Michael Cochran Posted August 22, 2015 Share Posted August 22, 2015 So I have a stupid question, im pretty sure I know the answer but need someone a little more knowledgable to confirm. While at work yesterday I had a guy tell me he knows a bladesmith from about 30 miles away from me. He was telling me that the guy sprinkles ground carbon on rr spikes while forging a knife to add carbon to make it better steel for a blade. I am under the impression that in order to carburize steel you have to heat the steel and soak it in a carbon rich environment for a given amount of time depending on what you want to accomplish. I am also under the impression that every time you heat steel, in this case a rr spike, you decarburize the outer layer. You also have to think about scaling. Even if he managed to add carbon by hammering it in wouldnt most/all of it be lost the very next heat? Im not an accomplished bladesmith but iirc what I've read it seems like what this smith is telling people is more than just a little puff of smoke. Quote Link to comment Share on other sites More sharing options...
HWooldridge Posted August 22, 2015 Share Posted August 22, 2015 Well, there is a product called Kasenit, which is a coating used for case hardening. Might be referring to that or something similar. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted August 22, 2015 Share Posted August 22, 2015 Yes you will generally scale it off faster than you can soak it in; and then there is the grinding.... Quote Link to comment Share on other sites More sharing options...
SoCal Dave Posted August 22, 2015 Share Posted August 22, 2015 I'm with HW on this. What ever he is adding will only have a surface effect. Kasenit is applied at a red heat and will not penetrate very far into the steel. I've used it to treat my blacksmith hardy helper dies and it has worked well, but the dies never are allowed to get very hot. Quote Link to comment Share on other sites More sharing options...
Michael Cochran Posted August 22, 2015 Author Share Posted August 22, 2015 Thanks for the quick replies. I don't want to tell someone something if there's a chance it can come back and bite me but I was pretty sure about this one. If it comes back up (I doubt it will) I'll try to find out who the smith is and see if I can talk to him directly to make sure if it wasn't something lost in between the demo and the recollection. Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted August 22, 2015 Share Posted August 22, 2015 There's a lot of guys that will take a myth and run with it. That's why it's good to study up. RR spikes aren't suitable for a working knife, there isn't a whole lot that can be done easily that will improve it either. Quote Link to comment Share on other sites More sharing options...
Michael Cochran Posted August 22, 2015 Author Share Posted August 22, 2015 There's a lot of guys that will take a myth and run with it. That's why it's good to study up. RR spikes aren't suitable for a working knife, there isn't a whole lot that can be done easily that will improve it either. I definitely agree and can only think of one way to make one into a serviceable blade (weld in a bit) and one way to make it decent (case hardening as mentioned above).i do wish I knew and understood why we humans are so fond of constantly repeating myths like they are. I enjoy ancient mythology but despise current mythology. It's hard to go online or talk to people and research some things because of all the the bad information you have to wade through to get to the good. Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted August 23, 2015 Share Posted August 23, 2015 Yes sir, I know what you mean. A little testing and that guy would find out that what he was doing didn't amount to a hill of beans. It's been my experience that few makers ever do comparative testing, heck I haven't run across many that actually had an EDC that they made. It's no wonder myths like that persist. Quote Link to comment Share on other sites More sharing options...
Frosty Posted August 23, 2015 Share Posted August 23, 2015 People prefer myths because real knowledge is work and you have to just get used to being wrong most of the time.However, I do have a sort of related question that could maybe even be tested on a RR spike. While adding carbon to steel by soaking in the forge is pretty unlikely what happens if we add a little dusting of graphite between welds?Will this not increase the % C in the join? Increasing the C % will lower the melting temperature perhaps making the join easier to weld. Being at welding temperature will incorporate the carbon in the same manner we know the mythical 200 fold blade is homogenized long before 200 folds.The previous statements and overall question make sense to me but I'm not a bladesmith and have never tested the hypotheses. It's something I've thought about before though. Thoughts anyone?Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted August 23, 2015 Share Posted August 23, 2015 Patrick? as I recall you've done Frosty's experiment Want to weigh in with your findings... Quote Link to comment Share on other sites More sharing options...
