Some homemade micrographs

I can do microscope movies, but turning the blade real time would throw it out of focus. There is software that can combine images for greater depth of focus, like "combinez" or a slicker commercial package called "Helicon Focus" (http://www.heliconfilter.com/pages/focus_overview.html )

I did try playing with "Combine-z5" and put together 4 images of the diamonds on a DMT plate focusing for maximum sharpness at 4 different levels and got this:

Which isn't too bad, considering that it was my first attempt without reading the documentation (and hadn't figured out how to get rid of the processing artifiacts, which are the distortions on the right and bottom of the image)
 
There is the 60-100x one here too. That uses a smaller LED to illuminate, plus both lenses are smaller in diameter. It is fine for looking through; I mainly chose this one because it is easier to photograph though.

I secure both the scope and the camera to a board such that the lenses are at the same level. I step up the camera with some coins. I put the camera on manual and use the following settings: zoom out to max, ISO 100 (default), focus at 0.5m, incandecent colour adjust (the LED if fairly yellow), sharpen, open up apature (5.2), and adjust exposure time as necessary. I focus the image using the knob on the microscope. The image usually requires brightening later, and I resize it smaller because the detail is not there anyway.



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That's a pretty detailed picture of the diamond particles, Yuzuha. What grit is that particular one?
 
Okay, here are some edge on shots with 2 SAK blades, the VG10 Caly Jr, S30V Military, and ATS-34 AFCK. Pinpoint reflections from round teeth are visible in all the edges. It is hard to maintain one's objectivity, but the VG10 does look more spoty than the S30V. The ATS-34 edge looks the least defined here, although the high reflectivity in the middle section might not be an accurate representation.



Same picture 100% bigger
 
Those kinds of pictures, edge on, are very informative during cutting work as it reflects significantly the strength of the steel. The deformation is usually much more distinct looking into the edge rather than the side. You can also clearly see the edge thicken as it wears. Chips however tend to be better represented from side visuals.

-Cliff
 
Hmm, my S30V paramilitary has a handful of small chips, and my Boye cobalt has some crazy gouges on the edge bevel-may have been leftover from the 600 DMT. I'll try and get some shots for comparison, even with stropping on CrO, the edge of the Boye is quite uneven at this magnification.
 
You guys are going to give me the bug by showing these pics. :) Anyone think of recording pics showing an edge getting dull? Kind of like a pic of a sharp edge, then a pic after 20 cuts in something and so on?
 
db said:
Anyone think of recording pics showing an edge getting dull? Kind of like a pic of a sharp edge, then a pic after 20 cuts in something and so on?
Click to expand...

Yes, in fact I showed you links to this many times. There are several guys doing this with plane blades under relatively high magnification, they actually measure the wear to determine blunting.

-Cliff
 
How about a link from you again then. You trying to start another arguement with me Cliff?
 
It is in the main reference page I wrote on blade evaluation db which I have referenced to you specifically several times. There is also of course the work done by Landes who even used chemically treated samples to show the specific carbide/grain structure and the massive amount of work done on tool steels in this regard to determine both the amount and type of wear papers you can find in materials journals. These are on subjects like how the secondary and primary carbides react differently in HSS and how to optomize heat treating for specific tools such as rollers because you don't always want simply maximal wear resistance as it can lead to premature surface degredation. There is also the work done by FuriTech on kitchen knives which show freshly sharpened / worn knives. Sal Glesser and Jerry Busse have also observed edges under magnification, it is one of the reasons Busse switched to high toughness steels because he saw that hard use blades didn't wear smooth they tended to deform/fracture as the primary method of failure.

-Cliff
 
Cliff thanks for provideing the links. Now if I could only find them.
Is that the same way you've showed them to me many times?
 
Cliff Stamp said:
Quote:

Originally Posted by db
Anyone think of recording pics showing an edge getting dull? Kind of like a pic of a sharp edge, then a pic after 20 cuts in something and so on?

Yes, in fact I showed you links to this many times. There are several guys doing this with plane blades under relatively high magnification, they actually measure the wear to determine blunting.

-Cliff
Click to expand...


Cliff Stamp said:
Ref :

http://www.physics.mun.ca/~sstamp/knives/blade_testing.html

I have a bunch of research papers to add on various topics but they are not on line so they will just be references.

-Cliff
Click to expand...
Alright then. Thanks for all your help
 
kel_aa said:
That's a pretty detailed picture of the diamond particles, Yuzuha. What grit is that particular one?
Click to expand...

DMT 120 grit XX-coarse diasharp plate. The problem with them is that light shines through them and creates a little pool of light around the base as well as reflecting off the faces, which sort of messes up the exposure. I have a much nicer photo at lower power that looks like they're floating in a pool of molten solder.
 
Cliff Stamp said:
Yes, in fact I showed you links to this many times. There are several guys doing this with plane blades under relatively high magnification, they actually measure the wear to determine blunting.

-Cliff
Click to expand...

Yeah, I love Brent Beach's page. He gets some nice shots out of that QX3 (others have taken some pretty nice shots with the updated QX5 too).
 
Yeah those two guys have a nice body of work in many respects. Some of it is what you would expect like the HSS blades have a many to one advantage but others are really surprising like A2 having a relatively low edge stability compared to D2. That's kind of hard to explain based on the structure of the steels but that is what the results show consistently. I'd really like to see the internal structure of those plane blades. A2 is one of the steels commonly praised by makers such as R.J. Martin as being especially good for chisel grinds.

