Microscopes for edge inspection

[1315]

There was a past post on this somewhere, and many dismissed using visuals for inspecting the edge. I used a little $30 usb microscope. I learned a ton looking at my edge, especially when compared to Andrei's perfect Markin edge! Wow! The Markin gave me perspective, and some ideas for improvement when compared to my edge work.

Anyway, I'm glad I bought it. My mistake was only getting a 2 MegaPixel resolution. You can snap photos when looking at edges through the microscope. If you then open them, then maximize the screen size, then zoom, you lose clarity very fast with only 2 MP and it's kinda worthless. The unit I bought says 1000x, but it's nowhere near that. I think it's more like 40x if zoomed, and if expanded on screen maybe goes to 50-60x but again, gets fuzzy before that point.

Attached is a photo from my first microscope effort so may not be totally efficient

Here is a link to my $30 USB microscope that links to my PC screen via usb cable, or to my android phone screen via wifi:
https://www.amazon.com/Microscope-S...&qid=1676004691&sprefix=usb+mi,aps,718&sr=8-5
My question: What microscopes do you have that you'd recommend, what power or features are important, what is the price, and from whom? Is it worthwhile to buy better resolution for knives than the $30 picture above?

Thanks for your opinions,
1315...out.

 

[Miyamoto Musashi]

There was a past post on this somewhere, and many dismissed using visuals for inspecting the edge. I used a little $30 usb microscope. I learned a ton looking at my edge, especially when compared to Andrei's perfect Markin edge! Wow! The Markin gave me perspective, and some ideas for improvement when compared to my edge work.

Anyway, I'm glad I bought it. My mistake was only getting a 2 MegaPixel resolution. You can snap photos when looking at edges through the microscope. If you then open them, then maximize the screen size, then zoom, you lose clarity very fast with only 2 MP and it's kinda worthless. The unit I bought says 1000x, but it's nowhere near that. I think it's more like 40x if zoomed, and if expanded on screen maybe goes to 50-60x but again, gets fuzzy before that point.

Attached is a photo from me scope, from my first microscope effort so may not be totally efficient
View attachment 224868https://www.amazon.com/Microscope-S...&qid=1676004691&sprefix=usb+mi,aps,718&sr=8-5
My question: What microscopes do you have that you'd recommend, what power or features are important, what is the price, and from whom? Is it worthwhile to buy better resolution for knives than the $30 picture above?

Thanks for your opinions,
1315...out.

I’ve seen something like this on Andrew Ren’s instagram (@xtol.ren). It may be more suitable for kanna though. Here’s a post that shows some of the optics he uses.

 

[ian]

There was a past post on this somewhere, and many dismissed using visuals for inspecting the edge. I used a little $30 usb microscope. I learned a ton looking at my edge, especially when compared to Andrei's perfect Markin edge! Wow! The Markin gave me perspective, and some ideas for improvement when compared to my edge work.

What did you learn?

 

[miggus]

I have looked into the same thing a few months ago, I can see the allure in knowing exactly what one is doing to the edge, and if there is a easy, affordable option out there, I'd still be very interested.

I asked on dpreview (digital photography forum) about this. I got quite a bit of helpful suggestions ranging from digital camera and phone conversion over to microscopes. Maybe there's something in there for you @1315:

https://www.dpreview.com/forums/post/66470345
If you're interested in background info, you can find a great explanation with examples about the challenges of using optical microscopes for evaluating edges: Science of Sharp - Optical vs Electron Microscope

I'm not saying it can't be done, but after reading Larrin's article, I decided that even results he got with lab-quality optical microscopes were modestly helpful at best. The electron mic photos are absolutely perfect, but I just don't have the countertop space to place one of those here.

With optical microscopes, it's not so much a problem of magnification, but also one of tackling threedimensionality and reflections of light. If one were willing to pursue this, i'm sure that a solution can be found. But I personally decided it was not worth the effort, both in money to spend on equipment and in time to figure out how to get this to work.

And yeah - please let us know what your findings and conclusions are.

 

[captaincaed]

I have the same or similar model, and higher resolution may be possible. Are you using the grey barrel adjuster as zoom or focus?

