question about a sharp knife that cant cut tomatoes well

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When thinning, it seems to me we might need three descriptors; primary bevel, apex (or micro) bevel, and shoulder bevel.
 
So, I cut a half container up of grape tomatoes in quarters last night to add to the pesto we made. We pulled a couple of basil plants up and made lots of pesto. We invited neighbors over so we kind of had a wine party.

I used my Wusthof Classic 9-inch carving knife since I have not used it in a while. I was kind of checking it out for thanksgiving. It went right through those tomatoes without mashing any. I guess the knife is in good shape for Thanksgiving.

View attachment 147543
I've never tried a pesto with walnuts or pecans, I've always used pignoli nuts. How does it impact the flavor of the pesto?
 
I've never tried a pesto with walnuts or pecans, I've always used pignoli nuts. How does it impact the flavor of the pesto?

If you use fresh Texas pecans making pesto it takes a little more olive oil. I like the taste. I have never used walnuts. Not many walnuts around here. My pecans are free and fresh as I grow them.

Sometimes when we are making pesto, we add fresh hot peppers from the garden for a spicy flavor.
 
Rough steel rods certainly do create a burr, or even a wire edge exactly on top of the edge. Abrade it gently with a stone or a fine ceramic rod, don't push it back. It's weakened steel.
 
Rough steel rods certainly do create a burr, or even a wire edge exactly on top of the edge. Abrade it gently with a stone or a fine ceramic rod, don't push it back. It's weakened steel.
should i not use the honing rod ? because it does it everytime i use it
 
I would avoid any other steel rod than an extremely fine or a polished one.
even though the knife is something like 58 rockwell as one of the forum members stated ?
it gets dull preety fast
any alternatives to the rod ?
 
even though the knife is something like 58 rockwell as one of the forum members stated ?
it gets dull preety fast
any alternatives to the rod ?
A very smooth rod like a Dickoron Micro. A bit of overkill in a home setting. Or maintaining on a medium-fine stone, just as you deburr: a few very light edge leading strokes, ending with a few along the edge.
That’s all supposing a decent edge to start with, thin enough behind the edge, and not overly polished, as soft stainless won't hold.
I know three reasons for soft stainless not to hold: incomplete deburring; thickness behind the edge making you to use too much pressure, resulting in a hard board contact, especially on poly or bamboo boards; too high a finishing grit, making carbides breaking out of the already soft matrix who got further weakened by the polishing while the carbides remain intact.
 
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Has always confused the f out me too! I've considered asking about it a few times, but now mostly just use 'bevel' and 'edge', and hopefully it's clear from context what I'm talking about.

(Same as what @M1k3 said above.)
 
58rockwell I would say around 1k grit and stropping should give a good bite. Going much further will only loose the bite and beeing softer steel, it won't hold the edge very long so I wouldn't personally go much higher than 1k
that was the exact problems i finished at the 800gritstone deburred on it and stropped on leather for 3 times each side
and it cuts tomatoes brilliantly ...
the problem is that i was refining the edge too much
too much stropping on the leather
and going higher than 800 grit ruins the knife for cutting tomatoes like you said
 
any alternatives to the rod ?

A Concrete curb or cinder block and a raw piece of cardboard to strop on.

Edge trailing strokes only on both should make that steel-with-paper-clip-like-strength sharper than any rod.

And you won't have to worry about not raising a burr or knocking the burr off!

😅 😉 😁
 
A Concrete curb or cinder block and a raw piece of cardboard to strop on.

Edge trailing strokes only on both should make that steel-with-paper-clip-like-strength sharper than any rod.

And you won't have to worry about not raising a burr or knocking the burr off!

😅 😉 😁
hahahah so funny amazing
jk
 
A very smooth rod like a Dickoron Micro. A bit of overkill in a home setting. Or maintaining on a medium-fine stone, just as you deburr: a few very light edge leading strokes, ending with a few along the edge.
That’s all supposing a decent edge to start with, thin enough behind the edge, and not overly polished, as soft stainless won't hold.
I know three reasons for soft stainless not to hold: incomplete deburring; thickness behind the edge making you to use too much pressure, resulting in a hard board contact, especially on poly or bamboo boards; too high a finishing grit, making carbides breaking out of the already soft matrix who got further weakened by the polishing while the carbides remain intact.
ahhahah benuser how is it i asked about a knife at the same hardness as the cleaver and you said that touchup can be done using a stone
"Or maintaining on a medium-fine stone, just as you deburr:"
what do you consider a medium-fine stone ???
 
Around the 2000 gritt range. Some may say 1658 gritt, others will say 2769


And now, go to the stones and start sharpening.
I'm getting the feeling you want to theorize way too much, but you just need a lot more practise.

Use the tips that were given in some of your topics and start experiencing it.
You won't be able to use them all at once to full succes anyway, and you might even forget some since you asked and received a lot of tips.

Put on your Nike sweater and 'just do it'
 
Two things:
-There are multiple ways to rome, and you'll find different people have different habbits.
-HRC only tells part of the story... different knives being the same hardness but different steels can behave rather differently on the stones and/or have different edge longevity.
-Terms like 'soft steel' / 'hard steel' are all very relative...
 
