Restaurant commercial knives

[Jan]

Jan,
My English is at it is and I can easy missunderstand things I read....

But you wrote that "we can never duplikate existing edges". My sharpening tool EdgePal Chef can duplicate edges exactly. With exactly I ment down to 1/100 part of 1 degree.

To do this is a matter of how fine you can adjust a sharpening tool. The pivot point on my tool Chef are mounted kn a bar. The height of this bar is asjusted by two special nuts that clamp the bar between them. The nuts can be adjusted be oss they can be screwed (?) along a M4 standing screw. 1 full turn of the nuts change the edge angle with 7/100 parts of 1 degree. That means that 1/7 of a full turn change the edge angle with 1/100 part of 1 degree.

The nuts I talk about above have markings on them, a small black dot. Withbthe help of this dot you can se how much the nut is turned - and in this way you can asjust the edge angle very fine.



This picture shows two knifes. The upper knife have three differetn bevels, 9, 10, and 11 degrees. The 10 degree bevel is not polished, I have left it raw.

The other knife have 5 different bevels. They are about 1 mm wide, there is 0.75 degrees between them and they are straight from the handle and belly out to the tip.

With my tool Chef can I go from bevel to bevel and hit the bevel 100 % correct by using the black dot on the clamping nuts I talk about above.
* Notice, this is a standard function on my sharpening tool Chef.

Chef also sharpen both flat and convex edges in wanted degrees - and convex edges can be made in wanted convex sphere in degrees. This means that if you like ro have a convex edge with 3 degrees convex sphere and 26 degree total cutting edge - you adjust for this on Chef - and you will get it on the edge.
That is also a standard function on my tool Chef.

If you like to meaasure how many degrees an edge holds you can meassure this with Chef. Just lay the knife on the grinding tables magnets, adjust the distance 28 cm between the edge and the pivot point (with the help of markings on the guide rod). Use a whiteboard pen and draw a line across the edge. Lay down the sharpener on this line, adjust the bar untill the sharpener take away the whitboard pen line - and read on the built in protractor the  degrees on this edge. Very simple to do.

A thing that can be nice to know when adjusting like this. A whiteboard pen leaves  2/100 part of 1 mm thick ink on the edge.
A permanent ink line is 1/100 prart of 1 mm thick.
When I make multipel bevels on a edge I use permanent ink

Thomas

Thomas, your English is fine, my is secondary language also.

My statement "strictly speaking we can never exactly duplicate an existing edge" was not about edge angles, but about the fact that each sharpening removes some blade material and makes the edge thickness larger, because it widens towards the spine. After many sharpening this increase may be so large that the knife does not perform well. Victorinox recommends to keep the edge thickness between 0.4 to 0.6 mm. Panta rhei (Heraclitus), "everything flows".

I know quite well your sharpening tool EdgePal Chef because it is on my wish list, but thanks for your additional explanations. I know that the angle setting accuracy is far beyond the needs of a standard knife sharpener. You claim that the accuracy can be 1/100 part of 1 degree. I am wondering if you can guarantee this accuracy along the whole edge – from the heel to the tip.

The upper Mora knife on your picture probably does not have a consistent bevel angle along the whole edge. Changes in the height of the edge on your knives indicate possible significant change in the bevel angle. The lower knife seems to be OK.

   

Your mechanical protractor is surely good for measuring bevel angles, but cannot measure a microbevel with a height of 0.1 mm (100 microns). Even for my laser angle master it is a very challenging task. Unfortunately such a microbevels are typical e.g. for new Morakniv knives.

   

Jan