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I Forge Iron

Patrick Nowak

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  1. The professor I learned the most from in college, Dr. Carroll Mobley, worked with Bob Maringer, the inventor of the spinning copper disk technique at Battelle before he came to the university. He had lots of stories about that process and he had us use a variation of it to make rapidly solidified solder strips just to show us how it changes the solidification behavior. My favorite story of his was when he used that technique to rapidly put tinsel on the family Christmas tree. A metallic glass is a glass because it lacks a crystaline structure. Most of the ones I know of are complex alloys and it is the high number of alloying elements and the atomic sizes of those elements that help to prevent the formation of the normal crystal structure. They do have fairly unique properties compared to normal metals. To the best of my knowledge the metallic glasses are really pretty thin due to the rapid solidification times required. As for single crystal castings, it has been a long time since I've given those any thought. I recall that control of solidification variables is critical. Also, you can get single crystals that are not the complext alloys needed for the metallic glasses. They are two very different situations. The reference to 1/4 inch grains was intended to indicate that they are very large by normal standards. Usually grain size is measured with a microscope at 100x magnification and the units are in microns. I do recall learning about glasses in general and the silica based glasses, though that too was a long time ago and is not my area of professional work. I have heard the statement about glasses being liquids and if given enough time they'll flow but I've also heard that the evidence for that (old windows) is based on a misunderstanding of the manufacturing techniques used and that old windows were in fact made with varying thickness. That makes sense to me if the panes were made by hand blowing since, in that case, the glass worker would blow a hollow ball, open the end and form it into a flat disk, all while the glass was still attached to either the blow pipe or the punty rod. In either case, the center of the disk was thicker than the edges so any panes of glass cut from that disk would tend to taper from the edge closest to center of the disk towards the outer edge. Once glass manufacture became more mechanized and they could make "float glass" then the thickness became uniform.
  2. Dian- Thank you for sharing the paper on forging of that hook. It does a nice job of explaining how grain size is affected when no heat treatment other than quenching from the finished forging temperature is involved. I've already given a pretty detailed explanation of how grain size is controlled by heat treatment. And you make a good point that the grain size being evaluated is indeed the prior austenite grain size. Generally this can be revealed by either an oxidation or carburization heat treatment which involves heating a small specimen to the austentizing temperature so that the austenite grains are outlined either by oxides or carbides. This allows you to see them under the microscope after the specimen has cooled, at which time you will typically have a ferrite/pearlite structure. It is important to note that both of these methods only demonstrate the capability of a steel to achieve a particular grain size when processed in exactly the same manner as the test specimen. When you want to know the actual prior austenite grain size you must etch for that without re-heating the specimen. That is usually done with a saturated picric acid solution. Grain size in large forgings: The company I work for can produce forgings from ingots approaching 200 tons and there certainly are other companies in the world that can go bigger. The biggest ingots I know about were between 600 and 700 tons and were cast and forged in Asia. In my industry, I cannot recall ever encountering a carbon or low alloy steel forging that was going to be used without some form of heat treatment. Therefore, the prior austentie grain size going into service would never be 1/4 inch, though in the as- forged condition prior to heat treatment that could be a possibility. Grain flow vs. Metal Flow- In the US forging industry "grain flow" is still the common expression, but that may not be true in other parts of the world. Grain Flow behavior will indeed be influenced by inclusions of all sorts as well as chemical segregation. Most of the inclusions present in the steels I deal with are manganese sulfides. Occasionally we do see an exogenous non-metallics but the grain flow behavior is mostly influenced by sulfides in the steels we are working with. Certainly if you have severely banded structures, say of pearlite and ferrite or bainite/pearlite that will contribute to the grain flow behavior. It is rare for our forgings to exhibit isotropic behavior no matter what the source of the raw material. In our work, the use of VAR/ESR materials is not done to achieve fine grains or get a part with uniform properties in all orientations but to ensure that non-metallic inclusion particles are as small and as few as possible. The act of remelting does not by itself ensure small grains. Solidification takes place quite slowly in those processes so in the as-cast condition you still have large grains. This is particularly evident on as-cast titanium which has beautifully colored grains that are often 1/4 inch or larger.
