Sharpening a secondary bevel

[2ndunamended]

I'm just learning more about all the different grinds and bevels, etc... as I'd like to be more competent in sharpening my steel.

For example, the Mora Garberg has a Scandi grind with a secondary bevel. How do I learn to best sharpen such a blade? Am I just sharpening the secondary bevel? How careful must I be to make sure I'm not flattening it out? Any guidance on such sharpening basics will be much appreciated.

 

[Jason B.]

The secondary bevel is the cutting edge or edge bevel, it is the part that cuts.

With the blade you have the secondary bevel would be better called a microbevel. It should never exceed its micro status because it then becomes a bevel which offsets the primary bevel geometry. For a scandi grind this is vey important because the primary grind is typically the main focus of the sharpening. With thicker scandi knives like yours I would probably flat grind the primary bevel and keep it that way. It's a shallow scandi with a tall blade and thick stock, in my experience these usually hold a true flat ground primary bevel (true scandi grind) much better than their thinner stock counterparts.

I would flat grind the sides with a 1k waterstone then at just a slightly raised angle use a 6k or 8k stone to lightly polish the edge apex. You could call this a microbevel/secondary bevel but I would think of it more as grinding the edge of the scandi edge.

 

[2ndunamended]

The secondary bevel is the cutting edge or edge bevel, it is the part that cuts.

With the blade you have the secondary bevel would be better called a microbevel. It should never exceed its micro status because it then becomes a bevel which offsets the primary bevel geometry. For a scandi grind this is vey important because the primary grind is typically the main focus of the sharpening. With thicker scandi knives like yours I would probably flat grind the primary bevel and keep it that way. It's a shallow scandi with a tall blade and thick stock, in my experience these usually hold a true flat ground primary bevel (true scandi grind) much better than their thinner stock counterparts.

I would flat grind the sides with a 1k waterstone then at just a slightly raised angle use a 6k or 8k stone to lightly polish the edge apex. You could call this a microbevel/secondary bevel but I would think of it more as grinding the edge of the scandi edge.

Jason- thank you for this information. Much of it went over my head but I will catch on quickly. Thank you also for correctly identifying the secondary as a microbevel- this is indeed what I meant to say in my original post. I need to add some appropriate stones/sharpening apparatus to my bench.

 

[Tim the Wizard]

All that Jason said...

I would add that the best thing you can do is mark the edge with a sharpie and then freehand it so that you are only hitting the very apex of that sharpie. This may only be apparent under a 10x or 20x loupe.

 

[2ndunamended]

All that Jason said...

I would add that the best thing you can do is mark the edge with a sharpie and then freehand it so that you are only hitting the very apex of that sharpie. This may only be apparent under a 10x or 20x loupe.

Excellent suggestion. I will take a look at the edge of the Garberg before cutting with it to see how it comes from the factory. I know it will be sharp.

 

[Jason B.]

Typically, the factory mora edge is a machine ground bevel that has been buffed at the edge creating a "microbevel" of sorts. The primary grind will likely need some work as they are not dead flat from the factory, fyi.

To sharpen I would recommend waterstones, most will gravitate to the King brand and I would usually recommend them for scandi knives with carbon steel but that Swedish stainless is another story. Suehiro has some new combo stones in the US market of their Cerax line, they are the premium line from Suehiro and some very good stones. Do a little search, you can find a 280/1.5k and 1k/3k at CKTG. I would probably go with the 1k/3k and get yourself a lapping plate.