04-18-2018, 06:46 PM (This post was last modified: 04-18-2018, 07:01 PM by grepper.)
Mr. EOU uttered, "its not really clear what $1200.00 is going to buy you from an optical standpoint because most of the metallurgical scopes are much lower magnification."
Not sure where you came up with that idea Mr. EOU. I think you may be confusing a dissecting and metallurgical scopes. Dissecting scopes natively are 40X-50X or less and with a multiplier can get up to 100X or so. Metallurgical scopes go to 2000X or higher.
Additionally, both good dissecting and metallurgical scopes have much higher quality of glass than cheapo USB scopes do, which results in greatly improved image quality and metallurgical scopes come in both bright and dark field. The difference in image quality between a good quality metallurgical microscope and cheap $100 USB scope is remarkable.
Comparing a decent metallurgical scope and the image quality it produces with a $100 or less USB scope is like comparing a Brownie camera with a with a Nikon D850 dslr. They both take pictures but other than that they have little in common and the images they produce are dramatically different.
Additionally, good quality scopes have sturdy frames with X/Y mechanical stages to precisely hold the subject allowing for precise focusing. Nothing at all like the hair pulling freak show of trying to focus USB scopes with the crap for stands that they come with.
Much better image sensors are available for quality microscopes too. Usually USB scopes range from 1.2mp to 5mp, and the sensors are not very good to begin with. 10mp cameras with quality sensors are not uncommon in good metallurgical scopes, which produce far superior image quality with considerably greater detail than budget USB scopes do.
Metallurgical scopes also are available in inverted versions where the optics are under the stage, allowing for large and oddly shaped subjects to be studied that normally would not fit in the available working distance of a standard design scope.
Metallurgical scopes designed to study metallic surfaces have excellent achromatic optical systems and polarizing filters to reduce that annoying rainbow effect of light reflected of shiny surfaces that completely obliterates detail and makes it impossible to even tell what you are looking at.
When it comes to cameras, binoculars, telescopes and microscopes, quality glass is expensive. It's another one of those cases that you really get what you pay. Prices for a decent metallurgical scope start at about $1K. Here's an example:
04-18-2018, 06:54 PM (This post was last modified: 04-18-2018, 06:58 PM by EOU.)
Sorry Rick but can't blame this one on Mike. I (Dave ) posted the EOU reply. I saw all the conversation and pictures of microscopes and thought that was where we were. I guess that I better just stick to my RS232 comm programs. As I said, we have a stage here that we constructed for our scope. I'm going to hand this off to Harley or Mike tomorrow and see if they can take and post a picture tomorrow.
Now I just see that Grepper posted. I think I better stop covering the Exchange when everyone else is gone.
Gripping the knife from the handle allows adjusting the blade angle. I suspect that you are sort of limited in working distance so any type of adjustable angle vice would have to be rather flat, but by gripping the knife by the handle the vice is off to the side of the scope, and the scope may be place on a raised surface so only the blade in in the working distance of the scope.
Man, I search a lot and it's about impossible to find images from a metallurgical microscope. It's easy to find images of a scope, but very difficult to find sample images taken by them.
Just to give you an idea, this image was taken with an AmScope metallurgical microscope:
And "this image of a steel plate was captured using the Meiji IM-7200 inverted metallurgical microscope and the Motic MC2000 microscope camera."
Gripping the knife from the handle allows adjusting the blade angle. I suspect that you are sort of limited in working distance so any type of adjustable angle vice would have to be rather flat, but by gripping the knife by the handle the vice is off to the side of the scope, and the scope may be place on a raised surface so only the blade in in the working distance of the scope.
Thanks for the on target reply. And thanks for the very practical idea for use of small vises.
I actually have quite a bit of head space with this microscope. I got one with a tall column and a long boom so I could bring in barn boards and other interesting objects for examining growths and other things on them. Haven't had occasion to use the boom yet. I may have to find a lower table to put the scope on as I have to raise the head fairly high for some objects. Also, a major justification was so my granddaughter could see things, and she has to stand on a chair to see.
I also have a couple sizes of drill press vises, one small, one medium, so it may not matter if I find that angle plate, although I think it will fit.
I tried out the smaller one on a Kershaw folding knife. I like how easy it is to align and adjust the position, being able to view the bevel and the edge at different angles. I'm thinking I don't need to worry about finding that angle plate, at least for knives. No microscope images to share, but I was appalled at the apparent condition of the edge, even though it tested fairly sharp.