Around the 2000 gritt range. Some may say 1658 gritt, others will say 2769


And now, go to the stones and start sharpening.
I'm getting the feeling you want to theorize way too much, but you just need a lot more practise.

Use the tips that were given in some of your topics and start experiencing it.
You won't be able to use them all at once to full succes anyway, and you might even forget some since you asked and received a lot of tips.

Put on your Nike sweater and 'just do it'
i dont have a 2k stone i used the 800 stone to do it and it worked fine
 
I did a couple of slightly exaggerated drawings to help anyone new understand this phenomenon...

If you cut down on a tomato at 90 degrees and perfectly straight; you will cut through it, no matter how overly refined your edge is. Like this:

View attachment 145710

But the majority of the time you're not neatly bisecting a tomato; you're cutting it at an angle, because a tomato is round. And to compound matters you might be using a push or pull cut, rather than chopping straight down. It looks more like this:

View attachment 145711

Where 'b' is the angle of your edge (sharpening angle). 'a' is 90 degrees minus 'b'. And 'c' is 90 degrees minus the angle you're cutting the tomato at. As soon as 'c' starts getting close to the same as 'a' - that's when you run into problems. And if 'c' is larger than 'a' - you’re really going to struggle if your edge is super slick.

Pretty much all cutting of stuff is the result of friction. If you don't have friction you can't cut anything. A tomato skin is fairly smooth, and if you combine that with a very refined edge you have quite a low coefficient of friction between the two. But that isn't the real kicker here... the really important thing is the 'normal force' exerted by the tomato upwards against your knife.

The normal force is obviously considerably reduced when you're cutting the curved surface of a tomato at an acute angle. And it's also reduced because the pulp is soft. The reason tomatoes are brought up again and again in this test isn't necessarily because the skin is unreasonably tough - the skin of a capsicum or bell pepper is probably tougher, and equally smooth. It's the combination of soft flesh, with skin that is both tough-ish, and smooth, that all together kill the friction generated when cutting it. Try cutting a wet tomato vs a dry one and you'll see the importance of friction.

But unfortunately, apart from making sure it's dry, you can't really change your tomato, so you have to change your knife. You could do this by lowering your sharpening angle, but that might make the edge less durable, and annoying to maintain. So you do it by finishing at a lower grit, with more teeth, and a higher coefficient of friction...

And now at last you can truly hope to achieve the bruschetta of your dreams, and know the panzanella in the mind of god!


[I think I've got most of that physics right anyway, and hopefully explained in a semi-understandable way.]
that was an amazing explanation IMHO
 
To feel a burr, you need to gently rub the side of the blade right over the edge with a down motion so that your finger crosses the apex, not going under it obviously. This is done perpendicularly, never rub along the edge.

Now if you had a metal ruler under hand, and would imagine it's your blade, and would reproduce that motion, you wouldn't feel a thing as your finger rubs at the very edge: it would be smooth. A knife without a burr feels just like that.

A burr feels like not so freshly shaven beard. We all have different strength of beard, but let's suppose in my case a burr out of a 5K would feel like almost nothing: really freshly shaven, but detectable depending on finger sensitivity. From a coarse stone, it would feel like a two days shave with the same amount of strokes, and from mid stone, like a one day shave.

Hence why people when sharpening soft dull SS will take a coarse stone and say they sharpen until getting a real "hairy" burr. Perhaps a three days shave to me.
interesting so basically you describe it as more of a rough where the burr is vs smooth on the side you were grinding and not like most folks say you feel a "catch"
 
Dear mr r0bz,

Have you allready sharpenend a knive at the angle of 50 degrees or so, like suggested a while ago? There will be a huuuuuuuuuuuuuge burr, not possible to miss.

Searching for a nuance on how people describe or name the feeling of a burr, will not make you feel a burr any better.

I admire your questioning and thoroughness, but beware you don't make quantum mechanics out of peanuts.

Go sharpen at 50 degrees angle! Now! and celebreate the feeling of a burr with us!
 
Dear mr r0bz,

Have you allready sharpenend a knive at the angle of 50 degrees or so, like suggested a while ago? There will be a huuuuuuuuuuuuuge burr, not possible to miss.

Searching for a nuance on how people describe or name the feeling of a burr, will not make you feel a burr any better.

I admire your questioning and thoroughness, but beware you don't make quantum mechanics out of peanuts.

Go sharpen at 50 degrees angle! Now! and celebreate the feeling of a burr with us!
i do know how a burr feels like i raised many and felt many by now
 
interesting so basically you describe it as more of a rough where the burr is vs smooth on the side you were grinding and not like most folks say you feel a "catch"
I wasn’t aware so much of talking about a catch although I do understand. I’m aware of a lot of talking about a burr as « hairy ». Of course up to the finest grit if you reduced and deburred, more like catch perhaps. That would be someplace along the edge improperly deburred in my book, not the « burr » as a result of primary sharpening. Cutting paper a small section improperly deburred does « catch » against an otherwise smooth experience.
 
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