Thumbnail test after stropping

[naptight]

Hello.

Wondering what method people use to test their knife sharpness? And if the thumbnail test is the best way, besides actually cutting food, to do so?

Im new to sharpening kitchen knives. I've had mixed results. Ultimately, I think everything I've attempted to sharpen has gotten sharper than when I started. But, a couple of my attempts haven't resulted in enough performance for me to be happy. But, a few have resulted in incredible performance for my standards. Anyways, one thing I noticed is If I do the thumbnail test immediately after I deburr coming off the SG500 or SG2000 the edge feels sticky and really wants to bite into my nail. But, if I strop, even just a few light passes on my roo leather and with one micron diamond spray, the edge won't bite on my nail anymore. It basically feels just as slick on my nail as it did from the factory. Do you think I'm stropping incorrectly? Or I'm just getting all the bite out of the blade?

 

[HumbleHomeCook]

Hello.

Wondering what method people use to test their knife sharpness? And if the thumbnail test is the best way, besides actually cutting food, to do so?

Im new to sharpening kitchen knives. I've had mixed results. Ultimately, I think everything I've attempted to sharpen has gotten sharper than when I started. But, a couple of my attempts haven't resulted in enough performance for me to be happy. But, a few have resulted in incredible performance for my standards. Anyways, one thing I noticed is If I do the thumbnail test immediately after I deburr coming off the SG500 or SG2000 the edge feels sticky and really wants to bite into my nail. But, if I strop, even just a few light passes on my roo leather and with one micron diamond spray, the edge won't bite on my nail anymore. It basically feels just as slick on my nail as it did from the factory. Do you think I'm stropping incorrectly? Or I'm just getting all the bite out of the blade?

I suspect you're rounding your apex during stropping.

 

[naptight]

I suspect you're rounding your apex during stropping.

Sheeeeeeeeeeeeeeeet

 

[Pie]

I suspect this happens to me. The solution was to stop stropping entirely.

 

[Genghis_F]

My test is paper towel held by one corner
The knife should glide thru without tearing and with minimal sound
I find stropping definitely improves performance here
Sometimes you don’t even need the stones, just touch up in strop

 

[Mr Kooby Shemayrew]

My test is paper towel held by one corner
The knife should glide thru without tearing and with minimal sound
I find stropping definitely improves performance here
Sometimes you don’t even need the stones, just touch up in strop

This is a good method to determine 1) the quality of your edges straight off the stones, and 2) if your stropping technique is improving or worsening your edges.

I took some kitchen knives to a Norton India combo stone a few days ago. The India fine is listed as 400 grit but it finishes effectively about 800. Sharp with very good bite. It feels sharp.

Next, I took it to an Oozuku Mizu Asagi razor hone. It felt duller coming off this stone and duller still after stropping. The paper towel test said otherwise as it glided through. The stone and strop had removed the bite but increased sharpness. Feel is a good indicator but sometimes it can be wrong. The paper towel helps confirm when there is a question.

 

[mengwong]

one thing I noticed is If I do the thumbnail test immediately after I deburr

Quick sanity check – are you testing both sides of the edge? Like, when I do the thumbnail test, first the tip faces away from me. Then I switch so it faces toward me. Should catch both ways. Or, more practically, you can slant the knife so it cuts toward your knuckle vs toward the nail.