Anvil rebound,- horse poo?

[emtor]

Well,- THIS video link removed due to language on Youtube claims just that . . . anvil rebound is horse xxxx.
The video further says that blacksmiths prefer anvils with a good rebound because it makes the hammer jump back up and therefore saves energy for the blacksmith's arm.
In my opinion (I might be wrong), rebound has to do with Isaac Newton, and that any action produces an equal reaction.
So, when the hammer hits the workpiece from the top, an anvil with good rebound will hit the workpiece back from the surface of the anvil with a force depending on the rebound.
Now,-is it true that rebound is of no value in an anvil, and should I trust Isaac Newton or the xxxxxxxxxxxxxxx on Youtube?
BTW,-both my Swedish anvils have rebound a bit above 90%.

[George N. M.]

Emtor,

There has been a lot of discussion about the value of rebound.  The accepted wisdom is that  high percentage of rebound is better.  Personally, I don't think that it makes that much difference because you are hitting a plastic substance, hot iron, which should absorb all or as nearly all of the energy in the hammer blow.  All you want in an anvil is an immovable object which will not absorb any of the energy which should have gone into deforming the hot metal.  You aren't supposed to hit the anvil.  You are supposed to be hitting the hot metal.  Unless you have the habit (which I have always considered odd and unnecessary) of tapping the anvil between blows to the metal.  Maybe rebound would do something positive then.

I suppose that rebound may have something to do with energy that passes through the work piece and is internally reflected back to the surface but I can't believe that it is enough to make any substantial difference.

An anvil with good rebound may also be less susceptible to damage or wear but I don't think that it does much for the smith.

I think the largest consideration is the weight of the anvil and stand versus the size of work being done on it.  If you are doing small work such as jewelry on it a small anvil of 25 kilos may be all that is needed.  If you are working with 50 mm square stock a 150 kilo anvil may not be large enough.

"By hammer and hand all arts do stand."

[JHCC]

My personal theory is that people confuse the rebound of a hammer from a bare anvil with the actual benefit of hammering hot steel on a live anvil vs a dead one. It's quite true that hot metal absorbs the rebound and therefore does NOT "lift the hammer" more easily. However, hot metal absorbs the rebound by deforming slightly more than it would on a dead anvil (such as solid cast iron) with no rebound. The amount of that increase is very small, but over the course of a day's smithing, it really does add up.

[ThomasPowers]

One other factor is that hot steel is not totally soft and some alloys are quite stiff under the hammer; work some D2 or even 5160 and see if all the energy goes into the workpiece!  So are they comparing how quite soft WI or mild steel works or a high alloy steel?

I once owned a cast iron ASO due to a theft right before a museum demo and I found that the face would deform under 5160 being worked at orange heat.  That was a clear indication that a harder face would have put more energy into the workpiece!

Now a better question is what would a good trade off between hardness and brittleness vs softness and toughness be for an anvil's face?  I have found that I enjoy hand forging on my harder faced anvils more than on the softer ones.  Perhaps my feelings would be different if I were doing a lot of large heavy work with strikers and damage to the anvil's face was a concern.

Please remember that Youtube videos tend towards Sturgeon' law in it's strict construction!   Few I have seen involve a well designed experiment that controls all the variables possible!

[anvil]

Anvil rebound does not affect your forging in any significant way.

The laws of physics absolutely apply. 

 

[ThomasPowers]

Rebound is a function of face hardness which does affect your forging---try forging on a puddle of water!

[anvil]

You are correct. Rebound is a function of face hardness. 

However, whether you forge a puddle of water or a piece of iron at forging heat, rebound has little effect on your forging in any significant way.

The hardness of your face(tough, not brittle) affects the longevity of your anvil, meaning how long you can use your anvil between the need to reface

 

[ThomasPowers]

Do you believe face hardness has an effect?

[anvil]

I added to my statement above that answers your question. 

It affects wear on the anvil face 

 

[ThomasPowers]

So have you worked on a cast iron anvil where the face dented under the material you are working hot?  I have; it was definitely not a positive experience and so I would have to say that the face must at least be harder than the hot material you are working!

[Frosty]

If your anvil makes a sound under HOT steel when struck it's reflecting impact energy imparted by the hammer through the stock. Impact energy is reflected by the far surface and returns to the face at the speed of sound in the material your anvil's made from. Anvils that actually ring for a second after being tapped are resonating,(ringing like a bell) the compression waves are rebounding between opposing surfaces until the energy dissipates. 

The harder the material the more efficiently it will conduct the energy. PERIOD. Even materials that don't resonate, harder is a better conductor of sound or seismic surveys wouldn't work.

