Can't hit the last top inch on the Left side?

[Expidia]

Oneida old beater chefs knife that I used to use to chop frozen food.  Figured I’d try to see how good an edge I could put on it.

Factory bevel after using marker and a stone looks to be 15 degees which I set with an angle cube.

The right side after the 100 & 200 grit stones is coming along good.  But this has happened to me before where I can’t hit the marker on the last inch towards the tip along the top edge. Happened to me on another knife, but the right side top tip area.  The rest of the bevel to the back is coming along fine on this one.  Its like a secondary bevel is near the tip that I cant reach with the stone.

Do I keep going until even more metal is taken off to finally hit that top edge area?

2017 Gen III vice which is holding the knife in place fine.

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[Organic]

I would drop back to the 100 stones and re-mark the bevel with sharpie then keep going until all of the sharpie is removed from the entire bevel. It also looks like you didn’t apex the very tip of the blade, so I would spend some extra time working just the tip area. It is often the heel and the tip that are the hardest areas to get.

It will be interesting to see how that 15 degree per side bevel holds up after hacking away at frozen food. I suspect it won’t last long.

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sksharp, Expidia

[Expidia]

Yeah, I’m noticing my Wusthof knives that I already did at 14 degrees are starting to show slight micro chipping.  Even though Ima

somput on a micro bevel on them.  I don’t care because if I do them all over at say 17 this puts me over 30 knives for breaking in the stones.

So do you think I should jump to 17 on this one which would widen the entire bevel and a better chance of hitting the point of the apex without taking off too much more metal ?

[Organic]

That’s a call only you can make. Its just a matter of personal preference. If the knife is primarily used for chopping through frozen foods I would probably go to 20 per side, but its a cheap knife so there’s no sense in worrying too much about it. Cheap knives can be great because you can try lots of things and you don’t have to worry about the wear and tear.

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Expidia

[Expidia]

Thx organic.  That was it.  I dropped down to 17 degrees and re-profiled the bevel and at that wider angle I was finally able to hit the front extra bevel with some extra work.  This knife never had much of an edge so I used it as a chopper.  But its probably 30 years old and might have been of quality steel because its been work with the 100’s to cut that initial 17 degree bevel.

If it holds an edge well then I’ll graduate it to my chef knife rack.

[tcmeyer]

Expidia wrote:

Do I keep going until even more metal is taken off to finally hit that top edge area?

I think this is a case for “finding the sweet spot.”  I would move the knife back toward you, so that the last forward sweep of the edge seems to have a focal point very near to alignment with the pivot joints.  Keep moving it in increments until your stone removed all or nearly all of the marker at the tip.

I sharpen all of my knives to 20 dps +/- 3dps.  Exceptions are high-end knives, where the steel can stand up to the abuse of general kitchen knife work, or where the original factory edge calls for something different.  Some examples:  Martinii filet knives are sharpened to 22 dps, according to their general manager during a TV tour of their factory.  My Aritsugu santoku came with a 6 dps symmetrical factory edge, which I found was too fragile for my (ab)use, so I’ve sharpened it to 10 dps.  I’ve been told that skinners should have  more obtuse edge – maybe in the range of 24-30 dps.

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sksharp, Marc H, Expidia

[Expidia]

Thanks TC for those placement tips and various edge angles.  I’ll re-read that 4 part finding the sweet spot sticky too.  It seems to happen more when I do long knives which the tip flexes easily and I have to hold the opposite side of the stone Im working on.  Its not the motion of the arms to the curve of the knife because Im just scrubbing up and down having to work those tips more.  I use a small piece of scrap wood in my hand to support the tip from pulling to either side even with light stone pressure.  The wood works nice for me as it keeps my fingers cleaner.  Touching the opposite side while profiling leaves a lot of grey residual on my fingers so I have to keep washing them.  I have not started using the wet the stone on a sponge tip or spraying water on the stones as Im sure that can be messy too, metal sludge wise.

I guess I could do a long knife in two parts too.  Pulling the tip closer to the pivot points was something I was thinking of trying, but I wanted re-read the sweet spot posting anyway before I tried that.

Also, with re-profiling an initial knife earlier I started with the 50/80 grit which tore through any knife’s initial stage quickly, but then it added a lot more time for me getting those deep scratches out with the 100/200.  I start with those now but it definitely adds time to the process as the 50/80 are new like the rest of my stones.  The 50/80 are used less by me now and they are still very scratchy.

I had to do a lot of scrubbing near the tip to finally get at that marker on the apex. Then the same for the other side to keep the bevels even. But I think the chefs choice electric sharpener that I was using for years which gives you a sharp edge, but a rounded bevel. Those rotating stones might have also concaved that tip a little which collected more marker as when pulling the longer knives out of the grinding wheels I could feel the tip slightly drop onto the wheel.  And it also takes time for the WE to get rid of that rounded bevel with the 100 stone.

[sksharp]

I put a stone on the rod with a stop to hold the stone in place.  Mark or note the stone where it contacts the blade directly over the clamp. Then move the stone toward the tip without moving the stone off the stop. You want the stone to stay in the same position all the way to the tip of the knife, not falling below or rising above the contact point you established over the clamp. As long as the curve of the knife matches the arc of the arm and stone the angle will not change. Thus the sweet spot!

The way the knife is clamped in the above photo, I would expect that the angle is as much as 2 degrees more acute than the heel of the blade. I would move the knife probably 2 or 3 inches more toward the tip to even out the angle along the edge.

When the point on the stone(see above explanation)falls below the edge the angle is more acute, if it rises above the edge the angle more obtuse.  This arc has the exact same effect on the angle as lowering or raising the knife in the clamp. As long as your edge is on the same plain as the arc of the arms the angle will not change.

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Expidia, Marc H

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