Daily microscope pics

[mengwong]

A thread to geek out and zoom in. Blow up those bevels, expand your edges, eyeball that apex…

Suggestions: If it’s your first time posting with a particular setup, include

• a photo of a ruler showing millimeter markings for scale
• make and model

Loupes and SEMs equally welcome! The patron saint of this thread is scienceofsharp.com but obviously nobody expects better than USB microscope.

Both edge-on and bevel snapshots are valuable. If possible, videos should show a full rotation from bevel to edge to opposite face so we can see the convexing.

Spousal Guidance Note: At first she may think “what? Yet another wasteful hobby expenditure” but you can quickly change her mind by magnifying a pimple, mole, hair follicle, or other engrossing cosmetic feature. Then you will have to get another scope for yourself.

 

[mengwong]

To start you off, a compilation of past threads involving microscopy

https://www.kitchenknifeforums.com/threads/microscopes-for-edge-inspection.63543/
https://www.kitchenknifeforums.com/...-sharp-to-paper-towel-sharp.63779/post-976615
https://www.kitchenknifeforums.com/threads/daily-sharpening-pics.55930/post-923270
https://www.kitchenknifeforums.com/...microscope-with-a-lit-mechanical-stage.52975/
https://www.kitchenknifeforums.com/threads/freehand-sharpening-with-microscope-pics.43770/
https://www.kitchenknifeforums.com/threads/microscope-to-take-pix-of-blade-sharpening-steps.28870/

 

[mengwong]

Someone I was speaking to on the forum used the term "cuts" angry, and upon reflection, that is a meaningful term. The edge feels toothy, and bites through tomato and pepper skins really easily. And it does offer decent food release.

Today I took a close look at a post-spa 210 TF Denka.

Microscopy confirms toothiness of the edge: note visible micro-serrations. In any other knife these would be considered micro-chips, and hurt performance. But on this knife they help: we get clean cuts through paper towel without hanging up. Yes, the cut is not as surgically smooth as on a uniformly keen 16k edge, but boy, does it go.

Images are snapshots from a rotation around the edge. Scale: approx 2.3mm wide, ruler shown.

 

[rob]

Nice and Toofie.

 

[blokey]

Today I took a close look at a post-spa 210 TF Denka.

Microscopy confirms toothiness of the edge: note visible micro-serrations. In any other knife these would be considered micro-chips, and hurt performance. But on this knife they seem to help it: we get clean cuts through paper towel without hanging up. Yes, the cut is not as surgically smooth as on a uniformly keen 16k edge, but boy, does it go.

Images are snapshots from a rotation around the edge. Scale: approx 2.3mm wide, ruler shown.

Very interesting

 

[tostadas]

Today I took a close look at a post-spa 210 TF Denka.

Microscopy confirms toothiness of the edge: note visible micro-serrations. In any other knife these would be considered micro-chips, and hurt performance. But on this knife they seem to help it: we get clean cuts through paper towel without hanging up. Yes, the cut is not as surgically smooth as on a uniformly keen 16k edge, but boy, does it go.

Images are snapshots from a rotation around the edge. Scale: approx 2.3mm wide, ruler shown.

Is that a freshly sharpened edge?

 

[mengwong]

Is that a freshly sharpened edge?

I haven’t sharpened it since I got it, and the seller hadn’t either since the spa, so only a few meals on the board I would guess.

 

[mengwong]

For science, I could refine to a keen apex with no microchips, then review after some use to see how the edge evolves. Does it retain tooth? Does the chipping create fat watermelon valleys or keen saddle-points?

I can also put my BNIB 240mm under the scope. Stay tuned…

 

[ITKKF]

I would suggest together with pictures to include zoom factor used too.

 

[mengwong]

I can also put my BNIB 240mm under the scope.

TF Denka 240mm BNIB.

Video of apex rotation:

This video shows more “convexing” of the right face – more distinct bevel angles, at any rate – and then the flatter ura on the left face making it a righty bias.

My scope has two zoom levels. In the images below, from a different spot on the edge, we begin zoomed out; then over two shots of the bevel grind I zoom in and remain zoomed in for the apex shots.

The apex is much keener, less toothy than the more well-worn 210mm.

 

[mengwong]

Nano-Hone NL-8, two zoom levels

 

[Martyfish]

I made a microscope related post yesterday and missed this thread, so here is a cross post seeing as it is relevant.
Micrographs of my Yoshikane Bunka

 

[mengwong]

I hope to see more from you! That Dino-Lite is impressive.

 

[mengwong]

Homi Kajiya duo of santoku and nakiri. Under the scope the waves of lacquer look like bevels. Sharpening with Arashiyama 1000 sees wisps of lacquer abrading off. Actual burr also shown.