  3. Crystal boundaries are indeed a weak point in the crystal structure. I personally would not use the analogy of cold shuts or stress concentrators since I would put those other features into a different category, but in the sense that they help you understand that the boundary between crystals is a weak point, they are correct comparisons. The size of the crystals can be gaged by looking at fracture surfaces. When the steel being evaluated has a high hardness, as in the case of tool steels that are quenched and tempered, the fracture appearance can be pretty closely correlated to the ASTM grain size #. At one time there was a test call the Shepard Fracture test. It was possible to obtain specimens showing different fractures and these could be compared to the item of interest and to get a pretty good idea of the grain or crystal size. Today this evaluation is usually done with a microscope. A further note about edge packing. Steve makes an excellent point about the improved surface finish achieved by the process. One situation in which the technique could provide some benefit is if the blade being made was NOT going to be heat treated. This would be the case for some historical blades. there are quite a few examples old blades that show no evidence of heat treatment after forging. the reason is because the dislocations created by the process could remain (since there is no phase change and the work is done at fairly low temperatures). These dislocations will result in an increase in hardness relative to an item that has not been subjected to low temperature forging and this increase in hardness could give improved performance. When properly heat treated modern steels are used there is really no metallurgical benefit. However, there is a whole subset of industrial forge work called "cold forging" in which the forging temperature is kept below the temperature needed to have dynamic recrystallization. In these products, the dislocations created during forging do contribute to the final performance properties of the part.
  4. Let's talk just about grain size. To do that we first have to know what we mean by "grain" in this context. For purposes of this topic a grain is the same thing as a crystal. A crystal is just a group of atoms that are arranged in a repeating pattern. In the case of iron with no other elements, inclusions, impurities etc., iron can have two different atomic arrangements. One is body centered cubic and the other is face centered cubic. What this means is that atoms are arranged such that they form a network that can be broken down into cubes. Imagine a square frame completely filled with pool (billiard) balls. Each ball represents one atom. Now imagine a second frame of balls positioned on top of the first. The natural tendency is for the top layer to nest in the depressions between the balls of the first layer. Each ball in layer two is touching 4 balls in layer one. Adding additional layers in the same way gives you a stack of balls that is pretty stable. that is the body centered arrangement. If we balance the second layer on the first layer such that each ball in layer one touches only one ball in layer two and we stack additional layers in the same fashion we now have the face centered arrangement. There are metals other than iron that have these structures but for our discussion we are assuming iron for all the examples. In the iron system, the BCC or FCC arrangement is dependent on temperature and if we heat/cool pure iron under thermodynamically equilibrium conditions the change from BCC to FCC happens at about 1333 F. At very high temperatures, well in excess of 2000 F, iron will switch back to BCC, but that structure is not of significant importance to blacksmiths so I am ignoring it. Our stack of pool ball represents a single crystal. If we have other stacks that are next to the first, but not in the exact same alignment, then we have a new crystal or group of crystals. They can all be the BCC or FCC, but they have different orientations and are therefore each a unique crystal. The size of that crystal can be measured using a microscope and we know that some performance properties are influenced by the size of those crystals so it is good to know how to control that property. the size of a crystal generally increases with increasing temperature, but the RATE of growth is temperature dependent. Grain size will change slowly, or maybe not at all for practical purposes, at low temperatures. In general practice, we assume that BCC iron really doesn't change size with increasing temperature, though it may be measurable with the right instruments. Even if it does, it is not significant to what a blacksmith is doing. So, for practical purposes, grain size does not change when the grains have the BCC arrangement. When we heat iron above 1333 F, the BCC arrangement is no longer the favored arrangement and the atoms begin to