to grind or not

[dancho]

I am absolutely sure that forging skills is much more important than any device including grinder.  If one is approaching blade SMITHING   why not to learn it.  

 

It is possible to forge  almost perfect shape  with no grinding at all which needs only  minor hand shaperning on a water stone to start  cutting.   Time needed to do this is almost the same as with grinding.  

 

However the advantages are:

1.  You save every bit of steel wich makes sence if you are using very valuable steel (like refined steel that I prepare and use myself)

2.  Properties of the forged blade are usually better due to directing the metal texture  according to the function. Of course if forging and heat treatment is done properly

 

 

But polished surface of a knife still  better for cutting  (and more hygienic).  To get it I use a set of high quality  files.   They work amazingly quick if you anneal the blade properly  and  are VERY precise.  And silent . And safe.  And you can do it anywhere even without electircity. 

 

One of the most important tricks is to harden already sharpened and polished blade.

[Rich Hale]

Dancho, Maybe you can help me with a couple of things in your post:

In forging a blade to direct the metal texture, That seems like the fad that is still used by some called edge packing...And we know that goes away int eh heat treating steps...Is it the same or if nor how is it different?

You like to heat treat a blade that is already polished and sharpened, Woot do youi do about the layer of decarb that forms during that process. All of my Stainless blades can be done that way as the heat treater uses an atmospheric contolled furnace that leaves no scale on blades. I use a scale preventing product on my carbon steel blades I do in my shop and still have a little clean up to do after HT. I always leave about a pennies thickness along blade edge until HT is done the do final finish, To me it seems if I have sharpened and then have to repeat after heat treat it just adds to amount of work.

 

Thoughts?

[basher]

I am absolutely sure that forging skills is much more important than any device including grinder. If one is approaching blade SMITHING why not to learn it.

It is possible to forge almost perfect shape with no grinding at all which needs only minor hand shaperning on a water stone to start cutting. Time needed to do this is almost the same as with grinding.

However the advantages are:
1. You save every bit of steel wich makes sence if you are using very valuable steel (like refined steel that I prepare and use myself)
2. Properties of the forged blade are usually better due to directing the metal texture according to the function. Of course if forging and heat treatment is done properly


But polished surface of a knife still better for cutting (and more hygienic). To get it I use a set of high quality files. They work amazingly quick if you anneal the blade properly and are VERY precise. And silent . And safe. And you can do it anywhere even without electircity.

One of the most important tricks is to harden already sharpened and polished blade.hamon

I wish that were true in my world ......where steel is cheap and I am not.

Because I am committed to the path of pattern welding most of my blades and or differentialy heat treating the monosteel blades. I need to remove completely all decarb and oxidised material in order to see the patterning of the pattern weld or hamon n the steel. This requires grinding and always has by hand or machine.

The sad truth (if you find it sad) is that when it comes to making knives, you can achieve more in a given time with a good grinder and a 36 grit belt than you can with a hammer.
Power hammeers change this of course.....they lessen your forge time so that you spend less time forging compared to the grinding (sob sob).....

now, I forge everything I make and am in love with the forging .....however I have a well established relationship of respect with my grinders and get great satisfaction from being able to use them well and artistically.

My observation of historic pieces along the ages is that it has always been thus, people have always wanted shiny and to the larger extent that is what people have made.

I love axes so much because I can let the forged material remain forged (unless I make them in damascus!!).

Forging is good, grinding is also good and change the balance and feel of a tool to an extent of subtlety that forging alone finds hard to reach.

Both are just tools to get you where you want as a craftsman.

I have tied myself into an industrial version of bladesmithing and I can be incredibly productive because of the mechanisation at my fingertips.

There are however many roads to a Blade.

[dancho]

Dancho, Maybe you can help me with a couple of things in your post:

In forging a blade to direct the metal texture, That seems like the fad that is still used by some called edge packing...And we know that goes away int eh heat treating steps...Is it the same or if nor how is it different?

