forging stick tang from 1 1/2" stock

[kbaknife]

I stand behind everything that Ed does.
He is one of the major factors in my 5160 success.

[Jeremy]

I haven't been taught by any of the master smiths, nor stood over their forge watching.  But I do know people who's livelihood is in the proper heat treatment of steel (and other metals) where the tolerances are literally a matter of life and death.  

To say that working metal hot results is unrepairable grain growth is in direct contradiction to everything learned in the science of metallurgy in the last 50+ years (and I'm only counting that far back b/c that's the earliest X-ray diffraction data I'm aware of).

There are dangers to working steel too cold, and I haven't seen those mentioned here yet.  There are three temperatures to be concerned about.  The first, Ac1, is "the point at which the shift from alpha iron to gamma iron first begins." Uh, simply means the ability of carbon to move around in the steel increases, but there still isn't enough heat to break the heavier carbide bonds.  If you hang around this temperature for too long, either by forging at too low of a heat or taking too long to reach non-magnetic (which the the second temp to be concerned about Ac2) you get carbon segregation and banding in the steel.  The worse this problem becomes, the longer you need to hold the steel at the third temperature (Ac3 or Acm) to properly normalize the steel.

[kbaknife]

Strange how this thread has evolved.
The knife world is a big place, and it is occupied by lots of people, makers, enthusiasts, etc.
It's the people we choose to travel our chosen paths with that make the entire adventure worthwhile.
The knives, and how they are created, are almost secondary.
Not quite - but almost.
More like hand-in-hand.
Without the other, neither one has any value.

[chris amos]

As Karl pointed out this could go on forever. The proof is in the pudding. If you are a knifemaker testing your knives and getting good results then whatever you are doing is working, go with it! As far as the big words, again, I don't know about that. I do know that while banding is bad in industry because of the variety of ways a part will be stressed due to machining, temerature, pressure, etc, it is a good thing, and a goal, in the type of knives I make. Great care is taken to promote banding in the grain of the steel from tang to tip. It adds strengh and toughness, much like the grain in wood.

[chris amos]

To back up a little bit, I would be very interested to learn more about the knives that "Lamey" talked about forging at a yellow heat. That seems a little to hot to me and I know you said that in your post. What is the reasoning, beyond the ease of forging? What steel are you using and how do you treat it, hardening and tempering wise? If your getting good results that is very interesting to me. Well done. How are you testing your finished knives?

[Lamey]

Chris,  most of what I forge is W2 or 1095.  In the case of W2,  I start with round bar varying from 1.5" to 2" round, with the 1095 its 3/8" thick.   In my view you have less of a chance to induce stress/ harm to the steel by forging the upper end of the limit.  You will spend less time in the heat, fewer cycles for the same amount of movement.  

There is nothing "harmed" or lost when forging at higher temps, im not keeping the steel at those temps for extended periods of time, and use proper "cycle down" heats toward the end.  Ive been to industrial forge operations and they forge on the upper side as well, and are making very critical parts.

After the "cycle down"  (dropping the forging temp the last few passes that im basically just getting everything "straight"),  i do a fairly standard 3 tier normalization process.  

I bring my blades up slowly to 1500 and quinch in Texaco "Tuff" quinch warmed to 120+/-.  Depending on the blade and its intended use I will do at least a double temper, sometimes tirple, again depending on the blade and its use.


Ive done alot of testing, chopping both green and dry bamboo (no shortage of that in my yard),  rope testing (on the table, using multiple cuts checking abrasion resistance),  all kinds of chopping in the woods as well.  Also done ALOT of flex testing in the vice (testing flex vs bend on varying differentially hardened blades, finding that perfect "blend" of having enough hard steel not to take a "set").

Ive got over 1000 blades out there,  with many hundreds actually being used hard,  get lots of feedback from my customers which helps me in my work greatly.  

I take great pride in my work,  and will put my blades with any made for toughness, performance, ergonomics etc...

Heres a 10" chopper blade pic was forged from 1.5" W2 round bar (started as a 3.5" piece, the blade was 10" x 2" with a 4.5" tang)-

 

[Jeremy]

Originally posted by chris amos:
Great care is taken to promote banding in the grain of the steel from

Chris,
It's been a while since I've visited Ed's site, but the banding you and he are talking about is the micro banding that runs parallel to the edge, right?  That's still an even distribution.