 

[Martyfish]

Cross post to some micrographs of various surface finishes on the same blade:

https://www.kitchenknifeforums.com/threads/complete-makeover-of-a-shibazi-208-2.65317/post-1018317

 

[mengwong]

Human forefinger shortly after picking up a Naniwa A-902 stone holder by the bolt threads

 

[mengwong]

The correct tool for the job is called a "spudger". But when all you have is a kiridashi

 

[deltaplex]

Just putting a bevel on a credit card (or other similar thickness plastic stock) works very well for working in between tightly fit plastic/glass components.

 

[mengwong]

OOTB edge, 180mm MagnaCut from @MSicardCutlery



Subsequently deburred/refined on JKI green diamond resin 6000 plus pasted strop; now cuts curves in paper towel.

 

[MSicardCutlery]

Nice! I think I just went up to a 1200 grit or a 2k plate on that one.

 

[mengwong]

Decided to refine the edge on the 205mm MagnaCut passaround. See linked post for video:

This edge is OOTB, post-thinning I believe

Tried to maintain the post-thinning zero-ish grind; raised burr on JKI 6k diamond resin uneventfully:

Kippington deburred; microbeveled to bright line apex:

then diamond stropped to dim line. (Reduced reflections indicate a keener apex.)

Goniometry and BESS to follow.

 

[Genghis_F]

Decided to refine the edge on the 205mm MagnaCut passaround. See linked post for video:

Tried to maintain the post-thinning zero-ish grind; raised burr on JKI 6k diamond resin uneventfully:

View attachment 271124View attachment 271125View attachment 271126

Kippington deburred; microbeveled to bright line apex:
View attachment 271160
then diamond stropped to dim line. (Reduced reflections indicate a keener apex.)
View attachment 271159
Goniometry and BESS to follow.

Can you put up a picture of your microscope set up?
I have one but my lighting sets up a lot of glare
I can’t get that dark field background

 

[mengwong]

Can you put up a picture of your microscope set up?
I have one but my lighting sets up a lot of glare
I can’t get that dark field background

Excellent images. What are you using for a microscope? And, just as important, for lighting? It looks like a really good setup.

Sharpen freehand, microscope freehand. Usually I'm holding the knife with the right hand. If I want to change the background I move it between the (dark) stove area and the (light) countertop.

Knives are the 205mm MagnaCut Passaround and the entry level 210mm Sakai Kikumori Nihonko.

BESS scores on both were around 120 on the spool, 90 on the disposables. JKI 6k diamond resin. I was hoping to get under 100 on the spool. But they both shave and cut curves in paper towel so I'm satisfied.

Microscope is in the "1000x", "4K", < $100 category of gadget connected over self-hosted wifi to a display app on my phone, bizarrely named "wifi check".

 

[mengwong]

First sharpening of the cute mooncake knife, aka
https://knifejapan.com/fukamizu-hamono-kuri-no-kawamuki-75mm-shirogami-2/
OOTB factory edge modulo a couple of mooncake slices and citrus, probably where the rust started

Shirogami 2 taken to a zero edge on Arashiyama 1000: foil burr with square serrations

Kippington deburred and microbeveled with SG16000, just a couple light strokes, to shaving sharp, estimated BESS 120.

I have a feeling this edge is not going to survive its next Mimolette.

 

[mengwong]

I think somebody in the household may have tried to take the Magnacut passaround knife through chicken bone. Tiny chips barely visible with the naked eye, will probably sharpen out over time. Interesting to see actual failure with this supersteel. Scratches are from 6k JKI diamond resin.

 

[mengwong]

A couple weeks and a couple more chicken bones later, I scoped the entire edge, then touched up on SG1000 back to shaving sharpness. It took less time than I expected, maybe 10 minutes total stone time at medium pressure, extra attention paid to deburring evenly. Even when I heard the knife going through the carcass I didn’t say anything – I wanted to see how MagnaCut would fare when treated like a cleaver. Turns out at 15 degrees it still does ok!

Before: some edge deformation and chipping visible.


After: touched up successfully on SG, no diamond


The previous craters, at end of session

Mind, this is all under very high magnification. To the naked eye there are only a couple of glints on the edge

 

[mengwong]

This just in for ARM2024:

Shibazi F208-2 205mm

OOTB wire edge went through paper towel well enough… then two slices against the side of a chopping board folded over the burr and that was it for the paper towel test. Edge visibly unkeen:

Bright line visible, implies >1micron

SG16k to the rescue! Approx 10 edge-leading strokes per side at the manufacturer-recommended 11°. Black bits are mirror polish.

My angle control was better in some places than others. SG16k eating factory grind, convexing shoulders:

Reduced reflection suggests 1micron apex achieved here and there.

 

[1315]

Great stuff, thanks for taking the time to post.
Question: have you researched the microscopes much? How many have you tried? Would you recommend the one you linked above, or do you think more power is necessary? If appreciate and comments on that hardware you might have.

 

[mengwong]

I have only a cheap USB/Wifi scope. I have heard good things about Dino-Lites.

Whatever @Deadboxhero has is probably as good as it gets short of SEM.

can see the ~2-4μm carbides at the edge

 

[mengwong]

The 37g Deejo

comes with a surprisingly decent factory edge. I’ve seen worse!