Silly question about angles

[Alacrity]

Hey, so I have just a few questions that will probably seem silly to most of you knife aficionados on here but ones that I need to ask in order to clarify things in my head.

So lets say I am sharpening on a Lansky system at the 20 degree angle. Does that mean there is a 40 degree inclusive angle on my edge, or a 20 degree inclusive angle?

Another popular example would be a sharpmaker. Lets say I am using the 40 degree angle does this mean there are 20 degree angle edges comparable to lanskys or are the edges going to be 20 degrees more obtuse?

I'll think I have it straight...and then I read something and it gets all confused again.

Thanks for your patience and help,
Alacrity

 

[Omega Leather Works]

Hey, so I have just a few questions that will probably seem silly to most of you knife aficionados on here but ones that I need to ask in order to clarify things in my head.

So lets say I am sharpening on a Lansky system at the 20 degree angle. Does that mean there is a 40 degree inclusive angle on my edge, or a 20 degree inclusive angle?

Another popular example would be a sharpmaker. Lets say I am using the 40 degree angle does this mean there are 20 degree angle edges comparable to lanskys or are the edges going to be 20 degrees more obtuse?

I'll think I have it straight...and then I read something and it gets all confused again.

Thanks for your patience and help,
Alacrity

On the Lansky the indicated angle is per side. So if you sharpen both sides of your knife using the 17° slot you end up with a 34° inclusive bevel.

On the SM, the number is inclusive. So 40° nets 20° per side.

20° inclusive would be very acute. You'd be getting closer to razor angles than a typical knife and steel, heat treat and intended use would all be things to seriously consider. Most sharpeners are designed with far more obtuse angles in mind.

I think once you reprofile an edge to 20-25º inclusive it'll make more sense on just how acute that is. You won't logically confuse it with (most) factory bevels or pre-set sharpening system angles.

 

[Cypress]

Strigamort nailed it.

To give you an idea about angles, most of my Benchmades came from the factory with >50 degree inclusive bevels. I just reprofiled a new BM 810 today to 40 degrees inclusive with my Lansky system. It took FOREVER to apex the edge

 

[Obsessed with Edges]

Also keep in mind, the marked angles on the Lansky clamp are measured in reference to the immediate front edge of the clamp. Blade edges which extend beyond the front edge of the clamp (all will have to) will sharpen up at a somewhat lower angle than indicated. The further the blade edge is from the front of the clamp, the lower the angle will be. For example, a traditional folding pocketknife held in the milled notch at the end of the clamp's jaws, with a blade that's ~5/8" wide or so, will likely sharpen up at ~15°/side (30° inclusive), when using the hone in the '17' slot on the clamp. Wider blades extending further from the front edge will sharpen up at even lower angles.


David

 

[Alacrity]

Okay thanks so much, that helps a lot. It's all straight in my head now. I'm gona go with the sm so just wanted to make sure it was still giving the angles I wanted. Thanks again!