I have an old ASO rusting in the saplings, someone gave me years ago. Anyone who'd like to do a direct comparison is welcome to come over and we'll rig a test apparatus. Nothing fancy or difficult, a free falling, weight from a fixed height, striking a test coupon. I have a round copper bar that'll make fine coupons and Starret instrumentation to measure.  

Anectodal testimony is like any opinion. Everybody has one and mine is the harder the anvil the more effectively it moves steel under a hammer and I've done this a while so it's not an unfounded opinion.

Frosty The Lucky.

 

[ThomasPowers]

I think the 3 main factors are: Mass, Hardness, and Rigidness of the mounting.    As a gedanken experiment consider those 3 factors with one of them reduced to zero while the others are left at "reasonable" levels.

So 3 cases: 

1)  Zero mass, reasonable hardness and reasonable mounting rigidity  What happens when you hit it?

2) Reasonable mass, zero hardness and reasonable mounting rigidity. What happens when you hit it?

3) Reasonable mass, reasonable hardness and zero mounting rigidity. What happens when you hit it?

[anvil]

l,don't know how to answer that, Thomas, with all due to respect. Zero mass? Reasonable mass?

How about this. The anvil face needs be tough, not brittle so it wont chip. The anvil face should be tempered hard enough to protect from dings made by missed hammer blows or especially those resting/thinking blows we all make music with. Thus, the anvil should be harder than your hammer. Thus my parameters for anvil hardness.

why? It's far easier to dress a hammer than an anvil. 

in other words, the primary reason for a hard face on an anvil is to minimize anvil wear.

As far as your cast iron anvil, well I rest my case and may it long remain where you tossed it. 

This post is about rebound for crying out loud. The only thing rebound indicates is to some degree, the level of hardness, eveness of temper, and any voids between face and body.

rebound has little to no effect on working your iron. 

and no, I've never had, nor wanted, and would have refused any cast aso. They are worthless in my opinion for just the reason you pointed out.

[localsmith]

It's mostly just personal preference. If you have a really hard anvil face than it's more liable to chip out if you miss which is the main reason why I don't like them along with the high pitched sound that they make.

[Frosty]

1 hour ago, anvil said:

in other words, the primary reason for a hard face on an anvil is to minimize anvil wear.

This is a conclusion, not an argument. Restating an unsupported conclusion doesn't back your personal opinion.

Thomas's use of linear extrapolation to extreme limits are to make you think about what you're saying. If you can't answer them then you haven't examined the original premise very well. He's only rebutting your unsupported premise that hardness doesn't matter compared to weight. 

Again you draw a conclusion that an anvil face is hard to minimize wear. This argument fails on it's face.  Even now, with modern manufacturing techniques, HC steel and the processes necessary to join it to a soft body cost many times what a cast iron anvil does. Even malleable iron. A person could afford to replace a cast iron anvil when it gets too worn. Or heck grind it flat again, it's just cast iron. 

If there were no performance differences sufficient to justify the cost difference we'd all be using cast iron anvils. Steel faces would never have developed beyond a couple failed ancient prototypes.

Localsmith: On what do you base your opinion? Just personal preference? How does that explain hardened steel faces on most anvils in countries that can afford them? More likely to chip an edge? You bet. Have you paid attention to anvil pics, how many top shelf brands have chipped edges? A new sharp file will skate on my anvil's face and it only has minor chipping on the edges from the 50+ years of professional use prior to me acquiring it.

Knocking chips out of an anvil's face is a result of missing. A sure sign of a lack of skill or indifference to the tool.  Torch cuts is a sure sign of indifference to tools.  Perhaps you're right though and shouldn't acquire a quality anvil until you've developed the skill to use one properly.

So far this is a friendly debate between KNOWLEDGEABLE friends; sort of like the one about "traditional" smithing. I'll bet Anvil sees more blacksmithing in a week than you have. I've been doing it a long time but don't come near his experience, and don't claim to. I'm just an effective researcher with a near eidetic memory for the written word and extraordinary reading comprehension. In this case regarding a craft I've loved since I was little. Right now we're mostly just smack talking a little, between friends.

Frosty The Lucky.

[anvil]

Ok, well lets start with Thomas's 3 points. Perhaps I'm too practical, don't know.

1)zero mass = nothing to hit, nothing happens. Yes?

2) zero hardness= it's going to distort, yes?

3)zero rigidity= all force is lost at the junction of anvil/stand, stand/ground= all force lost, yes?   

Thus my not understanding the analagy.