rearrange themselves into the FCC form. This happens by a process call Nucleation and Growth. First, a tiny FCC crystal nucleates in a pool of BCC crystals. This little FCC crystal starts to grow by consuming the BCC crystals via a diffusion of atoms from one position to a new position. Of course, lots of new FCC crystals are nucleate at the same time and they are all growing by consuming the BCC crystals so pretty soon you have no more BCC crystals. If the temperature is just hot enough for the FCC structure to be stable, let's assume 1350 F, then the nucleation and growth will be fairly slow and will be even slower once all the BCC crystals are gone. If however, we heat up to some very high temperature, say 2000 F, now there is enough thermal energy to cause the FCC crystals to continue to grow by consuming each other. The thermodynamic driving force for this is the reduction of crystal boundaries. The fewer there are, the more stable the system is from a thermodynamic perspective. Growth will stop once the crystal size vs. temperature has reached a balance or equilibrium condition. Raising the temperature to say 2300 would cause additional growth until a new equilibrium condition had been reached. During forging, we generally start at a temperature of 2300 give or take a bit but then we start to deform the metal. When we do this, we are causing the atoms within each crystal to get knocked out of alignment. this misalignment is called a DISLOCATION. We can have an enormous number of dislocations within a single crystal since these crystals have thousands or maybe even millions of layers of atoms within each one. Each disrupted layer is a single dislocation. Dislocations cannot pass from one crystal to another. They are stopped by the boarder or boundary (we call it a grain boundary) between each crystal. They can also be stopped by other things within the crystal such as alloying element. Once a dislocation hits an obstacle within the crystal or at the crystal boundary it stops moving. New dislocations are formed and will move, but they will get caught the dislocations already stopped by obstacles so pretty soon you have this tangle of dislocated atoms and at some point you will not be able to put in any more dislocations. (This is why a paper clip breaks when you bend it back and forth while fidgeting in meetings). So, as dislocations build up within a crystal, that crystal is no longer in equilibrium and at some point, the number of dislocations will be so high that a new crystal will form to get rid of those dislocations. When new crystals form for this reason that is called DYNAMIC RECRYSTALIZATION. This is very common during all kinds of hot working operations. The actual temperature at which it happens and how fast it happens will be a function of how much deformation has been done (strain), how fast the metal was deformed (strain rate) and the temperature at which the forging was done. Dynamic recrystallization is different from the other type of recrystallization event because it does NOT depend on a change from BCC to FCC. Dynamic recrystallization happens when the iron is already in the FCC arrangement. How big the crystals will get after a dynamic recrystallization event depends on how many dislocations there were to start with since these really are a form of stored energy and how hot the iron gets. The more stored energy and/or the higher the thermal energy (temperature) the larger the resulting grains can be. So that is all super interesting, but where is the practical application? The practical application of this is in grades which do not undergo a change from BCC to FCC like the 300 series stainless grades. Controlling the process variables lets you control how big the grains or crystals will be in those materials. In the case of CARBON AND ALLOY STEEL (not pure iron) we can forge at low temperatures near the end of the job to add dislocations, trigger recrystallization and, by keeping the forging temperature very low, say less than 1600 F, we can keep the as-forged grain size small. This has very limited practical benefit with moderns steels, but if you are working with historical steels (bloomery steel, blister/sheer steel etc.) in which there are almost no alloying elements other than carbon such a practice can be helpful in ensuring the final grain size after heat treatment is small, which is beneficial for toughness. In modern steels, most contain very small amounts of aluminum or other elements that can be used to keep grain sizes small during heat treatment so that we don't have to limit ourselves to finishing forgings cold. The process works like this: Aluminum will react with nitrogen, both of which are frequently found in modern steels to make an Aluminum Nitride. Aluminum nitride will dissolve in austenite at temperatures over about 1800 F, so it is not a discreet particle during the forging process. Grain size during