You like to heat treat a blade that is already polished and sharpened, Woot do youi do about the layer of decarb that forms during that process. All of my Stainless blades can be done that way as the heat treater uses an atmospheric contolled furnace that leaves no scale on blades. I use a scale preventing product on my carbon steel blades I do in my shop and still have a little clean up to do after HT. I always leave about a pennies thickness along blade edge until HT is done the do final finish, To me it seems if I have sharpened and then have to repeat after heat treat it just adds to amount of work.

 

Thoughts?

 

Hello Rich! I am here to help!

 

1.  The metal texture is not a fad but   something known very well in physical metallurgy science at least here in former Soviet Union .  It is not about the edge packing ( which is probably a fad ) neither cold-hardening neither anything about grain.

Any metal (apart from very pure forms unavailable for most mere mortal smiths) has non metallic impurities  (NMI) as result of the process of making.   Some more some less it depends on the quality and variety of specific alloy. Initially they are formed between the dendritic crystalls then drawn into long texture  as ingots rolled into bars or whatever.  They are with us forever no matter we want or not.  When you forge  you  move and guide them.   When you grind, turn or mill you cut them.   The forging process has ability to redistribute the NMI in the volume of the work piece according to the direction of stresses applied to the piece or its function in general.  That’s why critical  details in mechanical engineering  (bolts for instance) are formed  by pressure not cutting.  That’s why forged to the minimum edge usually has better cutting properties  (given proper heat tretment )  . We turn the enemies (NMI) into our friends. 

 

1. If you work with a char coal forge with side blast and properly keep the  air volume,  the distance and mass of coal between tyere and piece virtually no decarbonisation happens.  Quite opposite  you can get carbonisation if you intend to.   It was tested many times both by me and  many others beginning from my teacher V. I. Basov in the 70-s
2. Of course we remove the scale  at least on the edge if we are sharpenning it in my case by a file and with stone.    Scale is better removed since it it creates  cohesion with the piece we are cutting.  No matter how I like the forged surface it is not good on the knife unless the people specially ask me to leave it.

 

1. I do not work with stainless steel mostly because I do not enjoy  the process of forging it into edges. Carbon and iron are good  hearty boys.  I like communicating with them.  Chromium  is a strange man after 10 percent. For me at least.
2. Hardenning of already sharpened edge gives you the opportunity to heat only the edge stip and get diffrential hardenning (something like hamon ).   The process of heating takes seconds.  The scale simply doesn’t have time to form.  Again it is best done with the char coal side blast forge.  Tempering is also differential
3. Sharpening of  already sharpened blade after hardening and tempering is extremely quick.  Few strokes on a water stone and done.

[Rich Hale]

Dancho I will stay on the other side of this fence,,glad it is working well for you.

I have always believed that in the heat treat process including normalizing and hardening,,and maybe a little bit in the trmpering side. All things done to the steel during forgingtime are changed. Whether you have forged and maybe align particles or have sheared them of them with a grinder, The heat puts them back to a standard structure. And this is why I brought up edge packing..it to me is the same thing.

And you mentioned bolts The good ones for sure are forged  and no doubt adds strength in the end...However they are not then put through the heat treat process to completion or any benefits from the forging would be lost.

Thanks so much for sharing your thoughts,,,,

[dancho]

Dancho I will stay on the other side of this fence,,glad it is working well for you.

I have always believed that in the heat treat process including normalizing and hardening,,and maybe a little bit in the trmpering side. All things done to the steel during forgingtime are changed. Whether you have forged and maybe align particles or have sheared them of them with a grinder, The heat puts them back to a standard structure. And this is why I brought up edge packing..it to me is the same thing.

And you mentioned bolts The good ones for sure are forged  and no doubt adds strength in the end...However they are not then put through the heat treat process to completion or any benefits from the forging would be lost.

Thanks so much for sharing your thoughts,,,,

 

Thank you too! I enjoy the discussion.

