Tormek Jig positioning for a chef's knife

[AusSn]

I remain fairly unclear on where the optimal KJ-45 jig positioning is for a standard chef's knife type blade.  In one of the early live classes on YouTube Wolfgang positions it parallel to the straight part of the blade and in a more recent Kitchen Knives edition he says to draw a line from the heel to the tip.

I have to admit I have tended to orient it parallel to the initial straight portion.  Is there a consensus on this point?

[tgbto]

With time, I realized I tend to clamp parallel to the flat, with the side of the jig shaft (the pivot point), roughly at the point where the belly of the knife is. So I'd say a mix of both pictures...

I find this allows for both minimal effort when grinding the flat of the blade, and best control along the curved part and in the tip area.

[RickKrung]

With time, I realized I tend to clamp parallel to the flat, with the side of the jig shaft (the pivot point), roughly at the point where the belly of the knife is. So I'd say a mix of both pictures...

I find this allows for both minimal effort when grinding the flat of the blade, and best control along the curved part and in the tip area.

There was a discussion of this back in mid-2017 where a template was presented that helped in setting this position.  Images I saved back then are below.  I can't remember what if was called, so haven't found the discussion.    It may have have had to do with lifting vs pivoting.  Anyone recall it and maybe point us to the thread?

I use this template to this day for setting up knives. 

Rick

[RickKrung]

Found it!  Had the time frame a bit wrong, but I worked back from 2017.

Knife Point Setting Template, by Jan
Started by Jan, October 27, 2015, 10:49:00 AM

[Ken S]

One of my regrets with this forum is that our newer members never had the opportunity of working with some of our outstanding, now deceased members. Jan (Jan Scanvara) was outstanding. He was a combination of a practical, helpful, down to earth member and a highly educated, innovative professor of engineering from the Czech Republic. He was also a good friend.

Ken

[Ringarn67]

This is a really good discussion on this forum
Knife tip grinding - To Pivot or Not To Pivot

[tgbto]

This is a really good discussion on this forum
Knife tip grinding - To Pivot or Not To Pivot

Indeed it is.  And as mentioned in countless other threads, there is no unique answer to "where to clamp the knife" or "how should I pivot" / "how should I lift". For a given blade geometry, how you should lift/pivot will depend both on where you clamp and how you want the edge to be (constant bevel width ? constant bevel angle ?). Change something, the rest will have to change.

The Tormek rule of "lifting only, no pivoting" is safe enough for common kitchen knives clamped in the way Wolfgang demonstrates in its basic classes, for knives where the edge angle usually gets a bit higher at the tip. It is however an oversimplification, as examplified by the fact that Wolfgang pivots in his videos. The matter is also evoked in the advanced knife sharpening video.

[3D Anvil]

I generally prefer to clamp parallel to the straight section of a chef's knife.  That way, the majority of the blade will be at the desired angle, and the belly/tip will get a higher angle which tends to keep the bevel width more uniform and adds more edge stability where it's most needed.