Frosty, my quote. Lil, out of context as I did to you a while ago, but I understand your meaning. Yes it is a conclusion, not an argument. Can you come up with a better conclusion or argument as to why this is not so for going to all the hassel of applying a hard face to any differing metalic body? I would imagine even modern cast steel anvils are heat treated to minimize wear on the working surface as a primary end results. Wear means preventing chipping if too hard to hammer dings or rolled edges if too soft and anything in-between. If either is the case, I suspect they would not sell many anvils. 

3 hours ago, Frosty said:

. A person could afford to replace a cast iron anvil when it gets too worn.

Well considering that a 100 year old PW is a young'n, and may or may not need to be refaced that's a pretty efficient process, then or now. And far easier and less expensive to reface a hammer than any anvil. That's a heck of a performance issue to justify the cost! And the only valid reason for a hard face on a piece of softer steel.

3 hours ago, Frosty said:

He's only rebutting your unsupported premise that hardness doesn't matter compared to weight. 

I'm sorry, but I can't find where I said this, nor even implied it. However, I'd have to agree with it.  I'd have to say that all things being equal between two anvils other than weight/mass, and both have an applied hard face, the faces would have the same heat treat. Basically hard enough to not be dinged by your hammer nor too hard that it easily chips. Same steel, same properties, same heat treat.

And a friendly debate it is between friends.

Respect to all.

 

 

[ThomasPowers]

I do a bit of research on medieval stuff and one thing I have learned is that a lot of times opinions stated as to why something is can be hilariously wrong; but the base idea quite right.   Often it takes modern science to explain the whys even if the basic belief is sound.  Example Malaria; was believed to be caused by bad air in swamps; so stay away from swamps!---Yup swamps are a cause; but it's because they breed mosquitos that spread the disease.  Conclusion is sound even if the rationale is not.

My take on this is that there is a minimum "allowable" hardness for an anvil face and that is harder than the steel being worked hot on it. I think we can all agree on that.  I believe that efficiency improves as hardness increase up until brittleness becomes a factor; this is also tied into how it will be used.  Thus an anvil for a bladesmith may work better with it's face harder than an anvil for a jackhammer bit repointer. 

Also the skill of the smith---I have a dead soft french pattern crosspeen that came from the Lynch Collection that I'll "suggest" to new students with hammer control issues; I tell them that it keeps me from yelling at them when they hit the anvil...  I also have anvils that suggest for people with more muscle than control---one is already missing the heel, another is an old oil field bridge anvil that was used as a "consumable" to repoint cable tool drill bits. (College students with sledges---scary!)

So perhaps there is a happy medium on anvil face hardness and what that is may vary amongst smiths and be correct for that smith in particular.

The anvil being the major tool of a smith is a prime candidate for smiths sitting around the woodstove talking together; just like Ford or Chevy, Blue or Red (Miller or Lincoln),  Pilsners or dopplebocks...  I'd mention one's children but it's obvious that mine are so superior to every other one in the world that it's not worth arguing over!

So I think I will mosey out back and see what I can find in the scrap pile and let this discussion go on without me.  My local scrapyard told me last visit they were thinking of moving the pile back away from the front of the lot.  Always interesting to see what was buried previously!  (Last time I found a mint condition stake plate, pexto 982 IIRC for less than US$9.  Also a bracelet mandrel. )  Weird what a small rural scrapyard may contain... Unfortunately I'm signed up for Covid testing tomorrow morning; I hope it goes fast so I can get to the scrapyard before it heats up too much.

 

[anvil]

Lol, it's always tough to post and run, especially with so much info you are putting in your last post. 

So, here's my response to those who may still be following this.

There's not much I agree with in your last post.

12 hours ago, ThomasPowers said:

harder than the steel being worked hot on it

Isn't the general rule, even for many of our contemporary tool steels to "get it hot". To me this is a light yellow. I see no reason for this to be a factor

 

12 hours ago, ThomasPowers said:

So perhaps there is a happy medium on anvil face hardness and what that is may vary amongst smiths and be correct for that smith in particular.

If true, certainly in your immense and enviable library you must have some advertisements or other data on anvils being sold with a particular hardness for a specific specialty or skill level?

I'll stick by a more practical conclusion and that is an anvil hard enough to not be dinged by a hammer, edges hard enough to not easily roll or mushroom, and soft enough to not chip the edges under normal usage. This is not hard to estimate. Hammers traditionally and good ones today are made from medium carbon steel and tempered to be tough, not hard. Thus a traditional standard followed to the day.

I've never had students abuse my equipment. I make sure they learn early just what is proper or not on my equipment. I do not allow for safety reasons as well as preservation of my equipment for 

12 hours ago, ThomasPowers said:

(College students with sledges---scary!)