forging is allowed to change via the dynamic recrystallization process discussed above. Once the forging is complete, it is cooled to room temperature and then subjected to the heat treatment cycles. A normalizing cycle may or may not be done depending on a variety of factors but if it done, the piece is not heated above 1750 F. In the range from 1350-1750 BCC crystals transform to FCC crystals and will grow, but that growth will be arrested by the presence of the aluminum nitride particles, which act as fence posts at the crystal boundaries, pinning them in place. If the Aluminum nitride was not present, the crystals would continue to grow. After cooling from the normalize, the crystals revert back to BCC. The piece is again heated to a temperature above 1350, this time to 1650 F. New FCC crystals are formed, but this time they will not get as big as they did when heated to 1750 F because there is less thermal energy to push them to get bigger. At this point the piece is quenched and after that it is tempered. There is no change in crystal size during tempering because that is done at a temperature less than 1333 F. If an extra small crystal size is desired, multiple normalizing cycles can be done, but for this to have the desired effect, each one must be at a lower temperature than the previous. So that would look like this: Normalize #1 at 1750, Normalize #2 at 1700, Austenite for quench at 1650. In industrial forge practice, multiple normalizing cycles are the preferred method for controlling grain size in carbon and low alloy steels since there is more control over that than than the finishing temperature of the forgings. Note that low temperature forging is sometimes advocated in hand forgings of blades and in that field it is described as "edge packing". That is really a misleading term as there is no increase in density along the edge, but if it is done correctly AND the heat treatment cycles are handled properly it can help to give a final grain or crystal size along the edge of the blade. A more reliable method of achieving the same result is to use a steel of know composition with elements that will form grain boundary pinners. I already mentioned aluminum nitrides, but some others are vanadium and tungsten carbides and columbium (niobium) carbo nitrides. You really don't need much of these elements to get this effect, 0.01% usually is sufficient. If you are working with a high alloy knife steel you probably have much more of these elements than you need since they have extra high concentrations of these alloys for improved cutting performance.
  5. The question regarding heat treatment vs. grain flow: Grain flow is completely independent of heat treatment. The grain flow is set by forging and is not undone or altered by heat treat treatment. This is because the grain flow is largely a function of small non-metallic inclusions such as manganese sulfides as well as bands of varying chemistry which follow the contour of the forging. (Note that is not unusual at all to find steel that, at the micro level, has layers of alternating chemistry somewhat like a pattern welded bar). Steel forgings are usually subjected to some type of heat treatment as you noted, but those treatments don't affect the grain flow. They can effect grain size and the specific microstructures present which have a direct effect on properties like hardness, the various strength properties I discussed above, fatigue life, wear resistance and fracture toughness. Billet is just an intermediate shape between the raw as-cast product and the final forged shape. The billet may or may not be subjected to heat treatment depending on how it will be cut later and what grade of material it is. Quite often, there is no heat treatment but if there is it is usually subjected to a high temperature tempering cycle or maybe an anneal. Most other heat treatment cycles would be a waste when further forging is going to be done. The shape of graphite, or even whether it is present or not, is a function of both composition and processing. It is not unusual to see a range or spectrum of features within a single piece. Also, the cast iron can be alloyed to develop other properties besides just control of graphite shape. The simple way to tell a casting from a forging is that with a casting the various marks tend to be raised from the background while in a forging then tend to be stamped in. That is not definitive but is generally true. With respect to telling the difference between materials, a spark test is helpful. Cast iron in its various forms will have a different spark pattern than the steels. Also, steels will generally ring if tapped with hammer while gray cast iron will not. These are all just ball part trials but they can get you fairly close. They are not all non-destructive and telling the differnece between cast ductile iron and cast steel by site or the ring test could be pretty tough.
