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Hi everyone,

As the title states, Im having difficulty forging one inch square bars. Whats happening is called fishtailing I believe.

Im widening the bar for a small axe blade with a crosspien hammer with a striker buddy to speed thing up and Im getting cold shuts along the ends. Or I certainly will if I dont do something soon. There is only minor cold shutting along the future edge which would need a trim anyways, but there are some massive shuts in the making along the other two bar edges, the ones that are getting stretched apart from each other.

How to fix and avoid this altogether?

Is there a way to fix it now without grinding or any material loss?

 

Im sorry if this is too obvious to most of you, but this is the first time Im doing such a large shape deformation and the first time Im encountering this problem.

Thank you all for your help and understanding :)

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Pictures would be helpful, but if I understand correctly, my approach would would be to chamfer the corners of the stock back into itself as I draw it out. Keep the material hot and hit hard. That helps deform the material in the center of the stock also. With light hits or cold material, the surface deforms more than the center and it mushrooms more. The biggest thing is to correct the problem develops. The more it progresses, the more difficult it it to fix and once a cold shunt forms, a hot rasp is you friend. About the only way to fix a cold shunt once it forms is to take a welding heat and try to forge weld it solid, but I’ve only had luck with that once or twice.

Also, try to work from the center of the material out to the edges. A top fuller would be very helpful with 1” stock.
I hope this makes some sense...

David

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In addition to all of what Goods said if towards the end of your heat (while it's still got some color, but not enough to keep spreading) you set the piece up on edge and push the material back in it will help it keep it's shape. 

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I think you mean fish mouth. That's when both edges starts to fold in onto each other. Fish tail is when it fans out, like the cutting edge on an axe. Splitting comes from forging at too low of a temperature. Fish mouth is a normal occurance you must watch for and correct as soon as you see it. When you see it happening, forge the edge back towards yourself .

I start a forging like that with the other end of your cross peen. At a steep angle, forge both edges to a single centered edge. When you have done this, then use your cross peen to widen (fish tail) the piece to the desired length. This should prevent your fish mouth problem.

 

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Yeah, I meant fish mouth, sorry.

Edit: This part is meant for another atempt, Im posting some pictures of the current one.

Could I possibly start spreading out material not by laying my square bar flat on the anvil, but on an edge, 45deg from one flat side?

That way, at least in my head, there can be no fish mouth happening since there are edges on both sides and I might get a bit more material drawn out giving me a wider blade.

The only problem I can see in this case is the eye part of the axe. Having the piece tilted 45deg will leave one edge directly where Id need to punch my hole and not enough material from the sides...

This might not be such a problem Im perceiving it to be, Id like to hear your thoughts on the matter.

Could I forge on that part a bit to make it more suitable for an axe eye and how to go about it?

Edit: Here is the very rough forged piece next to the axe Im aiming to make:

 

 

20210601_193933.jpg

20210601_194016.jpg

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When you forge a taper, you always place your iron at an angle to the face of the anvil. And your hammer makes the same angle when it strikes your iron. That way you are making the same angle top side and bottom. The angle of the two equals the angle you want on your work.  And, at least I, always forge the taper on the end first 

For what it's worth, many axes are not made from 1" square stock. They are made from wide flat stock(strap), mild steel, then folded over and forge welded. The eye Is not forge welded and a piece of tool steel, the bit, is forge welded into the end. Then the eye is drifted to shape and size. I believe you are doing it " the hard way". Making an axe is a great way to learn forge welding. No matter what, if your piece of 1" square isn't a tool steel, you will have to do something about a good cutting edge. Mild steel, you might say, just won't cut it.  ;)

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Two of the main methods for axe forging, as anvil has hinted, are often listed by the method for forming the axe eye: punch/slit and drift, or wrap and weld.  In both cases I concentrate on forming the basic eye first, prior to any significant spreading for the bit end.  The eye can be somewhat roughly formed, but getting the material correctly isolated and relatively close to the final size is a really good idea.  In your photos it looks like you have started with spreading the business end first.

JLP services has a number of very descriptive videos of forging an axe head using the wrap and weld technique, as does Mark Aspery on the ABANA website.

Axes are really not suitable projects for beginners IMHO.  Size of billet and complexity of the forging are pretty challenging.  I recommend either starting with forging tomahawks, or even better, getting an older 2.5# ball peen hammer and drifting out the existing eye before forging down the business end to an axe shape.

