Forged or stock removal Let's dispell the myths

Keith Montgomery said:
So as not to send this thread of on another tangent, I now return you to your regularly scheduled program.
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Sorry, as I did risk taking us off course of this thread, however just wanted to drive home your earlier point as to the forging "tradition" and mine regarding the influence of early americans on today's forgers.

As we all know how many, what type, who used James Black's knives and his connection to Jim Bowie varies as to which historian's account you want to believe.

But if for no other reason, the number of great forgers from the same region as James Black's shop demonstrates his influence.

Perhaps another thread to debate this history would be interesting.
 
I know some makers that use dies to forge in the hollows instead of grinding them in. They do this on pattern welded as well as homogenous steel.
 
jdm61 said:
Are you SURE? Let's get some input from smiths who forge their own damascus. The most extreme argument made agasinst stock removal is that you "cut across the natural grain pattern". Maybe the most extreme argument against forging is that all of this talk about grain, etc, is malarky and that by forging, you. as a rank amateur in the field of metallurgy, mess up steel that was produced to be as good as possible for it's intended purpose. Makes for a fun time on the forums, don't it?
:) Personally, i like the process of forging. I really dig what i can do with a hammer. I hate grinding becuase that is where 90% of my screw ups happen. But that's just me.
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There is no such thing as "natural grain pattern". That's one of the forging myths that needs to be dispelled. There's two things I know of that people see and say "grain pattern" or "grain flow". One is alloy banding, the other is the pattern that the impurities in the steel make when you etch a blade. Neither of those have anything to do with the grain.
 
Phillip Patton said:
There is no such thing as "natural grain pattern". That's one of the forging myths that needs to be dispelled. There's two things I know of that people see and say "grain pattern" or "grain flow". One is alloy banding, the other is the pattern that the impurities in the steel make when you etch a blade. Neither of those have anything to do with the grain.
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Yep, carbide and impurity follows the grain of rolling, so do the grains, but they recrystallize in normalizing or annealing. If you buy low impurity steel it doesn't matter, and carbon steels carbides dissolve during forging (or rolling by the manufacturer), so it's not an issue in carbon steels, only high alloy (air hardneing tool steels), or stainless steels.
 
I collect forged and stock removal knives. With today’s steels and heat-treating methods, IMHO there is no significant performance difference except (maybe) for very big blades that benefit from differential heat treat with a springy spine.
As someone mentioned, almost any steel is forged to a reasonable size (including PM steels, those powders don't weld in neat rectangular shapes ;))
The performance, fit, finish and the visual appeal of the design are the things I look for, not the method used to make the knife.
Now that I think about it, most of my folders are stock removal (CNC included) and most fixed blades are forged.
 
flava said:
I collect forged and stock removal knives. With today’s steels and heat-treating methods, IMHO there is no significant performance difference except (maybe) for very big blades that benefit from differential heat treat with a springy spine.
As someone mentioned, almost any steel is forged to a reasonable size (including PM steels, those powders don't weld in neat rectangular shapes ;))
The performance, fit, finish and the visual appeal of the design are the things I look for, not the method used to make the knife.
Now that I think about it, most of my folders are stock removal (CNC included) and most fixed blades are forged.
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And you can do a differential heat treat as a stock removal maker anyway.
 
Larrin said:
And you can do a differential heat treat as a stock removal maker anyway.
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For the modern steels you need a very precise heat treat to get the best out of it. Most stock removal makers use the services of professional heat treaters, so the blades are fully quenched and tempered.
I'm curious though how the stainless and semi-stainless steels (154CM, S30V, D2, BG42) respond to differential heat-treat!
 
flava said:
For the modern steels you need a very precise heat treat to get the best out of it. Most stock removal makers use the services of professional heat treaters, so the blades are fully quenched and tempered.
I'm curious though how the stainless and semi-stainless steels (154CM, S30V, D2, BG42) respond to differential heat-treat!
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Because they air harden you would have a difficult time differentially heat treating stainless steels. It is possible, but not commonly done because of the difficulty. I'd rather do a three layer laminate, but oh wait, that isn't commonly done either; oh well, if I can do it, I'm not worried about anybody else.
 
Phillip Patton said:
There is no such thing as "natural grain pattern". That's one of the forging myths that needs to be dispelled. There's two things I know of that people see and say "grain pattern" or "grain flow". One is alloy banding, the other is the pattern that the impurities in the steel make when you etch a blade. Neither of those have anything to do with the grain.
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hence my comment about the primary arguments. But if their is no "grain pattern" then why is a forged crankshaft considered to be better?
;)
 
jdm61 said:
But if their is no "grain pattern" then why is a forged crankshaft considered to be better?
;)
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Because the impurities will weaken the steel, if the strain is applied the wrong way.
Still has nothing to do with grains of steel...
 
jdm61 said:
the CPM steels are a curious lot. Is the chemical mix of the steel really all that "modern" or just the method of getting it into a usable bar form?
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The process isn't powder sintering, that much I know, though the details are lost to my memory. The chemical mix of the steels in many cases (CPM S90v/420v for instance) would basically crumble the moment you looked at them were they produced using "standard" melt techniques.
 
yoda4561 said:
The process isn't powder sintering, that much I know, though the details are lost to my memory. The chemical mix of the steels in many cases (CPM S90v/420v for instance) would basically crumble the moment you looked at them were they produced using "standard" melt techniques.
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I think it's called "nitrogen gas atomized" or something like that, anway, it's much better than sintering.
 
Larrin said:
Because the alternative is cast.
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Is it not possible to CNC machine a crankshaft?

I know it would be prohibitively expensive, but is it not something that COULD be done?

This is simply for my own edification, and not an attempt to derail the discussion.

Best Regards,

STeven Garsson
 
Larrin said:
Not to mention most forgers actually grind their blades after making the damascus so not to ruin the pattern.
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Well, I did say above that it DEPENDS on the pattern!
If it was random or twist, it GAINS in character from forging. Now, to do stock removal on Jerry Rados Turkish Twist would be a disaster! Especially if it was to be done to the profile. For the most part, Jerry hardly even sells his Twist as bar only. He will forge the shape to the pattern of the blade for the customer so all rows of the Twists follow the profile of the blade and they all end up at the point!
That pattern of Damascus MUST! be forged to profile shape. Take a look at the Blade Magazine December 2006 page 32 of the Ken Onion kniffe with Jerry Rados Turkish Twist. If this thing had been ground to shape out of a bar, it would have been a disaster. Note how the rows of twist follow the shape of the blade.
Like in the Siska Fighter with jerry's Twist, it MUST be forged for the Pattern to follow the profile of the balde. This is NOT! ruining the pattern, it is utilizing the patter to its utmost!
(Note how that bottom row of twist follows the edge of the blade all the way around from the guard, down the ricasso edge, along the cutting edge all the way to the point - as does the top row!)
image20-20031204.jpg
 
But after forging it to shape, are they grinding it, or forging it? I'm just saying, to say that grinding damascus is an insult those that forge it isn't correct. And though there are often times that the forgers will forge their damascus to shape, not all of them do, but yes, it can depend on the pattern, I know all about patterns. I don't think using turkish twist that was not forged to shape would be a disaster.
 
jdm61 said:
interesting, but to my point, they say that they "press" the particles at forging temp, not melting temp. Sounds like a form of sintering or "welding" to me
;)
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The difference is in the terminology and the process.
 
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