Take a blade and do half a dozen or so cycles at just below non-magnetic.  What you'll end up with is not the even micro banding; it's fairly large and random swirls and bands visible with the naked eye.  You're right, "great care" must be taken to get the fine structure and distribution you're going for.

Forging too much at too low of a temperature causes problems that DO need to be corrected by a longer soak time to normalize... which is beyond the capabilities of most here who do not have proper temperature controls on their forge.  It's very easy for beginning smiths, or for most hobby smiths, to fall into the trap of working the blade when it's too cold.

IMO, it's easier to forge at a higher temperature and then correct any grain growth with proper reducing heats after forging.  That's managable by most smiths and results in a fine grain with even particle distributions.  I don't see that result as evidence of "unrepairable grain growth" (though I must admit to getting a smile knowing I made Ed laugh with my comment       )

[Lin Rhea]

Chris and Karl, it sounds like you both very much have your methods down and although have both atended Mr Fowler's workshop have taken slightly different philosphies away from it. That's the way I see it, as different philosophies. Both of your methods work for the type of knife you want to build and for the performance you want to see.

Whereas most, especially budding knife makers, are happy with just making a knife that will cut and somewhat hold an edge along with looking decent, you both have taken your work to a different level by tailoring your methods with a particular performance in mind. That's not a bad thing. It shows a lot of experience and testing has gone into it.

Getting it HOT is relative. The only way to know just how hot is to describe it in degrees, but as a rule, the more mass in a piece of steel, the more heat you need to be able to move it with the same size hammer. Then reduce the heat as the material gets thinner or in smaller cross sections.

Matt said something interesting about bend and flex which goes along with what I try to acheive in my knives. Like him, I want my blades to flex as far as possible without taking set.

Lin

[Lamey]

I also want to add that I do what works for me,  It may not work for some one else.  Im not saying its the "only" way,  but for me it works the best.  Ive blended a bit from different makers, different books, and 15+ years of being a fanatic about forging, heat treating and good cutting knives.

Was  also fortunate enough to "refine" and put some important "touches" on my skills with the best person ive ever seen with a hammer, or blade,  Jimmy Fikes.   If any of the old timers here were fortunate enough to see him in action years ago at some of the Hammer Ins (He was a major influence in starting Ashoken) you will know what im talking about.

[Lin Rhea]

I added an important picture that helps me explain how I start the tang back at the beginning of the thread. Page 1
            Lin

[Lamey]

great pics Lin,   do you ever "set" your choil,  then pull your edge down from the "set"?

[chris amos]

Thats a great looking blade Lamey, nice job! Its good to hear you are into serious testing. Sounds like you have what works for you worked out. About the banding, perfectly even grain isn't what I am looking for when I etch a blade. A blade with the uneven, swirls and grain pattern will, in my destructive testing, always be stronger. Think of it like cement. A cement slab for a building or other heavy use is mixed with aggregate of all sizes from sand to gravel to large rock, maybe 1 1/2 inches in diameter. These variations in size distrubute the stress's over a larger area and interlock to create a stronger structure. A cement with a small aggregate only like sand will go down smoothly and look great, like plaster. But it doesn't have any strength. You can break an inch thick piece of plaster with your hands. The "rules" used in industry are for making money. They are the largest margins for error allowable to achieve an exceptable product. Each formula and pour I am sure is different, some are certainly more exacting than others depending of the purpose of the steel. The margins that I use, and that work for me, and are specialized for my purpose. my desires for the steel and the industry standards are not the same thing. That's ok, just like all you guys have said, you have found what works for you and we are all looking for a way to make our knives better. That's what it's all about.

[Lin Rhea]

Matt,
 I think I know what you mean. I usually do it just like the photo shows, but I never say never. I forge my main stock slightly larger than my finish ricasso size and pull everything from that outward, only having to resquare the ricasso some. If the blade is a particularly wide one, I may have to start with wider stock, pull down the choil, then reduce the ricasso upward, the net effect dropping the choil even more. Sometimes I will start with the tang just to see if I can forge it backwards. Aint knife makers crazy? Lin