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Redheads, nice knife collection!

re: “What did you think about my dumb idea of twisting the knife clamp around the z-axis. (major mod)”

I’m not sure I understand what that twisting of the clamp would do. It seems like you’d want to maintain the plane that bisects the centerline of the knife blade and just vary the x-y position (either of the…[Read more]

I’ll try one more idea. See if you buy this:

In dark orange, I drew a funky hypothetical blade shape on the back 70% of the chef’s knife edge, in hopes of making my point clearer. It curves down off the ideal circle and then has a break point and then a perfectly straight portion labeled as X (green text), out to the heel. I don’t know what you’d…[Read more]

I kinda feel like the Spyderco LionSpy reinforces my point. Here’s a zoomed view, and note the scale is much coarser than the chef’s knife. On the straight part of the blade (and keep in mind this is a small knife) the angle deviation gets progressively greater than zero (relative to 15* target) as you get father away from the circle centerpoint…[Read more]

That’s a good idea to combine the AG and the curves (but maybe just the vertical lines if the curves are in there too?), and I’d agree that a bigger alignment guide might make sense. But you’d have to be sure the reference point for the curves lines up right.

Personally, the way I use the AG is I put the inside corner on the upper right corner of…[Read more]

What if we inserted a 12″ long straight segment into that chef’s knife beginning at x= -4 (so the heel would now be at x= -16.5). Per the “law of straight blades sharpened on a spherical ball joint” the simulation result should show zero angle deviation (even if we tilted this straight segment at an angle). But if I’m understanding the way he set…[Read more]

But the blade is straight from at least -2 to the heel, and only a small deviation from straight beginning somewhere between 0 and -1. You’re drawing the green line to match the simulation output, not the knife. If you didn’t have that simulation output, knowing what you know about sharpening straight blades regardless of the tilt, where would you…[Read more]

Justin and all, there’s a contradiction in the results in Anthony Yan’s paper between section 5 and section 6, and you have to read between the lines and try to understand what the limitations on his circular blade simulations are, in order to resolve the contradiction.

In section 5 (in particular section 5.3, pg 53) he concludes that for a s…[Read more]

Are you guys talking about the screw into the divots of the angle bar, or the nut on the fine-adjust screw?

On my angle bar screw, I’m not sure how you’d get the mechanism to slide to a different angle if you inserted a BB or wire insulation between the tip of the screw and the divot in the bar. And my fine-adjust screw seems like it is one…[Read more]

Justin, that sounds like the video that revived this discussion in the first place.

There are certainly limits on what a spherical ball joint sharpener can be expected to do at a single clamp point (and Anthony Yan’s paper covers those limits), but there must also be a pretty high percentage of knives where the user can get satisfactory to…[Read more]

How to draw a semi-circle template for a GEN3-2017 vise, to overlay onto a circle contour jig:

Of course, nobody should actually sharpen a knife based on this until someone with some WE experience and credibility has given their OK. I’m just describing the process for creating the circle template based on the latest info on where the…[Read more]

Marc, was I able to address your question re: the angle bar setting not being a factor for the circle contours, or if not, please make any additional points you don’t feel are addressed.

Maybe another way to look at it is that the blade profile (outline) is matched to the circles on the jig, not the bevel. The sharpening angle can be anything…[Read more]

tcmeyer, re: “I extended the adjustment screw and added a knob.  I then added a 0-9 scale to the knob’s hub.  For angles in the 20-dps range, each 1/10th of a turn is about 0.03 degrees.”

I like it! Nice work. I’ve been using a “caveman” version of that, where I take the height(depth) gauge that is in the end of most calipers and just log the hei…[Read more]

BTW, how come posts are appearing out of order? They used to be chronological, and now new posts sometimes get inserted in different places, earlier in time. Chronological is easier to follow and not miss new posts. Is there a setting I control that with?

Marc, on your 1st point, I don’t know enough about the past WE models to comment on whether a universal jig is possible (and all bets are off with past models that did not have a spherical joint).

But I’d offer this thought to ponder: even assuming a model with a spherical joint, and even if the distance from the pivot point to our reference…[Read more]

I noticed the round knurled nut on the fine-adjust screw coming loose (I assume that’s what you mean by outer screw?). I was thinking maybe a star washer under the nut might do the trick but haven’t tried it yet. Or maybe a couple wraps of teflon tape on the threads.

Dwight, what do you mean by “nylon BB?”

I read the relevant parts of Anthony Yan’s paper that Redheads referenced above in post #44099 (the first link). It’s quite an impressive body of work, and it’s too bad that Anthony is no longer posting.

In Anthony’s paper on pg 53 he summarizes the straight blade case (using a tanto blade with a straight main blade and a straight but angled…[Read more]

It would be fine with me if moderators want to move this thread into “Techniques and Sharpening Strategies” >> “Advanced Techniques and Sharpening Strategies” sub-forum. Maybe that would eliminate the angst some of you guys feel about it.

I just put it in the “Basic Techniques” sub-forum because I’m still a novice with the WE, and because the…[Read more]

Keep in mind that the original objective was/is to see if it’s possible to develop a knife alignment jig FOR THE VERY REASON of simplifying the knife positioning down to an easy-to-follow and repeatable process (for beginners and experienced users alike). It’s to eliminate the guesswork and trial-and-error.

It’s looking like there is some family…[Read more]

Yes, the pins are a very tight fit, but they will fit. They will loosen up a bit after a few insertions/extractions, but they need to be a tight fit so that the guide doesn’t have slop it it. Maybe add some dish soap to the pins for the first few insertions/extractions?

I would not advise drilling it to slightly increase the diameter (more likely…[Read more]