Laser guided edge angle

[Crox]

I picked up this toy goniometer for fun. Here is Spyderco factory edge:

And mine from freehand bench stones. I am satisfied with the sharpness I get. And I know / expect some edge convex. I wonder what’s reasonable/possible freehand? I feel like BBB has posted some that are near perfect like factory, but can’t remember. Aspirations…..

[Scandi Grind]

I like freehanding, but because I don't have one of these laser thingies I don't technically know how much convex I am introducing to the edge. However, I don't think convexity is all too bad a thing as long as you can apex and deburr the edge consistently. If your freehanded convex edges don't slice as well as you like, you just go steeper sharpening angle and the convex shape will probably hold the steeper edge without an issue. It's always easy to go steeper when you are freehanding.

[Crox]

I like freehanding, but because I don't have one of these laser thingies I don't technically know how much convex I am introducing to the edge. However, I don't think convexity is all too bad a thing as long as you can apex and deburr the edge consistently. If your freehanded convex edges don't slice as well as you like, you just go steeper sharpening angle and the convex shape will probably hold the steeper edge without an issue. It's always easy to go steeper when you are freehanding.

Yeah I want to go steeper and that was the origin of trying this out to see about where I was.

If I’m thinking about it correctly, it must be the larger part of the blob at the apex. So I am at a stubby 22 or so degrees per side.

This is kind of my natural angle so I’ll need to train for a more shallow angle.

[Jeb]

Have not seen one of those, pretty neat if you ask me, just have to wonder how accurate that sucker is?
If you can, which I am not sure, not seeing the whole thing.
Measure your knife edge with it one way laid out across it, then flip your knife over a 180 degrees with the handle on the other side, that is if you can. You would know then just how close to square on your Lazer is.

Just a thought, and something else cool to mess with. It's like all my levels, not a single one perfect if you check them by flipping them. So I mark each end of all my levels and I use them with the mark running the same way no matter what, this way it stays consistent.

[Crox]

Have not seen one of those, pretty neat if you ask me, just have to wonder how accurate that sucker is?
If you can, which I am not sure, not seeing the whole thing.
Measure your knife edge with it one way laid out across it, then flip your knife over a 180 degrees with the handle on the other side, that is if you can. You would know then just how close to square on your Lazer is.

Just a thought, and something else cool to mess with. It's like all my levels, not a single one perfect if you check them by flipping them. So I mark each end of all my levels and I use them with the mark running the same way no matter what, this way it stays consistent.

Yeah it’s cheap so I don’t have high expectations for accuracy. However, I think 17 degrees per side is the quoted factory angle. That would match what I see here. Also it came with a “calibration” blade at 10 degrees with 14 degrees micro bevel and that matched. Should give me an idea while I play with freehand angle anyway.

[Scandi Grind]

Yeah I want to go steeper and that was the origin of trying this out to see about where I was.

If I’m thinking about it correctly, it must be the larger part of the blob at the apex. So I am at a stubby 22 or so degrees per side.

This is kind of my natural angle so I’ll need to train for a more shallow angle.

You can get cheap plastic angle wedges that give you a referrence point for your angle. I have some and use them all the time to imprint what angle I'm trying to hold for a particular knife.

[Crox]

Yeah I want to go steeper and that was the origin of trying this out to see about where I was.

If I’m thinking about it correctly, it must be the larger part of the blob at the apex. So I am at a stubby 22 or so degrees per side.

This is kind of my natural angle so I’ll need to train for a more shallow angle.

You can get cheap plastic angle wedges that give you a referrence point for your angle. I have some and use them all the time to imprint what angle I'm trying to hold for a particular knife.

Yes, but do they have frickin’ lasers beams??

[Mage7]

I like freehanding, but because I don't have one of these laser thingies I don't technically know how much convex I am introducing to the edge. However, I don't think convexity is all too bad a thing as long as you can apex and deburr the edge consistently. If your freehanded convex edges don't slice as well as you like, you just go steeper sharpening angle and the convex shape will probably hold the steeper edge without an issue. It's always easy to go steeper when you are freehanding.

Yeah I want to go steeper and that was the origin of trying this out to see about where I was.

If I’m thinking about it correctly, it must be the larger part of the blob at the apex. So I am at a stubby 22 or so degrees per side.

This is kind of my natural angle so I’ll need to train for a more shallow angle.

Yup, you wanna count at the very edge of where the reflected light stops.

I posted a little bit about mine here: viewtopic.php?t=96867&start=180#p1820451

That one is supposedly a little better made and is only quoted for +/- 2 degrees. I think the CATRA one had a similar tolerance for the "hobby" version but not sure about the more expensive model. I wouldn't recommend the Grit-O-Matic until they work out some of the kinks.

The primary downside of yours is simply that the laser beam may not be perfectly centered at 0, but as I am sure you've noticed by now, that doesn't really matter too much and you can just adjust the scale/laser orientation until the reflections off the primary grind are equidistant. I mean, as long as you know you've got a quality ground blade you can count on the primary blade grind being equal enough--closer than the tolerances of the tool anyway.