Another Bevel Angle Question

[pitted_soul]

All,

I hadn't given much thought to setting new angles on a primary bevels, most of mine are pretty thin BTE, but is 15 degrees where it should stop as a good angle without compromising too much? This would be on the paper steels and, say, 52100. Could lower angles like 10 degrees be ok, say on a protoypical Yoshikane 240 or an Eddworks? Without sacrificing edge retention too much?

I need to get better at sharpening overall, but I was curious where the limits were, and what the rule of thumb is, when it comes to primary bevel angles. I am not looking to get the sharpest angle ever but wanted some thoughts on how do discern which angle is right for a given blade where an ideal balance of retention and performance is achieved (theoretically).

 

[tostadas]

15 is conservative. I don't take detailed measurements of my angles anymore, but I'd guess that I typically sharpen somewhere around 10-12deg. I feel like the thickness matters more than the angle at the edge as it relates to strength of the edge.

 

[pitted_soul]

So, a majority of my knives are akin to a Yoshikane, within degrees, one way or another

I feel like the thickness matters more than the angle at the edge as it relates to strength of the edge.

So, in your experience, you're saying that (within reason, 10-15 deg) a more acute edge angle will have less of an impact on strength than the thickness BTE would. BTE thickness>semirational (10-15) sharpening angle, in terms of impact on edge strength?

 

[tostadas]

I dont fully understand your question. But what I can say is that I've used very nail flexing edges sharpened at conservative angles, and also robust edges sharpened at low angles. In this case of extremes, the more nail flexing one tends to be more fragile.

 

[Benuser]

All,

I hadn't given much thought to setting new angles on a primary bevels, most of mine are pretty thin BTE, but is 15 degrees where it should stop as a good angle without compromising too much? This would be on the paper steels and, say, 52100. Could lower angles like 10 degrees be ok, say on a protoypical Yoshikane 240 or an Eddworks? Without sacrificing edge retention too much?

I need to get better at sharpening overall, but I was curious where the limits were, and what the rule of thumb is, when it comes to primary bevel angles. I am not looking to get the sharpest angle ever but wanted some thoughts on how do discern which angle is right for a given blade where an ideal balance of retention and performance is achieved (theoretically).

There's some confusion. I guess it's the secondary bevel you mean, according to the terminology we use in this forum.
https://www.kitchenknifeforums.com/threads/primary-secondary-bevel-discrepancy.2231/
Anyway, it's the cutting edge you have in mind.
Much will depend on the steel you're dealing with. A hard steel with a very fine structure will take and hold much lower angled edges than a steel with large carbides. You may try to build a 12dps edge on, say, a soft stainless, but deburring it will become almost impossible. That's about taking an edge. Now the holding: if the steel lacks stability it won't hold it either.
You asked about paper steels. With e.g. Shirogami, you may well go lower than 10dps. Not so with Aogami Super which will benefit from a much more conservative edge, providing a spectacular edge retention.
In general, there is little interest in going too low as edge retention will suffer, while performance doesn't benefit much as long as the blade is thin enough BTE.
As for thinneth BTE, with a knife meant for general purposes with a lot of board contact, I'd aim for 0.2mm. More specialised knives may be much thinner. A thicker blade will require more force and result in a violent board contact.
I sharpen freehand. I want the right, convex bevel to flush with the face. So, I start at the lowest possible angle and will end at some 10-12°. The other side gets a narrow bevel at a much higher angle, 15-20°, depending on the steel. It works well for me, as a home cook. In a professional setting very different figures may be needed.

 

[pitted_soul]

I think I was meaning the talking about the primary bevels. I was referencing the 'thickness BTE' of my knives so give some context of what I am working with, but I am talking about the primary bevel on a double bevel knife. I was curious about the general thinking behind deciding on a primary bevel's total angle on a double beveled knife.

 

[pitted_soul]

Nope, I meant the 2ndary bevel ;-)

 

[Benuser]

Nope, I meant the 2ndary bevel ;-)

Do we agree you mean the cutting edge?

 

[pitted_soul]

Yes! Lol

 

[DoYoon Kim]

I fee like all my knives are just sharpened at whatever the height of my index finger is + masking tape.