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Cracked anvil


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I recently bought a 100 lb. Fisher anvil from 1883. When I bought it, it looked liked it had been badly mistreated. I searched forums and took the most common advice on how to fix the anvil, and now have 3/4 inch long cracks transverse to the weld, a lot of it pre existing in the hardy etc. I noticed them buffing the face with a 80 grit sandpaper, and then did a penetrant test on it. What should I do? Should I just leave it alone, or are these cracks going to keep getting longer? TIA

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I dont know if it works on anvils or not but on alot of things a person drills a hole at each end of the crack it will stop. The problem i see with an anvil is you are dealing with a 3 dimensional crack and you wont be able to follow the crack end with the drill bit. I dont know how you would fix it but it would be good information to know.

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First, you need to find out how big the crack actually is, such as Johannes has said. and like Johannes said, if it runs too deep, it can't be properly fixed. But, if the crack is only face deep, then you can grind it out and re-weld it in. I, personally, wouldn't use mig though. In my experiences in welding (which is what I am attending school for by-the-way) mig does not have a high enough penetration to accomplish what you want to do. I would stick weld it first. But since you probably don't know the metal's composition, you can't exactly match the electrode to the base material. to ensure penetration of the two pieces, (being the crack has separated it) I would use a E-6010/E-6011 stick electrode for the first pass. The E-6010 is used with DC+ only, and the E-6011 is used with DC+ or AC current. Then i would use a E-7018 (which can be used on DC+ or AC) for the filling of the joint. Then, for the final pass, I would use mig. But instead of using ER70S-5, I would choose a hardfacing wire from lincoln electric. something with a rating of about 52-58 on the rockwell C scale. And in doing this, be sure to keep a preheat on the anvil of about a dull-red in color. while you're at it, I would go ahead and hardface the rest so you don';t have any hard spots from the preheat and make sure you make it SLOWLY cool down with post-heat treatment.

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Hi Black Ink. It looks like you are kind of like me. You surf the Internet looking for some advice, and then take either the most popular hit or the average of all hits. Sometimes, the average is not the best idea. For example, if someone recommends 6010 and someone else recommends 7018, it may not be the best idea to look for (7018+6010)/2 = 6514. :) I don't think this rod is commonly stocked.

I would pay a lot of attention to what Thomas (my hero) says. First, don't try to reforge an anvil with a cast iron body. Also, don't try to heat the top red hot as a preheat. Thomas is right. For most steels, this would ruin the hardness. There are some hot work steels which can take this treatment, but these alloys are fairly exotic, and are not likely to be found in the top plate of an anvil.

I have noticed a lot of people on the Internet saying that anvils have to be preheated to red, else the weld beads will crack off. This advice is somewhat misleading. I can believe that this advice is sincere, if one thinks about the experience that is behind it. But, sometimes you have to think for yourself. First, do you ever see this advice from a "reputable" source? For online information, I like Bohler Uddeholm. They have an outlet in my neighborhood, but their prices are a little steep for me. Think about why this fellow posting on the Internet is getting underbead cracking when he does not preheat to red. Is it because of lack of preheat? Or is it for some other reason that excessive preheating seems to help ;)?

Now it is clear why I don't wish to pay $2 per pound for an anvil which has a lot of damage and weld repairs around the hardy hole. It is just too risky. This kind of anvil is worth $1 per pound, but around here, you can't buy it for that. You cannot even buy half an anvil for that (no heel or no horn).

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FRo, your post and a couple of others I have some questions. Youmentioned you sought help for repairs and then youhave a crack? CAn I read that to mean that you attempted a repair and then developed a crack? Not in any way criticising, just trying to figure out if it is old or new? If it happened as part of the repair ,how was the repair done? Knowing this may give me and others more info as to how a fix may be done. I have welded a lot of anvils with edge damage, I do not preheat and all have worked out fine. I use only 7018 stick rod. It is a work hardened steel I weld a very short area then pein really well then weld another spot away from the first. A word of caution with 7018, You must get the rod suited to your welder. They make both and ac rod and a dc rod and they do not interchange. My welder is ac. I buy 7018ac. Let us know about the above if you would like more help, Or more confusion as you see it, Rich

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I, personally, wouldn't use mig though. In my experiences in welding (which is what I am attending school for by-the-way) mig does not have a high enough penetration to accomplish what you want to do.


It depends on the heat, gas, and wire composition. As for strength, take note of the light poles and traffic signal poles, as well as many of the high mast, sports lighting standards around the US, Canada, and many countries in Europe as well as China. They are all welded with MIG. The remainder are welded with submerged arc, another form of wire fed welding. MIG is what I did for 20 of my 24 years at a major lighting and transmission structure manufacturer. MIG does penetrate when done properly. BTW, I agree with Rich. If you're going to use stick, 7018 is the way to go :)
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Well, I can say that my comments are based on firsthand experience - not beating a drum but I have repaired over ten but less than twenty anvils - can't be more specific because I didn't keep track. The main "battle" anvil I have in the shop now was completely recovered with a high carbon plate and heat treated over twenty years ago and has held up to heavy regular use with no cracking or breakage.

Surface cracks can be successfully welded with MIG - and 7018 - and probably a few other things. Old anvils are basic alloys so are pretty easy to weld to but the high carbon in the face can leave a heat affected zone which may break out later. The simple wires/rods have a tendency to blend well so you don't have a weird color zone like you might with a hi-alloy that contains manganese or nickel elements.

Every one I repaired needed some prep so the grinding and cutting will add some preheat but I used to spot heat cracked or broken spots to about 300-400, what I call "spitting temp" - or where it will sizzle water drops. Not very scientific but it seemed to work every time. More importantly and seldom mentioned is the need to clean the crack thoroughly. At the very least, it should be wire brushed, sand blast is better. Active rust under a fresh weld can make it fail.

There has been a lot of info posted on this subject. You might want to do a few searches for some additional opinions.

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Thanks for all your advise.I'm gonna take it into work and have a P.M.I test done on it and find out the material.Then I'm gonna use a welding procedure book that I got from a boiler rat friend of mine.I'll take pics,and keep everyone informed.I might even be able to have a rocwell test done on it ,does anyone know what the hardness should be?

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