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Ok, so there are three ways to deal with fish mouths that I know of. 
one, let it happen and trim it off

two, forge blunt taper on the end and in effect push the taper back into the mad as you forge instead of drowning it out from the mass.

three, start your taper back from the edge with a set down forging back tied the mass and drowning out from the set down to the edge. 
what is happening is that you are creating a ripple, like a wave at sea. So when your draw out from the mad toed the tip this wave breaks at the end forming a fish mouth. Forging a blunt taper then progressively making the taper more acute prevents the wave from breaking. Now buy setting down back from the edge and then drawing out you push material from the center of the stock out tied the edge, coursing the center of the cut edge to buldge instead of moving the surface. Buy the time you get to the edge the end has become convex instead of concave. Jenifer has a nice Video of drawing tapers that shows it 

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7 hours ago, anvil said:

When you forge a taper, you always place your iron at an angle to the face of the anvil. And your hammer makes the same angle when it strikes your iron. That way you are making the same angle top side and bottom. The angle of the two equals the angle you want on your work.  And, at least I, always forge the taper on the end first 

For what it's worth, many axes are not made from 1" square stock. They are made from wide flat stock(strap), mild steel, then folded over and forge welded. The eye Is not forge welded and a piece of tool steel, the bit, is forge welded into the end. Then the eye is drifted to shape and size. I believe you are doing it " the hard way". Making an axe is a great way to learn forge welding. No matter what, if your piece of 1" square isn't a tool steel, you will have to do something about a good cutting edge. Mild steel, you might say, just won't cut it.  ;)

I meant to ask would it have been better to draw out the blade by laying it on one edge, with that one diagonal being vertical on the anvil?

That way, I can utilize Existing tapers to a point on both sides and thus, hopefully, eliminating fishmouth on either side.

I guess that could work well enough for the blade, but I end up with the edges where the hole for the eye needs to be. Thats whats bothering me...

 

And I know axes arent typicaly made from 1in squares, but this little axe can take it. I havent finished forging on it and it can already fit more or less.

Its a 9-10 century battle axe anyway, it should not be very thick, so I have tons of material if the need arises to spread it a bit more. In fact, I might be left with decent bit of steel to grind off in the end...

I dont have access to the kind of stock you guys usually use for axe making, but the design would allow it, so why not use what I have at hand, eh? :D

I was kind of avoiding forge welding for a long time, but since I started using coal, I think it would be easier to achieve the prooer temperatures more reliably and evenly, so I might do a folded one in the near future.

and lastly, you are correct. This is mild steel. I dont intend to weld in a high carbon bit, I intend to carburize the edge part for about an hour, which should add enough carbon to through harden such a thin profile, so no worries there ;)

7 hours ago, Latticino said:

Two of the main methods for axe forging, as anvil has hinted, are often listed by the method for forming the axe eye: punch/slit and drift, or wrap and weld.  In both cases I concentrate on forming the basic eye first, prior to any significant spreading for the bit end.  The eye can be somewhat roughly formed, but getting the material correctly isolated and relatively close to the final size is a really good idea.  In your photos it looks like you have started with spreading the business end first.

JLP services has a number of very descriptive videos of forging an axe head using the wrap and weld technique, as does Mark Aspery on the ABANA website.

Axes are really not suitable projects for beginners IMHO.  Size of billet and complexity of the forging are pretty challenging.  I recommend either starting with forging tomahawks, or even better, getting an older 2.5# ball peen hammer and drifting out the existing eye before forging down the business end to an axe shape.

I never really intended for this to work out so well as did...

I dont have a pair of tongs at the moment, so leaving the thing attached to a meter long handle seemed like a good idea :D

And besides, I wasnt really sure how much material I would need for my blade, so I went for that first.

It turned out okay, so the next thing I did was to drill some holes and file them in to make a little slot where the drift will eventually go.

Currently, Im working on a new pair of tongs and when I complete them, its onto the drift next. Only then can I make the eye...

I know Im working a bit out of order, but I had free help that day, so I had to take advantage of that and forge out the blade fast :D

This piece is kinda like a tomahawk anyway. Only its European and way older.

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7 hours ago, Charles R. Stevens said:

Ok, so there are three ways to deal with fish mouths that I know of. 
one, let it happen and trim it off

two, forge blunt taper on the end and in effect push the taper back into the mad as you forge instead of drowning it out from the mass.

three, start your taper back from the edge with a set down forging back tied the mass and drowning out from the set down to the edge. 
what is happening is that you are creating a ripple, like a wave at sea. So when your draw out from the mad toed the tip this wave breaks at the end forming a fish mouth. Forging a blunt taper then progressively making the taper more acute prevents the wave from breaking. Now buy setting down back from the edge and then drawing out you push material from the center of the stock out tied the edge, coursing the center of the cut edge to buldge instead of moving the surface. Buy the time you get to the edge the end has become convex instead of concave. Jenifer has a nice Video of drawing tapers that shows it 

I kind of understood, but kind of didnt...