It has worked not only for me but for the centuries of smiths before.  It is really amazing  how we came to forgett the things obvious for any illiterate smith in some ukrainian village a hundred years ago as well as to his illiterate customer  came for a knife.

 

As I said the texture is not about grains and nothing happens to it during heat treament.   It is only forging that changes the orientation of the particles.  All what I am talking about is found in any book on metallurgy.   The texture of the metall tested by X-raying and  I believe it is  done at  many factories.

[Frosty]

Dancho: Do you have any empirical evidence for your claims? Centuries ago what you say was true, impurities were of significant proportions, modern steels hold so few impurities as to be insignificant.

 

If forging produced significantly stronger products you'd see forging as the main commercial method. You see forged bolt heads, engine crankshafts and such, not because they're stronger but because the process is faster and cheaper.

 

Heating to critical causes crystallization, how much is time dependent but impurities migrate as part of the process. Steel wouldn't harden except for work hardening if this type of crystallization didn't occur. Forging can crush the crystal boundries commonly called grain structure as that's how excessive crystallization appears in breaks, as grains. Forge refinement works on steels held at high heat for long periods. Tempering serves to break crystal boundries while allowing carbon to assume less strained positions in the steel, edge bonded as opposed to face bonded. This makes for tougher products by a controlled softening of the steel. Heat treating removes most grain manipulation by forging processes.

 

Steel does NOT by definition have a grain in any way similar to wood, this is a hold over from wrought iron days and has no value to modern materials or work.

 

Texture for instance isn't discussed at all in any book on metallurgy I've ever seen, not one. Title, author ISBN # please. The only discussions I've ever encountered regarding texture is only in the finish, say I want my piece finished with a bark or scale finish. Decorative textures in other words. Not meaningful metallurgy, Decorative.

 

My opinion comes from a life spent working with metal, simple to high end aerospace alloys, on my own and in my Father's shop. Dad couldn't afford myths, they cause excess work and time is money in a professional shop. Some of Father's work has left the solar system.

 

If you have empirical evidence, please post the raw data and cite your references. My opinions are subject to change, it just takes REAL evidence, not another's opinions. I've been through this forged is better than machined discussion too many times and have never once seen evidence, let alone proof of the opinion. It's been my experience that ALL evidence of significant grain structure in "steel" is centuries old and refers to "steels" made from puddled wrought iron, not modern manufactured steel.

 

If you're going to educate us, bring out the proof sir.

 

 

Frosty The Lucky.

[dancho]

Gentlemen!
I suggest that we move discussion on the texture, grain, NMI or whatever of this kind into separate topic and continue there. I will put there information I have on the subject and ready to change my opinion and learn from others with low profile. I am defintely not an expert in metallurgy. I admit that my claims on this specific subject were too quick and not carefull. Excuse me.

Same for the heat treatment and decarbonisation though here I feel more confident. Separate topics.

However the main point of my initial message was to not about mettallurgy. The question was

but to help "Shape" the blade what are you folks using?? It will be awesome for the wood on the handles, but I need to find something to help my bad forging

My points are:

• We can do pretty well by SHAPING the blades by forging alone and do not need a grinder not to mention any space technologies. The grinder is not a replacement for forging skills though they are not quick to learn. Forging blades to final shape is quick and efficient at least with carbon steels. We do not need to make simple and energy efficient things that already work more complicated and energy consuming as well as to omitt the art of forging for the benefit of mythical “productivity” unless going to deprive Chinese folks of their jobs. :)
• After you have forged the blade you can refine the outline, get the surface plane and sharpen the blade by a FILE. Files are great qick, precise tool largely omitted now.

Apart from these advantages they do not consume the electricity (thus adding pollution to the environment), silent, safe and can be recycled after use into the next blades which corresponds to the modern principle of sustainable production called “from cradle to cradle”.

I am qiute sure that my smithing qualification, skills and experince are adequate to support these claims.
I put it it here since feel responsible to give the younger brothers who enter the world of smithing the complete picture. It is up to them whether they use the information.