I hope others will share their methods and devices.
Wow Mr. Grepper, those look like quality images to me. I wish I could do that.
This is obviously over my head presently, but I checked in with our friend Mr. Max, who got a handful of the mini-micros a while ago. He is using them with satisfaction as well.
Mr. Rick, I like your original adjustable angle plate though. Seems like getting the right angle for the light is important. A nice jig like that might even make it possible to use a pos USB.
If I were trying to fix the knife to the angle plate, I would use "Glass Setting Butyl Tape" like THIS
It's almost dangerously sticky, so it has a wide range of uses. There are less sticky versions of this type of stuff that would probably work too.
"Mr. Dave, I'm going to go ahead and blame it on Mr. Mike anyway." The buck stops here Grepper.
Here's the optical fixture that Dave was referring to. It's pretty basic and magnet centric.
The scope stem is mounted in a slip-fit fixture with a locking screw. The base of this small fixture has a magnet screwed to it's base so the magnet can slide on the plate and the plate that the magnet is stuck to can slide back and forth as well. Once again, the knife is secured to the upper plate via a thin flat magnet so it can be positioned (XY) however you like.
If we want to look at an edge "edge-on" we introduce another vise (magnetic base as well) as in photo two. If we want to look at the edge at a particular angle we use an angle adjustable vise. In our opinion, the microscopic knife world needs an XYZ adjustable stage for the knife and a camera whose focus and lighting level can be adjusted remotely via a com link to the PC. As you know, everytime you touch one of these cameras to make an adjustment everything goes to "H" in a handbasket. The stage is available and don't doubt that the camera is as well. Just a matter of where you want to spend your money.
About 6 or 8 years ago, we found the 35x "mini-microscope" on Amazon for about $5 or so. They worked pretty well, but needed the LED light. A year or two ago, the 35x was replaced with a very similar 60x, which are available on Amazon right now for $3- $10, depending on where you get them.
These mini-microscopes are as close to perfect as anything I've come across. The lenses are large enough that they don't need the on-board LED. They are incredibly easy to use- as easy as a normal 10x loupe without a light, and 60x is enough to see Everything.
I'm not exaggerating at all when I say these are a game changer to me. I literally use one every time I sharpen a knife. They allow me to Closely inspect both sides of a 4" blade in seconds. Nothing...Nothing I've ever seen comes close- in magnification or ease of use.
Type in "60x mini-microscope" on Amazon to find one. Like I said, you will find them available from multiple sources. I've ordered 3 times from different places and gotten identical products, in identical packaging.
All,
I have put a plug in for the little 60X hand microscope that Mark posted about. Sounded kind of hokey, but I bought one and am finding that it is everything Mark cracked it up to be. I has surprisingly good optics for such a cheap price. It is so small, it is easy to carry in a shirt pocket and it doesn't even crowd my reading glasses.
As Mark says, you can see everything on an edge. I've used it for inspecting edges on drills I've sharpened using my Tormek. I've used it to locate slivers too small for my Optivisor (10X) to find. Just yesterday, I was bothered by something embedded in the white poly sheet in one of EOU's SharpPads. It was scratching knife surfaces. I found it using the 60X and used it to view it while I pried it free. No more scratches. I have also inspected the cutting points on carbide insert lathe tooling in a way that I never could before.
While this little thing is not going to replace a dedicated microscope for higher quality viewing and taking photos, since getting one, I have not taken any edge to my microscope for viewing during the sharpening process. The 60X has satisfied all my needs. It is not possible to use it for anything but real-time viewing and I've had one friend who could not figure out how to look through it (but they didn't really try very hard).
It has an adjustable focus and a clear plastic shroud that can be used as a standoff for locating your focus range and sliding along an edge, keeping it in focus. As Mark suggested, I put a drop of superglue on the barrel to lock it into position, at a position slightly too close in. The edge (or whatever) can be brought in to focus by rocking the unit back until it is.
I blew the first one I glued, too far out, so it is now pretty much useless. Fortunately, I have found it so useful, that I already had two more on order and they arrived soon enough.
I stow one in my BESS PT-50 Sharpness Tester kit and keep another on my workbench. I am about to go on a road trip to visit a friend and do a bunch of sharpening for him and his wife and I may not pack my dissecting microscope and use only this 60X unit.
It is small, only about 1.5" OAL, but it sure is handy.
