Drill it out or scrap it?

[JimCrawford]

Ok. Do stress fractures come in groups, or can you just have one?

I've got a blade with some cracks that appear localized, and I was considering drilling them out in a decorative manner. Should the crack be considered a harbinger of a larger flaw in the steel, and the blade pounded out to scrap or practice metal?

Thanks!

[oakwoodforge]

Jim, I tend to file those in the " learning pile " , is this a problem with a particular batch of steel or is this a heat treating / forging issue ?

[JimCrawford]

A good question. I'm inclined to think that the forging errors are mine. One set of the cracks, a little spider web, corresponds to an area that wasn't completely heated when I quenched the steel. The other crack is a mystery.

Thanks for the thoughts!

[ThomasPowers]

Generally if something went wrong, it went wrong. Especially if you don't know why I would not use it---However I do turn some of my "oops" into shop knives or for my personal use with the caveat that if it self destructs it's on my own head.

[HWooldridge]

Cracks can start propagating from scratches that occur due to grinding - either before or after quench. They act as a stress riser and the amount of stress in a hardened blade can be significant. Not annealing between forging and hardening processes can also cause cracks.

[JimCrawford]

H,
I think the amount of stress in a new knifemaker/blacksmith can be pretty significant, too. I'm beginning to think that God is telling me to be patient.

-J

[Nick]

The crack can and probably does go further than you can see. I'd chalk it up to experience and try again. It's a pain, but it's part of the proccess, too.

[julian]

Jim you could also bend test/break the blade in half to see how your heat treat is doing. Whenever I mess up on a knife blade I usually experiment with it to see how well it cuts or holds up under stress.

[V]

Re heat and re shape?