  6. That first number looks like an ingot letter followed by a heat number. There are several steel mills that use a 6 digit heat number but it is only meaningful to the steel mill that made it. Their melt records will not be available on the internet. If you could track down the original steel mill they could use that number to confirm the grade, but I suggest you see if you local scrap yard has an X-ray based hand held metal analyzer they could use to get you a ball park composition. With that, it should be easy to confirm grade. Patrick
  7. [MOD NOTE: The following was originally part of the discussion on this thread, but its detail and clarity call for it to stand on its own.] I'm going to jump in on this thread because there are several things that have been shared above which are not metallurgically correct. My apologies to the original poster as I know this material goes well beyond the question that was originally raised, but first I will address those questions. The original poster asked how to tell the difference between ductile and grey cast iron. Ductile iron will ring much like steel when struck while grey cast iron tends not to do that. that is not an absolutely definitive method as you could still have a steel part. A spark test can also be useful in making this determination. None of the various forms of cast iron discussed below is typically forged either hot or cold. The entire reason for casting the part to begin with to get the shape you want. Ductile iron could be forged, though that is quite rare. If you want to try it you need to heat the metal to a very dull red and use very light blows. Due to the high carbon content, the melting temperature is much lower than that of steel so it is easy to over heat. Additionally, the microstructures are not really suited to forging. If I had something I new was ductile iron I would probably try to adjust it without heat it. Now to address the incorrect information: 1. Cast Steel Tools: Tools Stamped "CAST STEEL" were made from steel which was first cast into ingots and then forged or rolled to shape. This started well BEFORE the Bessemer process was introduced. Bessemer (and William Kelly in the US) both invented essentially the same process in the mid-1800s, but that was NOT the first time liquid steel as used (See The History of Metals in America by Simcoe). The process was commercialized (but not invented) by Benjimen Huntsman in about 1750. There are at least two documented references to the same process that predate 1700. See work by Cyril Stanly Smith. The use of steel made by the cast steel process for tools was common and these were stamped CAST STEEL to separate them from tools made from Blister or Shear steels. I am not aware that Bessmer steels were used for these applications. Note that I have in my own collection plane blades which are stamped "CAST STEEL" and which I have examined metallographically. These are wrought iron blades with very small amounts of steel forge welded to them. They were made by Ohio Tool which went out of business in 1920. 2. Forgings vs. Castings: Before dealing with this question please know that I am a degreed metallurgical Engineer with 20 years of experience, 18 of which have been in the open die forging industry. The terms that have been used so far in this thread are not metallurgically precise and therefore there are some misunderstandings. The "strength" of a metal in metallurgical terms is usually one of several specific types of strength: Ultimate tensile strength, yield strength or impact strength. Assuming we are comparing a casting and a forging of the same steel alloy, size and shape they could have the exact same ultimate tensile strength and yield strength because these properties are a function of heat treatment, not manufacturing method. Where forgings are superior to castings is in impact strength and fatigue properties. These properties are a function of several different variables including heat treatment, grains SIZE, and grain flow. In carbon and low alloy steels the GRAIN SIZE is a function of heat treatment, so I can make a casting with the same grain size as that in forging if I choose to do so. What I cannot do with a casting is create GRAIN FLOW around corners, shoulders or other features which I can do in a forging. The grain flow is due to small micro inclusions and non-metallic particles being elongated during rolling or forging and then being bent around features during final hot shaping. This gives forgings characteristics somewhat similar to wood. When you split a log you always put the wedges in the end and try to separate the wood at the boundary of one growth ring and another. When done correctly the wood splits easily. But if you drive a wedge into the side of the log such that the force is applied parallel to the length of the log it will not split. Likewise if you are trying to split around a knot or series of knots you will have difficultly splitting the wood. Forgings are just like that. loaded in one direction they will have greater toughness than loaded at 90 degrees to that direction. Castings tend to have uniform properties no matter how they are loaded. 