View Full Version : Fundamentals of angles and sharpening questions.

07-08-2013, 11:38 PM
Is there a easy method that I can use at home to measure the angle of a bevel on my knives? I'm starting to understand asymmetry and the importance of angles in general, but I'm still struggling with knowing what type of angle I'm producing after sharpening. If I wanted to take a knife from 50/50 degree biased to a 90/10 or so, is it possible? I've been playing with some old double bevel Shuns and it seems no matter how hard I try they end up close to equal angles on both sides. Does the initial 'OOB' angle set me up for lifetime of something similar? Thanks again for all the awesome advice.

NO ChoP!
07-08-2013, 11:54 PM
When setting bevels, you should start with a low grit stone. What grit are you using?

07-08-2013, 11:57 PM
Right now I only have 1k and 5k Gesshin stones. I tried to find courser ones in Japan a month or so back, but it seemed the shop keep was hesitant to sell me something so course in fear I'd mess up my knives.

NO ChoP!
07-08-2013, 11:59 PM
I should add, when I say low, I go down to 140, 220, 320 and 500 dependent on how aggressive I want to get.

NO ChoP!
07-09-2013, 12:01 AM
Valid concern for sure, but for changing bevels, I'd at the very least check out the Beston 500

07-09-2013, 12:15 AM
I can't recommend some kind of tool for magnifying enough. This will help you to clearly see whether you are hitting the blade face, edge shoulder, edge bevel, or edge very clearly....the sharpie trick makes this easier too.

Getting this right will be the key to setting new bevels the way you want....whether you will be happy with those bevels is a totally different question ;)

sachem allison
07-09-2013, 01:54 AM
changing a 50/50 to a 90/10 you are going to lose a hell of a lot of metal I imagine. That's a hell of a change.

Brad Gibson
07-09-2013, 02:12 AM
i moved my first knife from 50/50 to about 80/20 over around 20 sharpenings. it took quite a while to achieve the edge and each time it gained a higher grade of sharpness but lost edge retention. I'd recommend keeping the origional profile on your knives

07-09-2013, 09:25 AM
...I always fall back to "Why?" and "If you have to ask, you probably shouldn't...?, and with that out of the way...I guess the easy method would be keeping track of your sharpening angle. Changing from 12.5* per side to 22.5* and 2.5* (almost flat to the stone) will get you there.

I'm pretty sure in the past Dave has advised not doing this to most knives. If the knife is significantly asymmetrical in grind (spine to edge, not just edge bevel) you could be really swimming upstream, and with thinner blades ( Tadatsuna?) do you really accomplish anything important?

07-09-2013, 10:20 AM
If you really want to do this, you do not necessarily need to change the angle at which the bevel is set, but simply sharpen on one side only, and just deburr on the other.

Don't do this all at once, over a course of many sharpenings is much wiser, because you have the opportunity to slowly gauge how your progress is affecting the cutting performance.

The ratio of 50:50, 60:40 or 90:10, has nothing to do with the angle per se, but the size of the bevel. For example, my Tojiro honesuki is sharpened at about 95:5, but is sharpened at about 14-15 degrees on both sides, the front is where all of the sharpening is done, on the back i just deburr on each stone.

Read this excellent thread for a good discussion of this:


07-09-2013, 12:02 PM
I suggest doing what Brad did. Enjoy your knife. Get to know it. :) As for angles, thinner is better. Don't worry about the angles. If you want to play with them, use magic marker and start thinning incrementally from the shoulder on your bevel and work down to the edge. When your edge starts failing too soon, put a microbevel on it and you've found your preferred angles, whatever they may be.