Ken's post made me think of this, Granton knives

[SharpenADullWitt]

The first image shows a knife in the jig. The Protrusion is 139mm, as I use with the kenjig.



Ken

The above image made me wonder if there are any issues to be aware of with knives that have the Granton edges.  (Santoku, Chef's, or Roast slicers typically) 
I realize these won't have the lifespan of those without, but am wondering how far down you can really go?  (my thoughts are when your at or into the Granton edges, the knife will have thinner and more prone to breaking the edge)

Thanks, rather learn before I screw one up.

[Ken S]

SADW,

I learned something from your post. I was unfamiliar with the term "Granton edges". I assume they are the indentations along the blade?

I would think the indentations would act like the scallops on a bread knife and be difficult to sharpen. The knife in the photo is a very recent purchase, an inexpensive knife bought for sharpening purposes. None of my older knives have the indentations. Do they lower friction between the knife and the material being cut?

Hopefully some of the knife specialists will post.

Ken

[SharpenADullWitt]

Yes they are the scallops, or indentations on the blades.  Their job is kind of an airgap, as the break the surface tension of the foods being cut (reduce friction) and don't allow things like Tomato's or moisture from food, to let the food stick to the knife. (why they tend to be only on certain knives)

[Herman Trivilino]

I would think the indentations would act like the scallops on a bread knife and be difficult to sharpen.

They do not act like the scallops in a bread knife. As you sharpen into them all they do is make the width of the bevel you grind narrower. The edge still remains straight. I haven't noticed that this has any effect on the knife's performance in the kitchen.

[SharpenADullWitt]

I would think the indentations would act like the scallops on a bread knife and be difficult to sharpen.

They do not act like the scallops in a bread knife. As you sharpen into them all they do is make the width of the bevel you grind narrower. The edge still remains straight. I haven't noticed that this has any effect on the knife's performance in the kitchen.

So do you find things like tomato slices, still stick to the knife as much as a normal, chef's knife?

[stevebot]

Grantons is the English name for kullenchefs (no sure of spelling), the vacuum breakers carved into the sides of the blade. Proper grantons are offset and ground about 40% through the blade. They do not affect blade life. You can keep sharpening right through them as long as you keep the edge centered. Poorly made grantons can pose a problem if they are over 50% deep.

[Ken S]

My inexpensive sharpening knife, as seen in the photo in this topic, seems to be a Granton style knife. I must try using it with food.

I had not heard of a Granton knife. Thanks for the education.

Ken

[SharpenADullWitt]

Granton is not the knife, that is a Santoku.  Kind of a Asian chopping knife.

[Rob]

I learn something new here every time I visit.

Granton.......sounds like a butler who might be working in Downton Abbey :-)

[Jan]

The Granton knife was patented in 1928 by William Grant & Sons Ltd of Sheffield, England. The Granton® is a Trademark of Granton Ragg Limited.

In the picture you can see the legendary original manufactured probably in 1930. The handle was made of ox bone and the knife measures 14 inches long and the blade is 9 inches.



In principle the Granton edge is today available on any knife, but is most popular on ham, beef and salmon slicer knives.

Jan

P.S.: William Grant & Sons UK is a leader in the UK spirits industry, I think it is the same family. I know a little bit Glenfiddich, the single malt Scotch whisky and the tripled distilled Tullamore D.E.W. Irish whiskey. Both are excellent. 

[Ken S]

Another most interesting post, Jan. History has been a life long interest with me, and I find your posts intriguing.

Keep up the good work.

Ken

[SharpenADullWitt]

Jan, that photograph, would have answered my questions right off the bat.  I have never seen one where the edge is in those bits, but always below them by a tiny bit.

[Ken S]

This topic is an example of topics I increasingly appreciate, topics pertaining to the Tormek, but which also include interesting peripheral information.

I enjoy the extra depth we get from replies from many members. I always thirst for knowledge.

Ken

[Jan]

Jan, that photograph, would have answered my questions right off the bat.  I have never seen one where the edge is in those bits, but always below them by a tiny bit.

SADW, you are correct, the majority of granton knives have the scallops above the cutting edge.   

In my thinking it may be technologically easier, you do not have to worry so much about the depth of the scallops and their pattern.

As mentioned by Steve, when the edge goes through the scallops their depth should by less than some 40% of the blade thickness and also higher quality steel is required because the scallops are weakening the blade significantly.   

Jan