3. Steel castings: Steel castings were not widely used prior to the implementation of the Bessemer process. Though liquid steel was available prior to that point, it was made is small batches, typically of less than 100 lbs and was generally used for tool steels and other specialty applications. There are records of large ingots, multiple thousands of pounds in fact, being cast in both Sheffield and Germany, but not until the mid-to later 1800s. (See Sheffield Steel by K.C. Barraclaugh and Steel, Iron and Cast Iron Before Bessemer by Buchwald). Wide spread use of steel castings (that is solidified in the near final shape) was not occurring until the early 1830s in the US and the 1850s in Germany and England (see History Cast in Metal). The reason for this is because the molding material used for steel has to withstand much higher temperatures that the green sand used for cast iron. It took quite a while for steel workers to figure this out and identify the correct mold material. The melting temperature of cast iron is about 2100 F while that of pure iron is about 2800 F. The cast steel being made by the Huntsman process was usually poured into cast iron ingot molds so there was no concern about reaction between the liquid metal and mold material as there is when making a near-net-shaped casting using sand molding techniques. 4. Cast Irons: There are 4 types of cast iron: White Cast iron, Grey Cast Iron, Malleable Iron and Ductile Iron. All cast irons have much higher carbon than steels, usually well in excess of 2%, often approaching 3-4%. In white cast iron the carbon is mostly in the form of iron carbide, making the metal extremely hard, brittle and wear resistant. this was the earliest form of cast iron, likely because the alloying elements needed to promote the formation of graphite flakes (primarily silicon) was not present in early cast irons. Grey cast iron is a much more recent development. In this form, there is much less iron carbide and much more graphite. The graphite is in a flake like form. Because graphite is so soft, this form of cast iron can be considered "pre cracked" since the flakes act just the same as if they were internal fractures. This is why gray cast iron cookware can be so fragile. Malleable cast iron is made from white cast iron which is subjected to very long heat treatments that force the iron carbide to transform to graphite having a spheroidal form. this eliminates the brittleness of white cast iron and grey cast iron giving product which is actually quite tough. However, due to the very long thermal cycles needed to achieve these properties, this material has been replaced by a modern alternative-Ductile cast iron. this material was developed around 1950 and is dependent on the addition of magnesium to the liquid metal just prior to pouring it into the mold. When done correctly this forces the graphite to take on a spheroidal form which results in very tough, crack resistant material. When combined with the proper heat treatment, this material can have some properties similar to that of forgings. 5. Dislocations: A dislocation is not the same thing as a grain or a refined grain. A dislocation is a disruption in the crystal lattice at the atomic level. It is caused by any plastic deformation. During hot forging, dislocations form, but they go away quickly because they are not thermodynamically stable. They are removed by the nucleation of new grains (which are austentite grains by the way). Dislocations are only an issue (for good or bad) in parts which have been deformed at a low enough temperature that they remain in the structure. If you are not sure what a dislocation is, what it looks like or how it behaves, look up the Bubble demonstration by Bragg on you tube. It is from the 1950s and does an fantastic job of providing a visual demonstration of this topic. 6. Control of Grain size: When we talk about grain size we are really talking about the grain size of the austenite prior to cooling to room temperature. Actual grain size is a function of the temperature reached (it really doesn't have lot to do with forging). The hotter you heat the metal, the larger the grains will grow. In modern steel making, alloying elements are used to prevent grains from growing very large as long as the temperatures are below about 1750 F. This is true for castings and forgings. 7. As cast structures: When dealing with large cross sections, such as the big ingots I deal with (some on the order of 5 feet in diameter and weighing 100,000#) the as cast structures will be very different from the forged structures because the solidification time is so long. In these cases, you can indeed have as-cast grains or crystals which are very large and which are broken down by the forging or rolling process. But if we are talking about the fairly small casting the original poster asked about, there is no reason to think the grains would have to be larger than those in an item made by forging. 8. Info from the Milwaukee Forge website: While that information is factually correct it is not complete. they have intentionally selected pieces of data that promote forging over casting as a method of manufacture. they have not included anything about the grades, section sizes, types of forgings vs. casting etc. While I am 100% in favor of forgings (that's been my business for the last 18 years) those statements are extremely broad and are not qualified in any way. That makes them less than reliable in my book. Castings are often a fine way of making something. It really depends on the needs of the application. In general, forged or rolled metals will have better fatigue life, impact toughness (in certain directions) and ductility (in certain directions) than castings but all those things are highly dependent on a wide array of variables. Patrick