Ive been thinking on my own a bit and Ive read all your replies. Im starting to get the picture, but I still like the idea of using the diagonal to spread out the material without ever forming a fishmouth.

I use this kind of approach on arrowhead sockets. Usually gives me a bit more width to roll the thing around itself comoared to drawing a socket out with the little square flat on the face of the anvil.

But like I already said, that would mean that Ill then have to punch the eye along the diagonal as well. And that is whats bothering me the most...

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Punch the eye first, doing it after forming the head is a PITA! You can make bolsters to hold the head for drifting after it’s forged. 

I will try to draw up some illustrations as to how the steel moves to help you visualize what I am talking about. You can also go buy some modeling clay and “forge” it to get an idea how it moves: 

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16 hours ago, Dan_the_DJ said:

diagonal being vertical on the anvil

Sorry, this is confusing and I don't know what you mean. I would do it like I described 

16 hours ago, Dan_the_DJ said:

carburize the edge

Sorry, this won't work. You may mean case hardening, but this isn't the process. Case hardening is barely surface deep and the first time you sharpen your edge, it's gone.if you want an edge, you need to forge weld in a bit.

Learn how to forge weld. It's a necessary tool. Basically your approach will not work and forge welding is the key.

16 hours ago, Dan_the_DJ said:

dont have access to the kind of stock

Steel is cheap and even easy to find for free.

And like Charles said, punch or slit and drift the eye first.  

16 hours ago, Dan_the_DJ said:

I know Im working a bit out of order

Yup, and it rarely works out for the better when you do step 2 before step 1

 

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6 hours ago, anvil said:

Sorry, this is confusing and I don't know what you mean. I would do it like I described 

Instead of lying the square with one side flush on the anvil and hammering the opposite one, I want to turn that square bar on one of its edges, and draw the blade out like that. Im uploading a sketch to hopefully make it a little bit clearer...
 

6 hours ago, anvil said:

Sorry, this won't work. You may mean case hardening, but this isn't the process. Case hardening is barely surface deep and the first time you sharpen your edge, it's gone.if you want an edge, you need to forge weld in a bit.

Yes, thats what I meant. And I beg your pardon, but it does work. Super nice as well.
I always hear its not viable... Well not really. People just take it as is I guess. Ive tried it and it works just fine for me. Heres a link of a guy doing it: 

 

I followed his recipe with slight alterations, but its basically the same deal.
Dr. Fabrice Cognot used a similar method to make a viking age sword out of wrought iron, with limited success however. But his problem was that he added too much carbon (too much heat or too long of a bake time) which to my understanding made cast iron which then melted away his blade tip which only meant he had to make a shorter sword in the end. The point is, it does penetrate relatively deep. A few mm at least, which is more than enough for a sword, or my axe.

Okay... This thing wont quote you anymore. Ill have to do it manually...

"Learn how to forge weld. It's a necessary tool. Basically your approach will not work and forge welding is the key."

Yeah, I always avoided it when using charcoal. I just couldnt achieve the necessary temperature consistently. With coal now, it seems more manageable. So Im trying that the next time Im free.

"Steel is cheap and even easy to find for free."

Not in my country it isnt xD

I mean, you can find some, but shipping is abysmal to my house and there simply isnt a dimension that suits my needs. Its usually both, so yeah :D

20210605_213954.jpg

15 hours ago, Charles R. Stevens said:

Punch the eye first, doing it after forming the head is a PITA! You can make bolsters to hold the head for drifting after it’s forged. 

I will try to draw up some illustrations as to how the steel moves to help you visualize what I am talking about. You can also go buy some modeling clay and “forge” it to get an idea how it moves: 

Well, too late now. Ill try it as is, see what becomes of it...
Its a test piece anyway :)
Ill definitely do that on the next go around.

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My grandfather was from Serbia when he was 12.  Grandmother was from Croatia. They came to the US before WW1, met in Colorado in the 1920's and married. He was a coalminer.

What kind of forge do you have. What kind of fuel.

So, there are no garages(auto repair), general repair shops, welding shops, machine shops close?

I've seen that vid before. He leaves a bit to the imagination, not to mention questions he can't answer.

I'll stick to what I said. 

