366919edoras
      Ouch! $38.50 for 100 grams (about a quarter pound)! Last time I bought Harris Quick Hard was last summer and it was about $30 for a one pound container.

      For those interested in the MSDS for this and similar compounds see:

      http://www.harrisproductsgroup.com/p...Quick_Hard.pdf

      This or similar compounds used with common sense, good ventilation and as in the instructions should pose little problem.

      You might try welding supply houses or black smith supply. That is where I get the Harris product.

      cheers, Graham

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      • #18
        Originally posted by lazlo
        That doesn't necessarily extend to high temperatures, which could concievably free the cynaides from the metal (sodium) bonds, but sodium ferrocyanide is also a common component in welding rods, so that seems counter-intuitive.
        As you say lazlo, there is sodium ferrocyanate in both arc welding rod coatings and in Kasenit, both emit undesirable high temp decompostion products, but one is OK the other is banned.

        I suspect that WHS here may like to ban both, but the arc welding industry, and I include suppliers and welders here, is just too big and is found in every corner of industry, it simply can't be banned, its too pervasive. Just use good ventilation guys!

        But in house case hardening can be banned without little disruption or outcry because the hardening can go to the properly set up professionals. WHS score because they can point to their illogical ban, which most people don't know is illogical, as an achievement in their on going struggle for workshop safety.

        The small shops still have their tin of Kasenit hidden away of course and it still gets used.

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        • #19
          But is Kasenit banned in Australia bob???

          I cannot find any info where it is...
          Precision takes time.

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          • #20
            Ringer, Kasenite itself is not banned AFIK, but it has disappeared from the shelves because the small shops can't use it any more.

            Sodium ferrocyanide even has its own web page, and what can't it do!
            1. Pigment production
            2. Anti-caking additive in conventional salts and street (snow removal) salts
            3. Precipitation of trace metallic ions (for separation in chemical processes)
            4. Cleaning agents
            5. Corrosion inhibitors (for continuous processes in contact with soft steel)
            6. Steel surface treatment
            7. Galvanization (silver and pewter)
            8. Photographic development processes
            9. Fermentation of Citric Acid and Ascorbic Acid, etc
            http://www.sodium-ferrocyanide.com/

            I've looked through my notes and can't find the guys that sold the carbon based hardening powders. But it was an odd bod in their main range of products, which I think may have been lubricants, maybe Fuchs.

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            • #21
              Ironically, sodium ferrocyanide is used in dry chemical fire extinguishers to prevent caking of the agent. It is also used in air dropped fire control agents.
              Free software for calculating bolt circles and similar: Click Here

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              • #22
                CHC Super

                Ringer, the charcoal based case hardening powder is available from Fuchs Australia, it is listed half way down this page.

                http://www.fuchs.com.au/categories.asp?cID=22

                As an aside, I had no idea of the level of sophistication of quenching oils, Fuchs list 6 different quenching oils on the page.

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                • #23
                  And to take the discussion of sodium ferrocyanide a bit further, potassium ferricyanide K3Fe(CN)6 and potassium ferrocyanide K4Fe(CN)6·3H2O are similar and can also be used for case hardening.

                  Potassium ferricyanide is commonly used in photo processing (among other uses) as a bleaching agent. It is still available from Kodak in 1 lb containers (if you can find it) and also in small quantities as part A of a product called Farmers Reducer.

                  Potassium salts are generally prefered to sodium as they tend to work better however where price is an issue sodium wins out. That is why your "heart healthy" grocery products with "reduced sodium" have replaced some of the sodium chloride (salt) with potassium chloride and have upped the price.

                  Tread lightly and carefully if experimenting "outside the box". Your best bet is always to get a commercial off the shelf product and follow the instructions. This way you will save yourself a lot of time and grief.


                  cheers, Graham

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                  • #24
                    Case hardening is quite simple, it’ s been around for centuries. To do simple, but effective case hardening all you really need is something that gives off carbon (in the form of Carbon Monoxide, Carbon dioxide) when heated.
                    This can be raw bone meal that you get from the local garden center, leather, bone char, horse hoof, I’ve also seen recipes that used sugar. I have done simple case hardening with raw bone meal, leather, and charred bone, they all work
                    Put this compound with the part that you want to case harden , in an air tight container and heat to 1450 for a period of time then quench ….Simple.
                    Although, the stench that comes from raw leather & raw bone is something not easily forgotten. I highly recommend charring those outside first before using.
                    I have tried both barium carbonate and calcium carbonate in the mixes, didn’t see any difference with the addition of either.
                    No way am I trying anything with Cyanide in its name
                    The really hard part is case hardening for colors, and trying to match the specific colors and patterns that the individual companies attained back in the day.
                    Mike Hunter

                    www.mikehunterrestorations.com

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                    • #25
                      We are talking about two different processes here. Using carbon based hardening agents such as charcoal or other carbon containing compounds is known as carburizing. On the other hand, Sodium ferrocycanide is known as a carbonitriding agent since it contains large amounts of carbon and nitrogen and produces a high carbon case with a shallower nitride case as well. Using plain carbon such as charcoal will not produce the same results.