 

[mengwong]

In my experience, besides showing microchips,

an optical microscope is valuable when used to reveal edge-on reflections from an imperfect apex.

3.x millimeter scale.

 

[1315]

Captainc,
I drop the lens as close as possible, so it touches the edge. Then the grey dial to focus.
Then snap a pic, open in photo manager, expand to full screen on my laptop, tgen click to enlarge picture size.

 

[captaincaed]

Captainc,
I drop the lens as close as possible, so it touches the edge. Then the grey dial to focus.
Then snap a pic, open in photo manager, expand to full screen on my laptop, tgen click to enlarge picture size.

On mine the barrel adjuster was the zoom, and focus came from adjusting distance between the lens and blade. Maybe that will work for you?

It took me a few tries to figure it out.

 

[captaincaed]

FWIW I like this one for the adjusting knob to help with focusing at high magnification
https://www.amazon.com/Jiusion-Micr...7DQM237K&psc=1&ref_=pd_basp_bia_rpt_ba_s_1_sc

 

[1315]

 

[cotedupy]

an optical microscope is valuable when used to reveal edge-on reflections from an imperfect apex.

^ This was my first thought ^. I imagine it could be quite an interesting way of learning more about wire edges and deburring.

TBH I'm not sure I could ever be faffed with looking at an edge under a USB scope. Though of course I do enjoy whiling away an hour or three looking at the surfaces of whetstones with one. But then who doesn't eh!

 

[1315]

The last 2 photos are of the same edge.
1. From the first photo, I learned "maybe I should not have asked!" Seems there is a blem near the edge. Sabi wabi!
2. Both pics above are 4K finish. The bottom pic, I paid attention more to parallel strokes, consistency, and lightening/tapering the pressure as I finished the progression. Much better! Next, on to 8K...

 

[Rangen]

Those are photos of the same edge.
1. From the first photo, I learned "maybe I should not have asked!" Seems there is a blem near the edge.
2. Both pics above are 4K finish. The bottom pic, I paid attention more to parallel strokes, consistency, and lightening/tapering the pressure as I finished the progression. Much better! Next, on to 8K...

Yes, this is exactly why I have gone way too overboard on magnification devices. It's like hiring a little devil who says into your ear: "You still suck at sharpening."

Not that pleasant, maybe, but a great cure for arrogance.

 

[1315]

""Not that pleasant, maybe, but a great cure for arrogance.""

EXACTLY!! Its really messed up that ill sleep better because i know i have a uniformed scratch pattern.

 

[1315]

I recommend looking carefully at the flatness of the apex on this progression:

Pre-microscope 4k Shapton Glass. I'm a rookie sharpener, and didn't spend enough time (or lighten pressure) as I progressed on the finer grits. Haphazard scratch pattern:

Post-microscope inspection with Shapton Glass 4k, more consistency and better progression, tapering off on pressure:

Post microscope 8k shapton glass:

And what have I learned?:
That the three-finger edge inspection is a real thing.

 

[blokey]

Darn I remember when I was a kid I always want a microscope, even a toy one to just play around, but they are just way too expensive, now you can buy them for the cost of a vic chef, what a time we live in.

 

[mengwong]

Imperfect edges but still <100 BESS.

 

[1315]

What stone or film did you finish with?

 

[mengwong]

SG16k then stropped on leather with old 1k micron paste. Details here: anyone have a BESS tester??

The SK went through a whole polishing progression then a week of sedate rusting: Daily Sharpening Pics

 

[Rangen]

Imperfect edges but still <100 BESS.

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

 

[mengwong]

What are you using for a microscope? And, just as important, for lighting?

Thank you! My USB/wifi microscope has integrated illumination, it’s like a ring of maybe 12 LEDs with adjustable brightness. I usually geek out at night so finding a dark background is easy.

My “4K” scope should be about $40 on Amazon.

 

[rickbern]

Just saw this on a photo site, thought you guys might be interested

https://fstoppers.com/macro-photography/turn-your-iphone-40x-microscope-heres-how-651854

 

[The Forest Ninja]

Just filmed a brand new utility blade.

 

[Deadboxhero]

CPM 20CV, can see the ~2-4μm carbides at the edge