HWooldridge Posted August 23, 2015 Share Posted August 23, 2015 You could pack a mild steel RR spike in bone black and soak it at austenitizing temp for a while. That would yield a case of some depth (depending on soak time and temp) then the spike could either be forged into a blade - or folded and welded. This would be a slower and more fuel consumptive method that stacking low and high C pieces. Quote Link to comment Share on other sites More sharing options...
Michael Cochran Posted August 23, 2015 Author Share Posted August 23, 2015 However, I do have a sort of related question that could maybe even be tested on a RR spike. While adding carbon to steel by soaking in the forge is pretty unlikely what happens if we add a little dusting of graphite between welds?I had wondered if maybe that would do anythin or not. Even if it did actually make a noticeable difference I doubt it would be worth it. I believe you'll have too much time and fuel invested plus the amount of steel you'll loose to scale and cleaning the joints will leave you with a headache.I'm glad this is turning into more discussion than I expected. Maybe I'll end up learnin somethin really good. Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted August 23, 2015 Share Posted August 23, 2015 I once had the bright idea to mix case hardening powder with my borax. In theory it would add carbon to the weld zone which not only would increase the carbon of the billet but reduce welding temperature. It was a failure, while in theory you'd think it would work, the borax didn't desolve the case hardening powder so the weld got contaminated. It might work with charcoal dust, I might revisit this one day when I'm bored and have nothing better to do. Quote Link to comment Share on other sites More sharing options...
teenylittlemetalguy Posted August 23, 2015 Share Posted August 23, 2015 I once had the bright idea to mix case hardening powder with my borax. In theory it would add carbon to the weld zone which not only would increase the carbon of the billet but reduce welding temperature. It was a failure, while in theory you'd think it would work, the borax didn't desolve the case hardening powder so the weld got contaminated. It might work with charcoal dust, I might revisit this one day when I'm bored and have nothing better to do.I am in the right place at the right time for once. I got that bored one day and I am here to tell you that charcoal dust in borax is awesome. It is my one of my most favorite homemade fluxes. It is VERY important to make it fine dust. Gains of sand sized particles cause other issues.It significantly lowers the welding temp needed to make a weld. I have even burnt steel in my gasser while using it because of lower melting temp. It makes welding thin stuff, like say 1/16" strap much easier in a gas forge. Quote Link to comment Share on other sites More sharing options...
cliffrat Posted August 23, 2015 Share Posted August 23, 2015 A couple of things:1. Not all railroad spikes are created equal. While most are mild steel very often you will find some that are mid to high carbon. Ever wonder why some spikes have letters on the head? That tells you what "grade" steel the spike was. Evidently there are different grades for different jobs. I think there are at least two types that are 1070 or higher grade tool steel. These make decent knives.2. Frosty asked:People prefer myths because real knowledge is work and you have to just get used to being wrong most of the time.However, I do have a sort of related question that could maybe even be tested on a RR spike. While adding carbon to steel by soaking in the forge is pretty unlikely what happens if we add a little dusting of graphite between welds?Using a graphite spray between pieces is common practice, especially for multi-bar patterns or patterns that require "stacking". Using kerosene or diesel fuel accomplishes the same thing. The carbon layer deposit avoids the "white lines" that often appear in multiple bar welds, mosaics, etc. You can use any pure graphite spray, but it has to be the "dry" type and cannot have any silicone in it like some spray lubes do. That will definitely jack up your weld.3. I think the idea of hammering carbon into the steel is archaic science. The smiths in Europe during the middle ages tried this because they hadn't figured out how to get the steel hot enough to melt and absorb the carbon. So, they tried to get it as hot as they could, and hammer it into the steel. Very small amounts of success with that. Steel will absorb some carbon in a reduced atmosphere, like at the bottom of the coal in the forge. (I think this works anyway). It has to do with carbon migration and available oxygen. In the bottom of a fire there is very little oxygen for the carbon molecules to attach to (it's all used in combustion), so they "migrate" to the iron atoms instead as they are released through combustion. In the upper portion of the fire, (the oxidation layer) the carbon attaches to the excess oxygen and forms either carbon monoxide or dioxide. I think that most of the scale you see on your steel during forging, is coming out of the fuel, not out of the steel. Quote Link to comment Share on other sites More sharing options...