I would like to take my time now to respond to Owen Bush meessage which contains very important points needed a discussion and this goes beyond the problem of grinding. It is about basic values of our art andor craft. Maybe a separate topic is needed again.

Thank you!

Bogdan Popov

 

The topics have been split as per request

[Rich Hale]

Actually your interest in helping "the younger brother" is why I posted to begin with. This site has an unbelievable number of viewers daily. And when I saw your post about metal texture etc that was so against the ways I have learned I had to ask. it concerned me that our new folks in the bladesmithing world were again being exposed to data not supported examination using modern methods. i mentioned the edge packing similarity and I stand by that.

No matter wot you do to HC steel with a hammer, the internal structures change when it is heated to critical temperatures. And for me that is a good thing as stresses are relieved if done correctly.

Dancho we totally agree on forging skills. If someone wants to forge anything they should learn to do it correctly. And the same holds true for all aspects of in this case bladesmithing. They should know wot to do after the metal work is done. And how to make the rest of the knife. And for some of us the finishing touches to showcase the knive is the leather work.

And no I just do not lurk around here and wait to pounce upon anyone that seems to me to be off track in these areas. Steve Sells and I offered knife making lessons on this site to demonstrate the steps and offer text and pictures to give folks a starting point,,and to go beyond that. In fact we offered information that would take a new person with limited skills and equipment a way to work steel in a step by step approach that in some cases actually led to completed knives. ir you are interested all of our lessons are in the knife forums.

[Rich Hale]

For my own interest I have studied metals and how to heat treat them in a couple of manners. I read everything i can, and am sad that I have never studied enough. There is always something else on the matter. For shop testing I have limited my testing to steels I am about to use or have used For HC steels that short list, not counting the stainless steels I regularly use. Is 0 1,1084,1095, L 6 15 N 20 and a couple of mystery steels like vehicle springs and files. I showed how I test those steels in shop to see if they are suitable for knives and to determine heat treat methods. I posted those methods in the blade making lessons in the forums also. My shop testing is fundemental basics. In no way do I feel I can define a method by these tests..However when supported by data availeable these days quite easily via the internet I am comfortable that knives from my shop. And information I post on here is current and correct. I depend a lot on information in the heat treat stickies on this site. I say this as the " younger brothers" may wish to dig into this subject more at depth than we are covering in this thread.

In reallity I believe you and I have a lot in common. I think we see a lot of things in the same light. I also think we share an interst in helping new folks get started and move into bladesmithing.,I also believe I will stick with my thoughts on wot steel does when we heat to critical temps after forging or stock removal.

[basher]

I am interested to hear what you have to say Bogdan.

 whilst i have a firm certainty about how "I" approach the craft I am also aware that it is not a singular road but more of a merging flow of paths that sometimes meet and often are quite divergent .

[Frosty]

I'm thinking I came on a little strongly and wish I hadn't. I'm afraid I'm getting crankier in my dottage, I've been reading too many opinions on the web written by kids who's sum total of smithing knowledge is gained by playing role playing games, not fire, anvil and hammer.

 

I'll gladly read any cites Bogdan, you live in a different world from me and I'm into learning anything available. So please continue though I see no reason to place your evidence, cites, proofs, etc. in another thread. They do after all bear on this thread.

 

So, please carry on friend.

 

Frosty The Lucky.

 

For those that joined late, this thread was split off 28 March 2013, from the other thread, due to that topic having little if anything to do with this topic.   It happens often in the forum, threads evolve, so we split them apart when we see a need for easier location later when people wish to find this information.

[itsme]

Frosty, your clarity is appreciated

[John McPherson]

Frosty, I have to politely disagree: rolled plate from a modern strip mill does indeed possess a directional grain structure, with different strengths measurable in the X, Y and Z axis. It forms during the initial casting and is refined during the hot rolling process. The grains lengthen along with the shape being rolled, whether that ends up as a plate, tube or I beam.

 

Textbook cites if you so desire, but I am a Certified Welding Inspector and Instructor who has bent a lot of welder test plates in the past 5 years. Failures of test samples due to plates cut on the wrong axis are easily identifiable.

