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View Full Version : Question for Larrin - Casting a Blade



ajhuff
04-24-2013, 11:49 AM
This is strictly a curiosity question.

I was daydreaming this morning and wondering about casting a blade. I would think maybe in a graphite mold against a chill plate to give a carbidic edge and a ductile spine. Yield would be horrendous. I think a subsequent rolling would be necessary to close internal porosity. Certainly not a practical or feasible method forming a knife. But has anyone done it for kicks?

Thanks,

-AJ

Pensacola Tiger
04-24-2013, 11:54 AM
David Boye has been casting dendritic steel and dendritic cobalt blades for over thirty years. I have one of his folding dendritic cobalt boat knives and it is a great EDC.

http://boyeknives.com

ajhuff
04-24-2013, 12:10 PM
David Boye has been casting dendritic steel and dendritic cobalt blades for over thirty years. I have one of his folding dendritic cobalt boat knives and it is a great EDC.

http://boyeknives.com

I don't see anything there that implies the blade is cast.

-AJ

Pensacola Tiger
04-24-2013, 12:21 PM
I don't see anything there that implies the blade is cast.

-AJ

Gee, I gotta do searches for you guys, too? :eyebrow:

http://www.francineetchedknives.com/about_page.php?id=24

ajhuff
04-24-2013, 12:53 PM
Gee, I gotta do searches for you guys, too? :eyebrow:

http://www.francineetchedknives.com/about_page.php?id=24

Still nothing that says the blade is cast. I'm talking about a blade cast to near net shape.


-AJ

zitangy
04-24-2013, 12:55 PM
hey thanks . this is new to me.. interesting read.....

Zwiefel
04-24-2013, 01:12 PM
David Boye has been casting dendritic steel and dendritic cobalt blades for over thirty years. I have one of his folding dendritic cobalt boat knives and it is a great EDC.

http://boyeknives.com

From the above link:
"Not a steel, it is a mixture of cobalt, chrome, nickel, tungsten, silicon, iron, and carbon."

:scratchhead: It's got Iron + Carbon...what else is needed to call it steel? :dontknow:

Pensacola Tiger
04-24-2013, 01:12 PM
Still nothing that says the blade is cast. I'm talking about a blade cast to near net shape.


-AJ

I guess I just don't understand what you're asking. What is "near net shape"?

Boye's blades are cast. From the second link:

"Dendritic Steel is a term first used by knifemaker David Boye to describe the cast 440c stainless steel he developed in 1981. This revolutionary blade technology has proven superior to most other cutlery alloys in both edge holding capability and ease of sharpening. The process used to produce it, investment casting, transforms the original steel into one infused with microscopic crystals which create tiny serrations along the blade edge. These micro-serrations enable the blade to stay sharp from 10 to 50 times longer than a conventional blade. It also has a better "bite" (the ability to grip and cut into slippery objects --a tomato, for example) than conventional steel blades. It cuts like a razor blade by microscopically sawing the object, thereby achieving a finer and faster cut."

Here's a pic of the cast dendritic cobalt blade:

http://i758.photobucket.com/albums/xx226/Pensacola_Tiger/Misc%20Photos/file_zps732a8faf.jpg

ajhuff
04-24-2013, 01:15 PM
From the above link:
"Not a steel, it is a mixture of cobalt, chrome, nickel, tungsten, silicon, iron, and carbon."

:scratchhead: It's got Iron + Carbon...what else is needed to call it steel? :dontknow:

The iron component is to low to be considered a steel.

Zwiefel
04-24-2013, 01:16 PM
PT, I think the OP is saying that just because the material is created by casting doesn't imply that the blade is cast... i.e. "forged" vs "stock removal"...

ajhuff
04-24-2013, 01:18 PM
I guess I just don't understand what you're asking. What is "near net shape"?

Boye's blades are cast. From the second link:

"Dendritic Steel is a term first used by knifemaker David Boye to describe the cast 440c stainless steel he developed in 1981. This revolutionary blade technology has proven superior to most other cutlery alloys in both edge holding capability and ease of sharpening. The process used to produce it, investment casting, transforms the original steel into one infused with microscopic crystals which create tiny serrations along the blade edge. These micro-serrations enable the blade to stay sharp from 10 to 50 times longer than a conventional blade. It also has a better "bite" (the ability to grip and cut into slippery objects --a tomato, for example) than conventional steel blades. It cuts like a razor blade by microscopically sawing the object, thereby achieving a finer and faster cut."

Here's a pic of the cast dendritic cobalt blade:

http://i758.photobucket.com/albums/xx226/Pensacola_Tiger/Misc%20Photos/file_zps732a8faf.jpg

I see that the material is investment cast. It doesn't say the blade is. For all I know he's casting bars and slicing them into knife blanks. And we won't even get into the "discovery of dendritic steel" mumbo jumbo.

-AJ

Pensacola Tiger
04-24-2013, 01:21 PM
PT, I think the OP is saying that just because the material is created by casting doesn't imply that the blade is cast... i.e. "forged" vs "stock removal"...

From what I can tell from the one I have, the blade is cast, then a bevel is ground. I think the pic I posted pretty much shows that if you look at his maker's mark.

