Spyderco Forums

It would appear be a waste to leave this at the standard 30 degree with 40 degree microbevel.

How low can we go?

How low an angle you can sharpen to, and how thin behind the edge you can go, will somewhat be dictated by your own unique usage and cutting style, rather than a set number.

Obviously materials properties play a part too, but in high edge stability steels, I generally go as thin as I can until the edge starts to fail in normal use (by chipping out or rolling). Then I either sharpen to a slightly more obtuse angle until the edge is satisfactorily stable, or apply a light microbevel, and there you have your optimum high performance edge angle.

People's different cutting styles and common tasks introduce a lot of variables. There was an interesting post on here or another forum recently, which mentioned how long the finely sharpened, acute edge of a kitchen knife lasted. For the poster it was a matter of weeks or months (presumably with stropping and/or steeling from time to time). When his wife used the knife, the same freshly sharpened edge was trashed in a week or less, due to her different techniques and level of care, despite both of them basically cutting the same materials.

I think the grind on the blade flats would be around 7 degrees, so I'm going to try around 12 degrees per side to start with.

For comparison, the factory grind on most (non Robust) Moras is 23 inclusive.

Some of my VG10 Japanese chef knives run around 0.006"-0.007" thick behind the edge, so AEB-L should have no problem going quite thin and acutely ground.

Does anyone know what hardness range these ended up coming in at?

My understanding (which could be totally wrong) is that AEB-L is a bit tough, so perhaps it could withstand the low angles you're looking for. I love those kinds of steels

I run K390 on my Urban at 30 no issues, been using the same edge since November with only stropping

You're going to have to experiment. If it were me I'd try thin first. Maybe 10-12dps. But keep the concept of fatigued steel in mind, which may take 2-4 sharpenings to remove (or, it could be fine from the get-go, you never know). If 10-12dps yielded edge damage that I deemed premature or unacceptable, I'll microbevel it and continue experimenting, taking mental notes of performance along the way. By the time it needs a reprofile, I'll have a better idea as to what it can handle for my uses.

You can probably get away with 10dps with a micro bevel just fine for most tasks so long as you aren't batonning hard wood knots.

If AEB-L is sort of a stain-resistant 52100, as I understand it to be (correct me if I’m wrong), it has a lowish carbide volume of smallish carbides and can thus be taken to lowish angles IF the carbide-holding matrix is hard(ish enough).

As we don’t know this Urban’s HRC range, experimentation is the order of the day.

I'm debating on taking it to the CBN rods on the Sharpmaker at the 30 degree setting and see how it does.

Just reprofiled to 15dps (30 inclusive) with sharpmaker. Not as fast as H-1 to reprofile not as slow as K390. Reminds me a bit of H1 in the polish that it takes though. Seemed to respond well to the fine and ultrafine stones. Takes a keen edge using the sharpmaker and a strop.

The edge was not the greatest out of the box, but I'm really liking it now. Took a while to reprofile to 15dps, so I'll probably leave it there for a while. Might go more acute in the future. Want to see how it wears at this geometry first.

Beard Hair Test :D

Nicely done Matt! Funny last night I was looking at that Para 3 I was talking about in the other thread, then at this knife and thought...Maybe I'll attack that Urban first because of the easier to sharpen steel. That whittled hair has me leaning towards this knife first now!

Very sharp looking, never met a 15 dps angle I didn't like :)

Less is more. Well, until less is too much. :)

It all really depends on your uses as well as how you use your knife. Just because one person can get away with 20 inclusive doesn’t mean that the next guy isn’t better off at 30.

Be a man: 10 dps FTW!

I'm trying out this angle for now.

ChrisinHove wrote: ↑

Wed Jun 19, 2019 1:10 am

It would appear be a waste to leave this at the standard 30 degree with 40 degree microbevel.

I'd say that about every steel Spyderco uses to be honest. I can't remember the last time I kept a knife ground that thick rather than taking it down to about 10dps with a 15dps microbevel.

jpm2 wrote: ↑

Fri Jun 28, 2019 3:01 pm

I'm trying out this angle for now.

Alright!

jpm2 wrote: ↑

Fri Jun 28, 2019 3:01 pm

I'm trying out this angle for now.

Have you thought about thinning the blade itself? I got one of those as well, and I will be thinning out the blade over time. I do a little here and there.

p_atrick wrote: ↑

Fri Jun 28, 2019 4:23 pm

jpm2 wrote: ↑

Fri Jun 28, 2019 3:01 pm

I'm trying out this angle for now.

Have you thought about thinning the blade itself? I got one of those as well, and I will be thinning out the blade over time. I do a little here and there.

I do it like you, a little at a time. First working my way up from the edge, then back down.