Dogsoldat Posted August 23, 2015 Share Posted August 23, 2015 Not to be a pain, but with point #3 typically the bottom of the fire is were the most oxygen is as that's were it's coming out of the tuyer. I have understood the closest to the air supply is your oxidizing flame, half way up should be in the neighbourhood for a neutral flame and the upper portion furthest from the air supply will be carburizing. And scale is a function of hot iron reacting to oxygen. Quote Link to comment Share on other sites More sharing options...
Black Wolf Posted August 23, 2015 Share Posted August 23, 2015 take that RR spike and heat it and split it down the center and Lay in an 8ths of inch of 1095 and weld it back up and forge out that knife and hang onto it if you ever meet that old boy show him , you will have a friend for life as long as you dont tell him how you got that sharp edge on that rr spike knife Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted August 23, 2015 Share Posted August 23, 2015 Cliffrat, could you give reference to those "high carbon" RR spikes. There was a link someone posted here years ago to the actual government specs for RR spikes and there were none listed above .3C. As far as I've ever found, and I don't mess with them much if any, very old RR spikes (pre-26 I've read) are wrought. From '27 to mid '70's they were mild steel. And in the mid 70's they changed them. The newer spikes were marked "HC" but are just .3%C. I tried to find that link, but there's a lot of RR spike articles. If anyone knows where it is, please link. Quote Link to comment Share on other sites More sharing options...
bigfootnampa Posted August 23, 2015 Share Posted August 23, 2015 As far as I know those "HC" railroad spikes are still pretty soft steel. Low carbon levels are only part of the problem IMO... copper in the alloys adds weather resistance, but also makes the steel noticeably softer! So good for stuff that needs to withstand weathering... like gate hardware. Not so good for any cutting edges. Typical rebar is significantly better for blades... though still minimally serviceable. Quote Link to comment Share on other sites More sharing options...
cliffrat Posted August 23, 2015 Share Posted August 23, 2015 Not to be a pain, but with point #3 typically the bottom of the fire is were the most oxygen is as that's were it's coming out of the tuyer. I have understood the closest to the air supply is your oxidizing flame, half way up should be in the neighbourhood for a neutral flame and the upper portion furthest from the air supply will be carburizing. And scale is a function of hot iron reacting to oxygen. Thanks for the clarification Dogs. You are right it does depend on where the O2 source is located and most forges have the blower entrance in the bottom pointed up, which would mean that there probably isn't a decent carburizing layer anywhere in that fire. I don't think the upper layer is any less oxidizing than the bottom. There is too much available O2 in the atmosphere. Stick that steel in a hardwood or charcoal fire with no blower and bury it in the bottom of the coals, you might see some added carbon, but how much and how deep will it penetrate? Could be a fun experiment, but I'm way too lazy for that and I don't feel like paying a lab to test the results accurately.JM: I took a couple of those HC stamped spikes, forged them out flat, brought them up to critical and quenched. Then I did a breakage test. One snapped in half the other one bent over and cracked. Some of them are hardenable and others aren't. The truth of the matter is this: If you want to make a decent knife that is going to get some serious use, use a known steel and heat treat it appropriately, even if you only insert the tool steel between two layers of mild. If you are making craft sale knives that may see some use, but are probably more a conversation piece than anything else, any RR spike will do, The ones with a higher C content will do better than others. Oh and BTW, here is a link to almost everything you ever wanted to know about introducing carbon into steel:http://steel.keytometals.com/Articles/Art114.htm Quote Link to comment Share on other sites More sharing options...
Michael Cochran Posted August 23, 2015 Author Share Posted August 23, 2015 I have seen people add carbon by placing the steel in a closed container with a carbon source soaking it at high heat. I've also seen where it was done in a side-blast charcoal forge by placing it under the tuyere. I've never tried either method, I personally just use salvage steel for my tooling and bought steel for knives.I've never heard anything about rr spikes being good for knives. I've always heard no matter what they were ('HC' or otherwise) there isn't enough carbon and I've left it at that. Personally I don't see the point or fascination in using them for knives. Quote Link to comment Share on other sites More sharing options...
