This should make you think......

[kbaknife]

I did this one this week.
No clay.
The only thing that influenced this hamon is steel type, blade geometry, heat, time and quench.
I applied no media of influence on this blade.
I post this here to give fruit to your thinking process when considering what's going on in your blade during the hardening process.
It's a simple W1 Brute de Forge with a mortised tang.
But, I hope you do appreciate the natural hamon.
Comments? Questions?

 


 


 

[Arrowest]

So Karl, does this indicate any problems or concerns for the integrity of the blade steel? If not, what does it indicate?  I understand the creation of a hamon when using clay but find this quite intriguing and I'm not really grasping what's going on. Education time, please.

[kbaknife]

There's nothing wrong with the steel at all.
It's all quite good.
The clay on a fully austenized blade insulates the steel underneath from the quench oil, which quickly drops the steel temp from around 1500 to well below about 900 degrees in only a matter of a second or two.
If the steel was allowed to drop through that window of temperature slowly, the steel would use that time to revert to pearlite - the condition the steel was in BEFORE you brought it up to austenite.
The clay creates a barrier between the steel and the quenchant, which keeps the oil from cooling the steel off in those few precious milli-seconds, and allows the steel to begin its reversion to pearlite.
Once it starts, it's hard to stop.
Of course, the shallower hardening the steel, the lower alloy of the steel, the faster this all takes place.
Well, simply THICKNESS of steel will do it as well.
Look at the spine - there's hamon there as well.
There's so much heat in the thicker areas that the oil can not get the heat out fast enough to stop the reversion to pearlite - the soft stuff where the steel would rather be.
Notice here how the "tiger stripe" hamon even sort of radiates from the cutting edge in a radial pattern.
This is following the thickness/cross section away from the cutting edge.
I admit, I can not in any way describe why the steel chose to follow this stripe pattern. I am completely perplexed by that.
I wish I knew more.

[daniel boon]

Karl, looks good and seems to match on either side.  

[kbaknife]

Certainly- the hamon on blades is not just on the surface, it goes all the way through.


 

Originally posted by daniel boon:
Karl, looks good and seems to match on either side.      

[Suty]

Karl...... Very nice, I can't wait to see mine up here      Does W1 have better rust protection than other carbons ? Thanks , Sutty

[kbaknife]

Ken, no, it doesn't.
Considering that even "stainless" will rust, if it's not designated as stainless, it will need your attention.
Just like any firearm, a little maintenance will go a long way.

 

Originally posted by Suty:
Karl...... Very nice, I can't wait to see mine up here         Does W1 have better rust protection than other carbons ? Thanks , Sutty

[Suty]

Karl, I Completely understand, and in no way would I not perform my knife maintenance .... Thanks Buddy,  Ken

[kbaknife]

What gets delivered:

 

[Fallguy]

Don't worry fella's it well be getting regular maintenance and attention. I am one luck fellow. Thanks Karl.

[Steve Nuckels]

Karl, Just wondering, did you quench the knife vertical or horizonaly?  I would think if it was quenched horizonal the vapor jacket may influence the Hamon....!

However it happened it looks cool and the knife is great looking!

Steve
--------
Potomac Forge
W.F. Moran Jr. Museum & Foundation

[Fallguy]

Karl I just scrolled to the top to droll a little more. I see where you a little blood along with the sweat in this project.

[bjansen]

Karl,  would you mind describing the process you use to bring that hamon out....is it a ferric chloride etch first, then metal polish?

[akaboomer]

Very nice Karl. I love how the hamon developed on the spine. I understand the theory of how and why but haven't attemped it. Did you do an interrupted quench?  What type of quench oil?

Thanks for sharing it here and for answering questions.

Chris

[BowHuntingFool]

Very nice!

[kbaknife]

I don't have a lot of time here tonight, but I'll do a quick answer on the questions above:
Yep - my blood. And in fact that's a good example of why simple carbon steels can continue to cut AFTER they go dull. That knife wasn't even sharpened yet. But it still cut me.

Steve, it was a horizontal quench in a three foot long tank. I go in at one end and go back and forth along the length of the tank. Parks 50 does not have much of a vapor jacket, and what there is, is nearly irrelevant because I'm constantly on the move.

Chris - Parks 50, un-interupted.


Brad, I used to just live east on 24 almost to Indiana in Watseka. I finish the blade to 1200 grit. Etch 30 seconds 4 or 5 times, cleaning off the oxides in between with 0000 steel wool. Do a final cleaning with Mother's mag wheel cleaner.

[bjansen]

Thanks Karl.  Yes I remember you used to live in Watseka and were in the UBI.  But the UBI banquets that you attended... I did not and vice versa thus never had a chance to meet you.  Very much appreciate the hamon process overview.

[Fallguy]

I just received my knife from Karl and it is FANTASTIC!!!! It is one very comfortable knife in the hand and easy on the eye as well. The only down side is its 4 1/2 months till hunting season. I may have to grill a big thick steak just so I can get a little blood on it sooner.    THANKS KARL

[kbaknife]

Glad it made it safely!!
Be careful - it's sharp.

[amar911]

I really like that knife, Karl.

Allan