Stunning wootz Kard

Richard Furrer · 13th February 2013, 12:43 AM

Quote:

Originally Posted by Chris Evans

Richard,

Does not seem as if the edge has been quench hardened. So how hard do you estimate it to be?

Cheers
Chris

Impossible to tell without measuring on a machine.
As an indication of variety I suggest these two videos taken in Jodhpur, India. The two doing the testing are from The Wallace Collection of London and I'm the bearded one standing behind them.
http://www.youtube.com/watch?v=xyGXTlEAaAY
http://www.youtube.com/watch?v=vMwZWp0b5kE

Generally speaking the matrix (dark areas)will deform before a chip forms...this is the nature of pearlite, but when you quench and turn the pearlite to martensite and do not reheat enough to temper that hardness then chips are more likely. The white bands are cementite and largely unchanged from heat treatment...they are very hard indeed...harder than martensite.

I have held some blades that, after testing, I was very careful setting the blade down...they were so hard I have no idea how they lasted hundreds of years. I would have thought a wing of a butterfly would shatter the edge.
Much to learn.

Ric

Chris Evans · 13th February 2013, 01:41 AM

Richard,

Thanks for those links and your explanation.

Cheers
Chris

CharlesS · 13th February 2013, 02:22 AM

The original quality of the entire piece is superb.

The koftgari work is exceptional.

The blade's finish and edge, would likely benefit from a professional polish.

Battara · 13th February 2013, 03:22 AM

Charles is completely right.

We both know of a great polisher for the blade. And I too LOVE the koftgari - great and precise workmanship!

TimW · 13th February 2013, 08:27 AM

The good thing about wootz is its combination of a softer matrix (that can be hardened into martensite after quench) and the carbide strands. Even unhardened these strands will cut like hell...

Doing a rockwell C measurement on the blade is feasable (i have a rockwel C tester in the workshop, but am not too eager to start pitting this knife), but hardness will greatly vary between the 2 structures of the steel. I've worked with recent wootz blades that have been / have not been hardened - both do the job.

As for the polish: the finish as seen is just a quick plunge in ferrochloride just after I received the piece. I'll give it more attention / decent polish in the near future. I was allready very surprised seeing the actual patterns, even with this no nonsense etch.

As for the grind: I have the feeling that someone gave it a well executed regrind. The grind itself is well executed; if this knife deserves / needs this grind is another question. Based on the chipping of the edge I would think that someone asked for a regrind of the blade (to make it a better cutting tool), that this regrind has been done 'professionally', but that this regrind was too thin for the actual steel (thus the chipping of the blade). The grind is doen before the chipping. the kard with its original 'fatter' grind would (imho) not have had the chipping problem.

Tim

13th February 2013, 08:27 AM	#5
TimW Member Join Date: Aug 2010 Posts: 54	The good thing about wootz is its combination of a softer matrix (that can be hardened into martensite after quench) and the carbide strands. Even unhardened these strands will cut like hell... Doing a rockwell C measurement on the blade is feasable (i have a rockwel C tester in the workshop, but am not too eager to start pitting this knife), but hardness will greatly vary between the 2 structures of the steel. I've worked with recent wootz blades that have been / have not been hardened - both do the job. As for the polish: the finish as seen is just a quick plunge in ferrochloride just after I received the piece. I'll give it more attention / decent polish in the near future. I was allready very surprised seeing the actual patterns, even with this no nonsense etch. As for the grind: I have the feeling that someone gave it a well executed regrind. The grind itself is well executed; if this knife deserves / needs this grind is another question. Based on the chipping of the edge I would think that someone asked for a regrind of the blade (to make it a better cutting tool), that this regrind has been done 'professionally', but that this regrind was too thin for the actual steel (thus the chipping of the blade). The grind is doen before the chipping. the kard with its original 'fatter' grind would (imho) not have had the chipping problem. Tim Last edited by TimW; 13th February 2013 at 08:37 AM.

13th February 2013, 01:41 AM	#2
Chris Evans Member Join Date: Mar 2005 Location: Australia Posts: 685	Richard, Thanks for those links and your explanation. Cheers Chris

13th February 2013, 02:22 AM	#3
CharlesS Member Join Date: Dec 2004 Location: Greenville, NC Posts: 1,854	The original quality of the entire piece is superb. The koftgari work is exceptional. The blade's finish and edge, would likely benefit from a professional polish.

13th February 2013, 03:22 AM	#4
Battara EAAF Staff Join Date: Dec 2004 Location: Louisville, KY Posts: 7,280	Charles is completely right. We both know of a great polisher for the blade. And I too LOVE the koftgari - great and precise workmanship!