  8. H13 can be forged just like most other steels. The challenge is in getting it to move. Becuase of its composition it takes a great deal more power to work than a grade like 4140 or 5160. It is a superperb material for an anvil cut off hardy. I've made a few of them but I've alway used a power hammer for this work. In smaller sections like 5/8 and 3/4 you can hand forge it. You can even do it with one inch but you'd better have a pretty big hammer. The reason for using H13 in this application is because you can make the cross section thinner than you can with other materials which means you can more easily cut your work pieces, especially thicker cross sections. Also, because it is a heat resisting alloy, it will maintain its hardness at much higher temperautres than 4140 or 5160. I have found that even with thin section tooling I can cold cut stock on my H13 cut off. As a side note, tomorrow we will be forging some large diameter bar (27" OD) from ingots that start off in the 40,000# range. Patrick
  9. Contact Bob Bergman at the Postvile Blacksmith in Postville WI. He has rebuilt quite a few Nazel and C-burg self contained hammers and would probably know the answer. Ric is correct. Chambursburg has been out of buisness for a number of years. Patrick
  10. In the work I do, I find that I have much more control of the final size and shape if I forge one side and flip. If you are doing work that is prone to piping, such as the mokume I work, using the hit turn approach has a greater risk that you will make a diamond due to the fact that you have to very quickly get the piece square to the plane of the die while balanced on the bulged out spot. Though you have all those bulges when working one side and then flipping, you can get you be more sure of you alignment before you start the next pass. Additionally, when working laminated materials, the way in which you work the metal will affect the final appearance of the pattern. On large industrial forgings where I have a concern about piping, I advise the forge crews forge from square to round working the full length of one corner before rotating to the next corner because that alignment is so critical to the prevention of piping.
  11. Yes I did pre-heat significantly.Hard faced thickness was 2 passes in most areas since more passes likely would result in cracking. I used about 35 lbs of 3/16 rod to do that job, though that amount also includes the hard face of the square horn. If you search for a post titled "1050# fabricated anvil" in this forum you can find several pictures of that project and the details of how I made it. Patrick
  12. Elsewhere on this sight is a thread about an anvil I made. I did hard face it using Hobart Hardalloy 48. The face was 9.5 x 20. It took me 7 hours of welding to hard face it plus several more to do the grinding with a 9" angle grinder. The Hardalloy 48 is NOT a high wear risistance rod but does get into the mid 50s HRc which is just fine for an anvil. I did not have any cracking problems with this rod, but I have had those issues with much more highly alloyed rods are are designed to stress relieve by cracking.
  13. Another thing for anvil noise is to get a different anvil. Either a Fisher or something shaped like a Nimba. The Nimba shape won't ring as much and Fisher's, being cast iron with a steel face, have almost no ring at all. Patrick
  14. I broke the heal off of a 180 # mouse hole a few years ago. The original forge weld had failed for at least half of the width of the face though the face itself was still intact. I knew it was broken when I bought it and I got it with the intention of making it into a small double horned anvil. I had to cut through the face with an abrasive disc before I could break off the heal with a sledge. This leads me to believe that manufacturing flaws are the root cause of many of the broken anvils we see. I have also personally observed anvils in more than one shop that were "abondoned" as it were.This occurs when the shop activities transition from a lot of forge work to other types of manufacturing. The anvil stays in the building but is pushed of into a corner where can be used and abused by those who don't respect it as a forging tool.
  15. I started forging for the same reason something like 14 years ago. Because I was working with Thomas Powers (a frequent contributor) he was able to coach me through a damascus blade my second time at the forge. That worked becuase I'd already made numerouse stock removal blades and was pretty good with hand tools already and most importantly becuase Thomas is a patient and willing teacher. That being said, I would advise you to find a willing teacher in your area. I can give you a very detailed written description of how to make damasucs and enen go into detail on the metallurgical principles at work in the process but that likely will not be as helpful to you at this point as getting some hands on experience with a good teacher. There's no reason you can't jump right into a damascus project early in your forging career, but that will be facilitated greatly by finding someone who can show you the basics in person. Patrick
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