To abuse my services or safety.

Before I give any student a double jack, or any hammer for that matter, I make sure they know exactly how I want them to hold it and how to swing it. How I have them hold it pretty well precludes them from wild hammer blows of any sort. It lends to controlled accurate blows that efficiently allow one to be able to swing that hammer for a full day if necessary and easily hit what they intend on hitting. This is just plane basic hammer safety.

Sorry to be so direct.

[basher]

well it is traditional to bed Sheffield cutlers anvils into their stone stands with horse droppings!

I personally am not at all bothered as to what the rebound of an anvil is like , I have never carried a ballbearing , and much prefer quieter ones to ringers. but each to their own.

 

[Frosty]

17 hours ago, anvil said:

Can you come up with a better conclusion or argument as to why this is not so for going to all the hassel of applying a hard face to any differing metalic body? I would imagine even modern cast steel anvils are heat treated to minimize wear on the working surface as a primary end results. Wear means preventing chipping if too hard to hammer dings or rolled edges if too soft and anything in-between. If either is the case, I suspect they would not sell many anvils. 

I don't have to come up with a conclusion, it's pretty well been established for a long LONG time. A hard face moves the WORK more effectively. That the tool is more durable is a side benefit, not primary. Of course HC faces are heat treated, hardened and tempered. You wouldn't sell a simple HC steel knife that had only been hardened would you?

For an argument besides my personal experience, I offer my student's choice of anvils in my shop. I have a 606 lb. Trenton in good condition and a 125 lb. Soderfors in excellent condition. Even after having the danger of missing blows on the edge it only takes a little hands on comparison before they'll wait to use the Soderfors rather than the vacant Trenton. Both are on near identical steel tripod stands and are pretty muted compared to spiked to a wood block. Either one will ring loud enough to make your ears ring through muffs and plugs. 

 

17 hours ago, anvil said:

I'm sorry, but I can't find where I said this, nor even implied it. However, I'd have to agree with it. 

You're right you didn't. Not in this post but weight over other properties is a preference I've come to expect. I shouldn't have mentioned it without you saying it. My bad, I retract the comment. 

It looks like a good thing I've been so slow writing a reply, it let Thomas post first. I have nothing significant to add unless I wished to dip further into semantics and semantic squabbles are almost always a sure sign that intelligent conversation has left the room. 

It's been fun, see you around.

Frosty The Lucky.

 

 

[arkie]

Here is an interesting experiment to try when forging.  Use your favorite hammer and forge a simple piece of say, 1/4" or 3/8" flat bar.  When forging wear as tight fitting ear protection as you can muster so as to have as little sound as possible to be heard...I mean close to zero.  Now pay close attention to the hammer and the sensation of the hammering.  It feels as if the hammer and steel are made of rubber and bounces back off the work piece.  The absence of sound produces a completely different sensory aspect to forging.

[anvil]

I'll give it a try. Lol, I think when I'm forging I'm lost in the moment. I hear nothing and hardly see anything. It's more a sending of what's happening to the iron. And all of a sudden days have gone by. And that's the time that makes it all worth it!

 

Frosty, again I have never in this thread, nor this website or with any group of people debated that one brand of anvil is superior to another, nor anvil pattern for that matter. I've worked on many different anvils in many shops and have never had a problem accomplishing my tasks on any of them. 

ive had one new anvil. It was an enders farriers pattern cast steel anvil. I used it daily for 17+ years 8-13 horses a day 6 days a week. I knew it pretty well you might say. When I went full time smithing I started with a 124# PW and stumbled across a 255# Trenton. The Trenton is to the day my daily driver. A lit of time on both. Here's what I noticed with my cast steel enders anvil. If you dropped your hammer on it, lol, I had no knowledge of a steel ball, it rang sweet, the rebound was incredible and it had an energy and life that couldn't be matched by my Trenton or PW. However, when I forged hot or cold iron on it,,, it acted no different than the other two. No magic, no myth, just a good solid anvil that moved iron like my trenton. What's this got to do with the price of tea in china? Don't know, it's my only long experience with a modern cast steel anvil. It had a place in my shop until someone walked off with it. Due to the fact horn, there were certain shapes that are much more difficult to get than with a blacksmith style horn. But it never forged my iron from the bottom side due to its superb rebound, nor did it return my hammer with any other magical force because it was a quality cast steel anvil with a very hard face, any better than my wrought/steel faced Trenton or PW.