Kal Posted August 23, 2015 Share Posted August 23, 2015 A neighbor of mine wants a RR spike knife for his son. I know that the base steel of spikes makes poor knives but is it possible to run a layer of weld along the edge before finishing the forging to give it a layer of harden able steel? Quote Link to comment Share on other sites More sharing options...
Michael Cochran Posted August 23, 2015 Author Share Posted August 23, 2015 A neighbor of mine wants a RR spike knife for his son. I know that the base steel of spikes makes poor knives but is it possible to run a layer of weld along the edge before finishing the forging to give it a layer of harden able steel? Like I mentioned further up, you can weld a carbon steel bit into the spike. Done properly you can have a good edge steel much the same way old axes were made. Quote Link to comment Share on other sites More sharing options...
Frosty Posted August 23, 2015 Share Posted August 23, 2015 Wow, this took off didn't it? Cool. I'd forgotten you use borax and charcoal powder flux Tristan, just slipped my mind when I posed the question. I can attest to Tristan's home brew flux, it's as good as any commercial flux I've used.Kal, forge welding a high carbon bit in a spike is the only reliable way I know of to get good edge holding properties out of a RR spike. However, I've never heard of anyone running a bead of high carbon welding rod on one so I just don't know how or if it'd work. If you experiment with the process please keep us in the loop.Packing iron in a sealed container with carbon and often other secret ingredients has been done for millennia. Brought to near melting temps the result is "Blister steel." Bringing it to melting temps results in "crucible steel."One of the reasons items forged from RR spikes is so popular is folk know what a RR spike looks like and they can see the plastic transition from spike to whatever the finished product is. It's proof positive they can confirm by eye and feel that someone formed STEEL like modeling clay. RR spike products are popular at demos and such.Uh, I don't know how many bits that is but it's my latest input. Heck, I just feel pretty good the questions seem to have turned into a hopefully useful thread. Too Cool. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
wpearson Posted August 23, 2015 Share Posted August 23, 2015 found thisThomasPowersSenior Moment Member; Master Curmudgeon Members 19,609 postsLocationCentral NM/El Paso TX Area, USA Posted 11 Jan 2007 · Report postFrom a post I saved away years ago:"American Railway Engineering Association's Specifications for Soft-Steel Track Spikes. Original document, 1926, revised last in 1968Two classes of track spikes are given specifications, both low carbon and high carbon. Two sizes of track spike are identified, one of 5/8 inch square shaft andone of 9/16 inch.Page 5-2-1. "A low carbon track spike will not contain greater than 0.12% carbonnor greater than 0.20% copper.Page 5-2-2. Section 6a.Bending properties: The body of a full size finished spike shall stand being bent cold through 180 degrees flat on itself without cracking on the outside portion of the bent portion.Page 5-2-2 Section 11. Marking. A letter or brand indicating the manufacturer shall be pressed on the head of each spike while it is being formed. When copper is specified, the letters "CU" shall be added.Page 5-2-3: Specifications for high carbon steel track spikes 1968. Carbon not greater than 0.30%, nor greater than 0.20% copper. Page 5-2-4. Section 6a. Bending properties: The body of a full size finished spike shall stand being bent coldthrough 120 degrees around a pin, the diameter of which is not greater than thethickness of the spike without cracking on the outside portion of the bent portion.Page 5-2-5 Section 11. Marking: A letter or brand indicating manufacturer and also the letters "HC" indicating high carbon, shall be pressed on the head of each spike while it is being formed. When copper is specified, the letters "CU" shall be added."Additionally included in a fax to Mike Blue by the gentleman at Wellington industries, a division of Sheffield Steel:"Because of the bending tests required, the carbon content will not be greater than 0.30%. After all, brittle spikes would not be desirable as a track spike. Abent spike still holds the rail while a fractured spike would not. The consequences for the industry would be too great to consider. However, we refer to them as high carbon, they are not within the range of steels known as high carbon or hypereutectoid according to the steel industry standards, and have not been since at least 1926, when most track spikes were previously manufactured from wrought iron.""I'd go with the spring stock myself!Thomas Quote Quote Link to comment Share on other sites More sharing options...
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