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Phil,

I'm not sure I understood properly, but I think what you're measuring with your AngleCube or such is the angle between the horizontal plane and the side of the blade.

The main part of the difference here is that the knife does not contact the wheel exactly at the top of the wheel. So to find the correct angle, you'd have to mark the radius of the wheel at which the apex of the knife makes contact, then measure the angle between this radius and the vertical, and subtract this angle from what you found previously (if the contact happens further away than the top of the wheel, which is usually the case).

You are also dealing with a lesser error : the blade is usually tapered, so the side of the blade is usually at an angle with the plane of symmetry of the blade. So you'd have to measure the taper angle : you can clamp the blade in a vise and take one measurement on each side, then divide the difference by two. Once you have this difference, you have to subtract it to the angle you read on the angle cube resting on the side of the blade.

For more on this, here is a link to a geogebra page I designed where you can easily play with this subject, no advanced mathematics involved. The first error is the angle between the dashed line (from the center of the wheel to the point of contact) and the vertical axis. Or the other dashed line (tangent to the wheel at the point of contact) and the horizontal axis.

Hope this helps !

Hello !

Have you tried Rich's website ?

A bit more food for thought on this ultrasonic deburring thing :

https://www.blackstone-ney.com/blog/ultrasonics-deburring-fact-or-fantasy/

This report was shared by the author and discussed in this thread on the forum

I was lucky to find this, it's classified as a reading light but it's led with three colors and flexible.  It's perfect for sharpening.

Wow, it looks very nice, not only for sharpening but also for having around the workshop. Care to share a link ?

I have found that it is much easier to get low BESS scores when I sharpen at low angles (sub-15 dps). In my experience diamond stones tend to produce lower scores than the SG-250, and higher grit finishes (1000+) produce lower scores than lower grit finishes.

Just to make sure : when you talk about lower scores, do you mean lower BESS number or lower sharpness ?

I used to chase BESS scores initially. It is a good tool to measure progress while you develop a technique. After a while I got too lazy to fire up the BESS tester, but I still do occasionally. In my experience you quickly get a feel for a sharp burr-free edge by how effortlessly it glides through phone book or cigarette paper, you don't even need to test.

I wholeheartedly agree, once you get comfortable with the process, there is little need for systematic BESS testing. When I get a new, exotic steel I usually test it before/After.  Plus high BESS does not necessarily translate to higher edge retention, so I use it only as a reference to see if a given sharpening is consistent with the lot, if I have a doubt.

Although this may be the case in some instances, but for me, there have been times that I'm finishing off with the above numbers, but still running the knife through my microscope and it clearly shows no burr is present.

In my experience some steels never get under 130 BESS. I have a few french Sabatier knives that won't get under 150, 130 at the very best, no matter what. And they get back to a lofty 250 after a few uses in the kitchen. Those I don't trust to care for knives get to use them, but my 8 y.o. son uses my japanese knives.

Also, I've experienced some situations (edge leading with SJ-250, on soft steels) where there is still a layer of very soft steel at the apex of the edge. It is however invisible under a typical optical microscope.

In my experience, the composite wheel has less feedback than the leather wheel with the compound. Still, John's advice is excellent advice.

When honing with the composite wheel, I prefer to add a few drops of water or the friction feels too high. Also, to be honest I don't think your edge will roll over due to the angle being (reasonably) too high, or the pressure being a (reasonable) bit too high. What I found is I tended to be apply a more constant pressure and moving more slowly when using a jig, therefore being much more efficient.

You may learn a lot by conducting a few experiments :
- If you hone a knife freehand, test it, then hone it righ afterwards at a controlled angle, then retest it : does sharpness increase ? If yes, you are not dulling the edge freehand, you are not honing efficiently.
- If you do it the other way around, does sharpness decrease ? If yes, you may be misjudging your honing angle *a lot* when freehanding. Using a sharpie might help.

You could also confirm your findings by looking at your edge under a microscope after freehanding : do you see a burr ? Does cutting a taunt nylon wire (BESS or DIY) leave a dent in the edge ? Those would confirm that freehand honing is not efficient, or not enough.


Also, honing with a jig but not honing enough might be just what it takes for the knife to feel sharp when testing it on a sheet of paper. But there will still be a burr. If you don't hone enough freehand, the burr will be there but will not have such a consistent angle, so it will not feel as sharp. I feel that I have to hone for a longer time when using the composite wheel compared to the leather wheel.

Very nice job !

The thing is, the tip has been rounded out by removing metal, so there is no real way to bring everything back to how it should be. If you want to restore the angle of the tip as it was initially, the best option would probably be to sand one or two millimeters out of the entire height of the blade end, at the original angle.

As it is heavy work, and probably not that important, I would go the belt sander or wheel side way for just a tiny bit to reduce the bevel at the tip and bring it closer to a point.

Then sharpen it as required. You may have to lift the tip a tiny bit, and/or pivot slightly, depending on how the bevel goes at the tip.

Lifting does not round out the tip if done properly, keeping the tip clear from the stone's shoulders until the end. But it should barely be required here, as the edge does not curve upward too much.  If anything, lifting increases the angle, so it reduces bevel height, which is exactly what you want in this case at the tip. Don't pivot away from you too much.

I think knife restoration experts such as @Kwakster will have dealt with much worse and could provide useful insight...

And cleverly enough, if you don't enter anything in the input box next to the search button at the top, it will graciously redirect you to the same options window.

So when I search for words only, I use it, and also if I need to add a few options.

Also, when you're in a given topic/board, the dropdown next to the top search button will default to "this topic"/"this board" so you will only get hits inside the current context. But you can still revert it to "Entire forum".

I have no experience with these, and my go-to website (Rich's Sharpening Handbook) doesn't either.

No Tormek jig will help you in this case. If I *really* wanted to sharpen these on a Tormek, I'd use a MB-100/MB-102 and a drill collar  to sharpen the rounded sides of the point on the side of a diamond wheel. Or you could do it freehand. Then sharpen the flat faces of the point on the sides/shoulders of the diamond wheel.

But a belt sander or a simple diamond plate will be much better suited. One word of caution : you should try to limit sharpening the sides to the bare minimum (ie stay close to the point) to avoid changing the diameter of the bit.

Welcome to the forum.

It is in the upper right corner as seen in the attached picture.

I think this new kit is a good idea in principle.

Where I live, the kit is roughly equivalent to a free KJ-145 + free storage box + free magnifier. For those who have use of these, it could be worth buying with their initial Tormek purchase.

I fully agree : I have set up an Ikea ceiling light with multiple spotlights so the Tormek is lit from different angles.

I believe that whatever burr is still here after sharpening will be taken care of by the grass itself, and a thick branch or loose stone will nick the blade no matter what.

The wear on the SG stone and the hassle of setting up the Tormek for lawnmower blades make it ill suited to the task, especially when one includes the time required to true the SG afterwards.

The system mentioned by GeoBoy makes much sense for people who do that on a regular basis and for people who do that only occasionally, a belt sander,  bench grinder or angle grinder will work better and faster.