I could be totally wrong, of course.

ajhuff
04-24-2013, 01:28 PM
Cool! Thanks!

-AJ

Reede
04-24-2013, 03:04 PM
There was a bit of buzz probably 8-10 years ago on Blade Forums about a product called Liquid Metal and the possibility of casting finished size blades. It disappeared from mention fairly quickly. I remember the general thought being that it would probably only apply to mass production knives, because the mold making process was pretty expensive. I am assuming that since we haven't heard about it in a long time, that the stuff didn't end up being advantageous to use for knife blades.

Here's a link:
http://www.bladeforums.com/forums/showthread.php/676856-Liquidmetal-knives

Zwiefel
04-24-2013, 03:40 PM
From this link: http://boyeknives.com/
"Not a steel, it is a mixture of cobalt, chrome, nickel, tungsten, silicon, iron, and carbon."

:scratchhead: It's got Iron + Carbon...what else is needed to call it steel? :dontknow:

WildBoar
04-24-2013, 04:29 PM
"...The process used to produce it, investment casting, transforms the original steel into one infused with microscopic crystals which create tiny serrations along the blade edge. These micro-serrations enable the blade to stay sharp from 10 to 50 times longer than a conventional blade. It also has a better "bite" (the ability to grip and cut into slippery objects --a tomato, for example) than conventional steel blades. It cuts like a razor blade by microscopically sawing the object, thereby achieving a finer and faster cut."
They took what would be considered a negative related to the casting process and present it as a net positive. So is it more like a gyuto that has been finished on a 1000 grit stone for some 'toothiness', or more like a Cutco?

TB_London
04-24-2013, 06:06 PM
Stuart Ackerman (formerly Zackerty) also does cast blades in, I think 440c. Really nice knives take a ferocious toothy edge, hence the name Serrata. AFAIK he's doing a colab with spyderco which is currently underway

ajhuff
04-24-2013, 07:54 PM
Thanks TB, that helped a lot. I was able to find this:
http://knifedogs.com/showthread.php?30190-Making-the-Serrata

It's a different approach than what I was envisioning but pretty slick. He's getting a much better yield than I would have thought. Very interesting.

-AJ

Larrin
04-24-2013, 08:48 PM
Since my name is on the thread I'll just say I have nothing to say.

wenus2
04-24-2013, 08:53 PM
Since my name is on the thread I'll just say I have nothing to say.

Your mother taught you well. :thumbsup:

ajhuff
04-24-2013, 09:16 PM
Since my name is on the thread I'll just say I have nothing to say.

Why not? I value your input.

-AJ

Larrin
04-24-2013, 09:48 PM
All of the examples I know of were already brought up, and I know little about casting.

ajhuff
04-24-2013, 10:04 PM
Gotcha. Thanks!

-AJ

TB_London
04-25-2013, 04:13 AM
Thanks TB, that helped a lot. I was able to find this:
http://knifedogs.com/showthread.php?30190-Making-the-Serrata

It's a different approach than what I was envisioning but pretty slick. He's getting a much better yield than I would have thought. Very interesting.

-AJ

Ah I was digging around for that thread but couldn't find it as was on a different forum. A metallurgist over here put some samples from one under a Scanning Micrograph but the images seem to be dead now plus it's written in badger speak

http://www.britishblades.com/forums/showthread.php?63569-CSI-Serrata-The-Trial-Continues

LeifAnders
11-15-2014, 06:53 PM
As I mentioned in my first newbie post I made knives and also sold knifemaking materials to other knifemakers here in northern Europe. Then I also imported and sold the David Boye folding knives with cast blades and also his line of cast blades for knifemakers and among them there was his cast 440C blades. I still have three of the blades in my stash from the 90:s, se image. There one can see the traces from the casting process. The cut off channels for the steel to flow through, the tang with the Boye name and the casted overall finish.

I sold a bunch of blades to knifemaking customers, but I don't know if they turned into finished knives. I also made two finished knives (one with the 175mm blade and one with the 210 mm blade) that I sold to two chefs in Stockholm. I also got a few requests from other chefs for knives, but then I had quit my knifemaking.

Apart for the chefs blades I have also included one images on a David Boye made folder and one on a skinner that I made made with a blade from David Boye. They are from the 90s and I still have them around.

http://3.bp.blogspot.com/-YofdXdKIFeI/VGfUTcvaSpI/AAAAAAAAIH8/GJHBT066gEI/s1600/David-Boye-Cast-Dendritic-440C-Chefs-Blades.jpg

http://1.bp.blogspot.com/-ekkWkfLuD0Q/U_nuaHGHsAI/AAAAAAAAHgk/a6XeP7K_mNI/s1600/David-Boye-folder-denditric.jpg

http://3.bp.blogspot.com/-e1HpFyqpKrs/U_2plkENzOI/AAAAAAAAHi8/JGf3ra-p-tQ/s1600/LAB-Skinner-BoyeBlad-a.jpg

ecchef
11-15-2014, 10:34 PM
One thread I'm glad was resurrected. Those cast blades look mighty interesting.