-Cliff
 
Couldn't get the camera to work, I may be able to jerry rig something this weekend. I did use the magnifier to check out what happened to my paramilitary when cutting cardboard. I got the edge fairly even with a 40 micro on the SM, only 3 noticeable chips at 100X, and started to slice. After 40 slices, what I can manage on one side of a cardboard tray, I checked again. I had picked up 5 more chips. At 200 cuts, I stopped counting at 15 chips, but it was over 2 dozen easily. These were still very small, the knife could still shave with very slight abrasion, and half of them were removed with 5 passes on fine spyderco and the same number on loaded leather. The rest are little more than slight deviations in the almost straight line of the edge, except for one little semicircle near the tip.
 
hardheart said:
I got the edge fairly even with a 40 micro on the SM, only 3 noticeable chips at 100X, and started to slice.
Click to expand...

Is that 100X on the Radio Shack as they are quoting area magnification to make the number bigger. The linear magnification is the square root, so 10X on full magnification. It is normal for the edge to not form clean and instead be chipping under magnification? How large are the chips and what is their nature (shape).

At 200 cuts, I stopped counting at 15 chips, but it was over 2 dozen easily. These were still very small, the knife could still shave with very slight abrasion, and half of them were removed with 5 passes on fine spyderco and the same number on loaded leather.
Click to expand...

Does VG-10 behave in a similar manner, chipping as the main source of blunting?

The rest are little more than slight deviations in the almost straight line of the edge, except for one little semicircle near the tip.
Click to expand...

What does the first of that sentance mean exactly?

-Cliff
 
Inspired by Hardheart, I tried something similar. I used a Vic Tinker large blade and a few pieces of cardboard around two feet long. I could pretty smoothly cut through them using the hole edge. I checked the edge with a small hand magnifier. After 20 slices nothing really different at all After 40 cuts I could tell the very edge was off center just a hair, a little wavy. After 60 cuts the edge was pushed to one side and was a little wavy. It is still sharp and I tried to feel it and couldn’t with a finger nail. No chips at all. I’m guessing I can easily double this amount of sliceing. I didn’t try any resharpening or realining of the edge. I may wait until I have some more cardboard and see what happens with more sliceing. . Sliceing was against the ridges in the cardboard, and fairly fast. The blade even warmed up doing the sliceing. Slices started at the tip and ended at the heal. Trying to resist geting a scope. :)
 
Cliff Stamp said:
It is normal for the edge to not form clean and instead be chipping under magnification? How large are the chips and what is their nature (shape).
Click to expand...

Well, I just got the little scope, and haven't had the paramilitary for a terribly long time, so I don't have a reference for it. But, as I noted in another thread about S30V burring, this blade burrs very quickly and easily. After I received it (dull, unable to slice newsprint) I sharpened by first cutting with the D8XX, then cleaning that up with fine SiC, then the sharpmaker med & fine, and finally loaded leather. I have raised and removed a burr through all steps a few times on this blade, including burrs from the fine SM. I would hope I'm not dealing with poor steel at the edge at this point.

I am a little surprised by the chips, as they are somewhat significant under magnification, semicircular in shape. I ignored slight irregularities in the edge, those that you might imagine as appearing similar to a line drawing where you begin by using a ruler as a straightedge, and then somewhere along the way you remove it and try to continue the line as best you can. Keeping track of these would be difficult, and they could be dependent on the way the blade was profiled as much as how it was sharpened. But these chips are distinct, not something I lose with a slight shift of focus as I move along the edge viewing. I may be stressing the edge a bit on the corners of the SM rods, but I finish on the flats and then move to the leather.

Does VG-10 behave in a similar manner, chipping as the main source of blunting?
Click to expand...

Sorry, I don't currently have a VG10 blade. But I have just gathered up 10 blades that I will do cardboard cutting with-

2 BM balisongs, one in D2, the other should be 440C or 12C27 (will check to make certain)

my M2 Rittergrip (which, under the same magnification, has what I would call a perfect edge-no chips, and as straight an edge as I can see)

G10 Cara Cara

CRKT S2 (ATS34)

CRKT Partner (AUS6, I believe)

Sorsakoski balisong style folder (Finnish, guessing 12C27),

a necker by LR Harner in CPM154

some old stainless Chicago Cutlery chef's knife I brought up to sharpen

and that little knife made from a bandsaw blade I used to hack on those sticks.

What does the first of that sentance mean exactly?
Click to expand...
Just that I didn't get the edge as straight as I could have. I reduced almost all of the chips to where they were just slight 'wiggles' in the edge at most. A little more time on the fine stone will remove them completely, I just wanted to see what would happen to the edge with just a handful of passes on the lower grit abrasive after the cutting.

I will only really be able to simply inspect each edge for chipping, both during sharpening and cutting cardboard. I haven't established any measure of sharpness, or a corresponding way to determine blunting. I will make a matching number of cuts for each (going again with the para as well) just to see how the edges chip, but I don't have any way of measuring how well they cut in comparison beyond just how it 'feels'.

And I am really gonna want to get some pictures of this, so I will see who
I can bum a decent camera off of.
 
Cliff Stamp said:
Those kinds of pictures, edge on, are very informative during cutting work as it reflects significantly the strength of the steel. The deformation is usually much more distinct looking into the edge rather than the side. You can also clearly see the edge thicken as it wears. Chips however tend to be better represented from side visuals.

-Cliff
Click to expand...

Well, I tried a straight edge on shot of my Calypso Jr (zdp189) polished on 15k stone and 1/4 micron diamond paste, and didn't get much, even with a stack of 8 images processed for increased depth of field. You can see some little dust spots on the edge, but things are just too smooth to get much detail in a pure edge shot (and I had two halogen lights inches away from it too):


Here's a more angled shot of a Watanabe damascus petty at 1/3 the power of the previous photo:
 
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