                      No way am I trying anything with Cyanide in its name
                      Don't be silly. Would you consider eating anything that is made up of 50% chlorine? You know, the same thing they used to kill people in WW1?
                      Last edited by Evan; 04-17-2009, 02:45 PM.
                      Free software for calculating bolt circles and similar: Click Here

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                      • #26
                        Originally posted by Evan
                        We are talking about two different processes here. Using carbon based hardening agents such as charcoal or other carbon containing compounds is known as carburizing. On the other hand, Sodium ferrocycanide is known as a carbonitriding agent since it contains large amounts of carbon and nitrogen and produces a high carbon case with a shallower nitride case as well. Using plain carbon such as charcoal will not produce the same results.
                        Oh dear Lord, not again.

                        Kasenit is a common carburizing compound. Like all carburizing processes, Kasenit must be applied above the austentizing temperature: 1500 - 1800F.

                        Nitriding is a specialty process that uses ammonia gas to create hardened nitrides in chromium rich nitriding alloys like Nitralloy. Nitriding is done at much lower temperatures (around 900F), so there's no warping of the workpiece, which is the primary reason it's used.

                        If Kasenit had any nitriding properties, you'd see a substantial increase in hardness if it's applied at 900F, and believe me, it doesn't.

                        Kasenit is a little Mom and Pop operation in upstate New York. Feel free to call and ask him

                        Kasenit Co
                        13 Park Ave
                        Highland Mills, NY 10930
                        845-928-9595
                        "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                        • #27
                          Oh dear Lord, not again.

                          Kasenit is a common carburizing compound. Like all carburizing processes, Kasenit must be applied above the austentizing temperature: 1500 - 1800F.

                          Nitriding is a specialty process that uses ammonia gas to create hardened nitrides in chromium rich nitriding alloys like Nitralloy. Nitriding is done at much lower temperatures (around 900F), so there's no warping of the workpiece, which is the primary reason it's used.

                          If Kasenit had any nitriding properties, you'd see a substantial increase in hardness if it's applied at 900F, and believe me, it doesn't.

                          Kasenit is a little Mom and Pop operation in upstate New York. Feel free to call and ask him
                          What does who sells Kasenit have to do with the process?

                          It's called salt bath carbonitriding and relies on Sodium ferrocyanide as the major constituent of the molten salts. It will not produce any appreciable effect at 900F since the salt must be heated to at least 1000 to 1100F for diffusion to occur.

                          Case Hardening : A unique feature of salt bath nitrocarburized layers is the monophase _-Fe_N compound layer, with a nitrogen content of 6-9% and a carbon content of around 1%. Compared with double phase nitride layers which have lower nitrogen concentrations, the monophase _-Fe_N layer is more ductile and gives better wear and corrosion resistance by improvement with case hardening. In metallographic analysis the compound layer is clearly definable fron the diffusion layer as a lightly etched layer. A porous area develops in the outer zone of the compound layer. The case hardness of the compound layer measured on a cross-section is around 700 HV for unalloyed steels and up to about 1600 HV on high chromium steels. Treatment durations of 1-2 hours usually yield compound layers about 10-20 _m thick (0.0004 - 0.0008"). The higher the alloy content, the thinner the layer for the same treatment cycle. Fig. 2 shows the relationship of layer thickness to treatment time with nitrocarburizing temperature of 580�C (1057�F).
                          See here: http://www.burlingtoneng.com/case_hardening.html
                          Free software for calculating bolt circles and similar: Click Here

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                          • #28
                            Originally posted by Evan
                            What does who sells Kasenit have to do with the process?
                            So you won't believe the guys who sell Kasenit when they tell you it's ordinary carburizing compound?

                            See here: http://www.burlingtoneng.com/case_hardening.html

                            Fig. 2 shows the relationship of layer thickness to treatment time with nitrocarburizing temperature of 580�C (1057�F).
                            So Evan, heat your workpiece up to 1057F, which is well below steel's austentizing temperature. Coat it will Kasenit as per the instructions, and quench it. It won't change hardness a bit. There's absolutely no nitriding going on, because Kasenit is just plain, ordinary carburizing compound.
                            "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                            • #29
                              So you won't believe the guys who sell Kasenit when they tell you it's ordinary carburizing compound?
                              Oddly enough the rest of the industry thinks differently. I'm not talking about gas nitriding. I'm talking about ferrocyanide salt carbonitriding. See the link I provided above. I think they may know more about it than the "mom and pop" operation.
                              Free software for calculating bolt circles and similar: Click Here

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                              • #30
                                Originally posted by Evan
                                Oddly enough the rest of the industry thinks differently. I'm not talking about gas nitriding. I'm talking about ferrocyanide salt carbonitriding. See the link I provided above.
                                Nowhere in that article, or even the entire site, does it indicate that they're using Sodium ferrocyanide (the active ingredient in Kasenit) for carbonitriding. In fact, there's not a single mention of "cyanide" anywhere on their web page -- they state that they use "salt baths" but don't indicate which chemical.

                                Google:
                                ? cyanide site:http://www.burlingtoneng.com/

                                Your search - cyanide site:http://www.burlingtoneng.com/ - did not match any documents.
                                "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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