I thought that's what you meant. I call it forging on the diamond. You can forge it any way you want. ;) It's still far easier to slit and drift or punch the eye before you forge the blade. You said you drilled and filed the eye. File two flat spots top and bottom on the diamond, then drill and file your eye. You just need to brace your square stock so you drill thru on center. You might drill half way thru from both sides.

Hey, the bottom of the line is if you are having fun, do it however you want. The experience you gain, positive or negative is priceless.

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I used charcoal until now. I think Ill use coal from now on. The one I have access to is a little bit unsuitable imo. To much smoke and slag. It wasnt meant to be used in a forge, but it works fine. For starters, it lasts way longer...

The forge is a "V" type with a perforated pipe runing down the bottom to increase the length of heating area since I mostly work with longer, thinner pieces of steel.

 

There are a few metal working shops, but none work with hardenable steels. At least not simple steels like plain high carbon. 

Im not sure about your doubts about the method of case hardening Im using. I used it with great success in the past. The best one being making a spring from mild steel.

I cant atest to its longevity though. I guess we will have to see.

The real test would be this axe Im working on now.

 

Lastly, I totally agree that I picked the most labor intensive way of going on about it, but it was the only one that didnt include any forge welding. Ill try to remedy that in the future, but I first have to finish this one and see how it turns out :)

thanks.

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I have no doubts as to this process for case hardening. It is tried and true, not to mention traditional. I've used it myself for a few things, springs included. It's more what the vid implies. He implies, no, flat states, you can get penetration by extending time. Even tho this is true, it's impractible and has been so thru time. Can you imagine the amount of coal or any fuel you will use, not to mention the  control to maintain a proper temp for even a few hours, much less 8? And 8 hours will only give very slight penetration of carbon. You can check it out by learning a bit about contemporary metallurgy. In the past, this process was used to make high carbon steel. It was called blister steel. Blister steel was not done or considered finished by just using this process. Many pieces were case hardened using this process, then stacked and forge welded.this process was done a number of times to get a more or less constant amount of carbon throughout the piece. This is the reason high carbon steels were so expensive and not easy to come by. It's the reason that an axe, for instance, was made from wrought iron and had a high carbon bit forge welded in in order to make a good cutting edge.

Perhaps Thomas will add a few books/pdf's and comments for you to learn a bit more about this, and without a doubt, give you a better understanding than I can.

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I had the same issue with carbon distribution. By logic, the surface should absorb more than the interior.

But I wanted to know, could you solve this problem by heating that same piece of steel you just carburized in an inert atmosphere?

In my mind, the inerior would want some more carbon, while the exterior has it in excess. Since there is no oxygen or anywhere for that carbon to escape to, shouldnt diffusion take care of things, giving you an end result with more or less equal carbon content in all places, except maybe for the core if your piece is too thick?

Edit: I know of blister steel and how it was made, but Id really be interested to hear if you could make due using the way I just described. Its way faster, but certainly not better.

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Yes, heating in an inert atmosphere will allow the carbon to diffuse to an homogenous level if kept hot enough, long enough.  Of course you run into the issues like, grain growth, cost and time. (I would go with a muffle furnace or an inert atmosphere electric heat treating furnace.)

Deep Carburizing is different from Case Hardening even if it's been described as "case Hardening on steroids", An interesting book on the process is "The Cementstion of Iron and Steel" Giolitti which goes into the details including things like: "Can you use diamonds as a carbon donor?"  "Is it possible to carburize without CO?" and the interesting experiments used to find out the answers!

For a rather in depth look at how wrought iron was carburized commercially as it used to be done in the UK I can recommend "Steel Making before Bessemer", vol I Blister Steel"  Kenneth Charles Barraclough

Note that what most "experimental" work on such processes tend to ignore are the energy costs of doing them back in earlier times.  I've been a part of an iron smelting team but we didn't have to spend weeks chopping and hauling wood and then charcoaling it before we could start a smelting run!

When people tell me they have no access to medium to high carbon steels I ask them how they got their computer since there are *no* cars, trucks, buses, where they are?  Most shade tree mechanics have scrap piles with metals that would have medieval smiths drooling to use.

Now choosing to use archaic materials *is* a valid personal choice for certain reasons; but will you allow puddled wrought iron or osmond process or bloomery iron?  As the Japanese tatara furnace shows; a bloomery can produce everything from very low carbon wrought iron to high carbon steels (and even cast iron---which is generally considered a mistake!)   Going archaic is usually done for experimental reason and/or bragging rights.  It is not a  very effective way to make items commercially!

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