 

In earlier times, forging was as much to minimize loss of an expensive material, as the lack of other methods to form a strong blade. Today, proper reforging of a billet of steel into a blade shape will produce a better, stronger finished product than stock removal of a billet cut along the wrong axis, all other things being equal. 

[Rich Hale]

John thanks for your note,,,,does that directional difference in strength,,supported by testing,,,remain after the normalizing, hardening and tempering cycles used in high carbon steels?

[Frosty]

John: Please do either post the cites here or shoot them to me on the side. I spent a goodly part of my professional career as a certified welder and fabricator before taking up with the state of AK.

 

I don't follow the current state of the art (iron/steel) so all I really have is old memory and experience to speak of. Every single example of "directional grain" I've been shown as proof have been mill defects, typically edge shuts where the surface has moved under the rolls producing a visual effect similar to wood grain.

 

Then, by time a person buys a piece of steel at the supplier, be it bar, strip or plate it's been roll forged to a fare the well. A 20'  stick of 1/2" rd. was sheared from what, a mile or two of 1/2" rd.? Starts in the pig mold or continuous caster as what 5 tons per ingot to be rolled, non-stop, to the finished dimension? Sure, plate, especially say 3" thick spends a lot less time under the rolls but what are a bunch of guys with hammers going to do to effect it's structure?

 

To clarify my position, I'm not referring to milli-micron structure. I refer to grain or impurities of significant levels to be modifiable by human hand power. Not happening in a competently run modern steel mill.

 

Of course that's just my opinion, I could be wrong.

 

Frosty The Lucky.

[Dodge]

Frosty, I have to agree with John on the grain structure present in rolled steel. Where I worked (traffic lighting and control standards and power transmission structures manufacture) we had to be aware of this grain to the point, when a piece was cut from a coil, the grain direction had to be marked (and remarked each time it was cut smaller) so that if it was used in a part that required a bend line, that bend could be oriented across the grain so there was less chance of it cracking along the grain (seen it often in miss-marked steel). If a brake press operator ran across a piece that the previous operator neglected to mark, it was either scrapped or used as material for parts that required no bends.

 

Rich, to my knowledge, this grain direction would indeed disappear during forging, normalizing and heat treat.

 

Sorry, I don't have cites to post; just speaking from 25 years of hands on experience.

[Frosty]

I'll concede to the experience of you guys, my experience is certainly not greater than yours, we must have worked different fields of a similar craft.

 

Frosty The Lucky.

[basher]

I was hoping that this thread would become a soulful discussion of the merits of forge finishing or grinding (or parts thereof) from a technical , aesthetic , historical and personal point of view.

 I will be hitting the forge making axes over this next week, two dane axes which are almost completely forge finished (apart from the ground cutting edges) and two 300 layer damascus ones which will have to be completely ground clean through the Decarb and into good steel.

 I am exited about the forging as big axes are an exercise in moving metal around the houses .

 I am exited about the damascus ones as I love damascus. I will find a decent new album to listen too to see me through the grinding!! 

 I find it very very easy to get lost in the process and I value the way the process often shows in the finished piece.........I think that at least some of my clients also feel that way.

[Richard Furrer]

Bogdan,

I am curios about this statement of yours:

"If you work with a char coal forge with side blast and properly keep the  air volume,  the distance and mass of coal between tyere and piece virtually no decarbonisation happens.  Quite opposite  you can get carbonisation if you intend to.   It was tested many times both by me and  many others beginning from my teacher V. I. Basov in the 70-s"

 

I agree that a properly tended fire can maintain the steel more or less as it was made as far as chemistry, but I think it a rare smith who can do this all day. A fire can remove or add carbon as well.

I would guess that unless a smith is wishing to have a certain atmosphere in the fire then that atmosphere will change during the forging.

 

Not much information from your part of the world has made it to the US....I would like this to change.

 

Keep posting please.

Ric