[localsmith]

On 10/1/2020 at 9:50 PM, Frosty said:

Localsmith: On what do you base your opinion? Just personal preference? How does that explain hardened steel faces on most anvils in countries that can afford them? More likely to chip an edge? You bet. Have you paid attention to anvil pics, how many top shelf brands have chipped edges? A new sharp file will skate on my anvil's face and it only has minor chipping on the edges from the 50+ years of professional use prior to me acquiring it.

Knocking chips out of an anvil's face is a result of missing. A sure sign of a lack of skill or indifference to the tool.  Torch cuts is a sure sign of indifference to tools.  Perhaps you're right though and shouldn't acquire a quality anvil until you've developed the skill to use one properly.

So far this is a friendly debate between KNOWLEDGEABLE friends; sort of like the one about "traditional" smithing. I'll bet Anvil sees more blacksmithing in a week than you have. I've been doing it a long time but don't come near his experience, and don't claim to. I'm just an effective researcher with a near eidetic memory for the written word and extraordinary reading comprehension. In this case regarding a craft I've loved since I was little. Right now we're mostly just smack talking a little, between friends.

Frosty The Lucky.

More likely to chip if you miss is not really an opinion if you compare say, 52100 to 4140 or even mild steel. The lower the carbon content the tougher the steel and the less likely it will be to chip out if/when misses occur. Everyone misses once in a while which is why some of the best smiths anvils still have chips in them. Working with a striker can also result in misses that can chip an anvil. I'd rather deal with shallow dents than chips. I'm not 100% certain but I'm pretty sure that if we go back prior to the invention of the London pattern and German pattern anvils and their spin offs, most anvils that were used did not have a high carbon face. I care a lot more about anvil mass than rebound. I'd take a mild steel anvil that weighs 100# over a 20# high carbon steel stake anvil any day of the week. I don't think that rebound is pointless though, I just think that it's over rated and is a big reason why used anvil prices are so inflated. 

[Frosty]

16 hours ago, anvil said:

I think when I'm forging I'm lost in the moment.

You didn't really need to tell me that, I surmised it from many of your positions. You just make iron move, no need to analyze things you aren't doing at the time. Noodling on the internet with folk is when folk can spend the tie to think about these things. A professional has other things on his/er mind, thinking about this stuff would be a distraction, maybe a dangerous one.

I on the other hand am a hobbyist and was taught from a child to analyze the machinery and tools I was using so I could optimize them. No fooling Dad almost never showed me what the controls on a machine did, only the safety issues. Then he made me figure it out myself, think about putting a 9yro on a machine lathe with only a couple words of wisdom. Points at the jaws on the chuck and says, "If you touch those while it's running it'll mangle your hand." Pointing to the tool post, "do NOT run the tool or post into the chuck or it'll damage the machine."

He had me watch Mother run the circle shear for a little while then put me to work cutting blanks with, "You know not to couch the edges of the turning blanks, it'll cut you like a saw. The blanks go in that box, the scrap in that one." I think I was 8yro, it was the first machine I ran in the shop and forever my least favorite, it took forever to cut blanks. I was 9-10 when he taught me to run the punch press and he gave me some direct instruction on that one, they'll take a hand off faster than you'll feel it. I got to see the results of that, a spinner name of Johnny was punching blanks and tried to get a stuck blank out without shutting the press off. THAT was a hard rule. 

When I was 21 it took me about 1/2 hour to figure out how to operate a road grader, years to get good with one but the controls were easy. The drill rigs were a little harder, you couldn't follow linkage to the thing it worked, you had to slowly move the control and watch what moved and how.

So, yes analyzing how an anvil performs is my nature, I usually have a pretty solid working handle on how a tool or machine works before I try for speed. 

About not noticing the anvil returning the blow's energy from below. Does your work not flatten on the bottom side against the anvil? 

Frosty The Lucky.

[ThomasPowers]

"harder than the steel being worked hot on it"

"Isn't the general rule, even for many of our contemporary tool steels to "get it hot". To me this is a light yellow. I see no reason for this to be a factor"

I think we are miscommunicating here:  If the face is softer than the hot metal being pounded on it it embeds the harder material into the face. I learned about using that to put brass into silver back in the 1970's.  As having your workpiece not being embedded into the face of the anvil is a good thing; I think it is a factor.

I also think that there are multiple factors that make an anvil superior not just one.  I would prefer a 250# plain steel anvil to a 2.5 pound 52100 heat treated to HRC 60 anvil for ll save some jewelry work.

I will do a bit of checking to see if I find any references to anvil hardness in the old adds, they only ones that comes to mind are ones touting harder faces as being better---which seems to not support your position(s).