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Main Boards => Hunting Knives and Crafters => Topic started by: Doug Campbell on March 26, 2010, 09:17:00 PM
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or "only strike while the iron is hot"... Lots of those old sayings are also sage advice if we're smart enough to follow them... :readit:
Oh and your welcome ;)
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Man, that just kills me.
But you are so right, Doug.
There are some laws in 'smithing that just can't be broken, or you will pay the price.
But that is one of the best sayings going - strike while the iron is hot.
You can sort of LIGHTLY tap your steel into dark temp submission, but hit it too hard in the lower temps and you'll just induce micro-fractures.
Probably one of the reasons for many of the performance test failures!?! The inexperienced smith just forged too cool.
That is some darned nice looking grain, however.
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thanks for posting this.
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Doug , i am no expert and a slow learner. i am just not good enough to have 2 going at the same time especially at certain stages. i just burned a railroad spike last week. it that why smith's swear ???
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Doug, I hate it for you, but it's good to show stuff like this.
Here is what I think happened, which totally aggrees with Karl's and your opinion. When you hammered the sides of the edge, as you mentioned, a little too cold, the micro cracks started. Then when you quenched they just did what was natural and lead the cracks on into and through the blade. They were still so small that the oxidation pretty well hid them from view.
Assuming that all is well, you finished out the blade and just got around to seeing them as you were looking for scratches.
I have done this too so I know the routine. But, it all started with hammering too cold.
Thanks for letting us all see. It will help those who take it to heart. Lin
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another thing to consider is anytime you forge anything with a "corner", in this case square stock (4 corners), either grind or forge the "edges" into bevels. If you start forging with a square that has "sharp" or very distinct edges you can create stress on that edge that you cant see until later.
THe few times I forge square bar I first forge it into almost an "octagon", so to speak, then forge my blade.
Was taught this by a wise but grumpy old timer.
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Great info...thanks
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That's good advice, Matt.
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Absolutely right Matt, having worked in the steel fabrication industry in one form or another for pushing 25 years stress risers should always be one of our concerns. I'll typically "round" up square corners just for that reason.
After further thinking on this blank a little more I think I did another no-no which would have been just fine without the cold forging. I remember that the forged blank just barely fit my pattern of the blade I was looking to make. I probably didn't have and 1/8" of extra metal along the edge... Any tiny imperfection I'd forged in along the edges would have been left in the finished blade...
Along these lines of thinking do you other forgers leave "extra" sacrificial metal to grind away to the final dimensions?
Yep, there's always room to learn... ;)
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Originally posted by Doug Campbell:
Along these lines of thinking do you other forgers leave "extra" sacrificial metal to grind away to the final dimensions?
Yep, there's always room to learn... ;)
Yes, I do, but not much. Maybe .050 - .075". I continually make 1/8" patterns of my blades to forge "to" when making a blade. If I come up with a new profile, I make a pattern right then and there for later if I'm required to make another one.
As I finish up a blade I tweak it pretty darned close to the pattern I'm using.
I don't leave much on the profile, but some. A fair amount on the thickness as well.
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I try to forge as close as possible, more for "fun" than anything else.
I dont use a pattern so its not as critical for me, although ive really been thinking about making up some templates so I can get my sheaths done in "batches"!
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To offset this, I just make my patterns a little large all the way around including the length. Then I just grind till I think it looks right barely inside the pattern edges. If the finished blade is supposed to be 9 inches, my pattern is 9 1/4 inch or so. Lin
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Doug,
If I didn't know better, I would have thought those were the hands of a florist :biglaugh:
Interesting...
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quote:
Originally posted by Steve O:
Doug,
If I didn't know better, I would have thought those were the hands of a florist :knothead: <><
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Darn it mate... I sure hope my little one is more lucky when being put together!
Thanks for the tip!
ak.
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Good thing you found them before you sent that knife off to its future owner. Much better to break it now than later. Thanks for sharing this info with us Doug.