Magnifying glasses.

H

_habit_

Joined
Oct 14, 2006
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I've read some posts saying that people should use magnifying glasses to be able to examine the blade when sharpening, and I'm wondering things like: How much they cost, how much they need to magnify things, and all questions like that.

Now, on another note, I have a magnifying glass in front of me that is used for fixing glasses (kind you wear on your face), and it seems to magnify about 3-4X by my guess, is that adequate?



Looking at my own knife under the magnifying glass, I think I need to "hone" the edge with a sharpening steel, as it doesn't look evenly sharpened (it's a brand new Kershaw Leek, barely been used, and has not been "honed" so far).
 
Howdy,

I like to use a 5x. But a 3X should work.

I don't think using a magnifying glass is a requirement for sharpening. I just find that it helps me, especially when working on a new blade. I find that some of my blades, even the ones that are sharp out of the box, have fine grind marks left on the bevel. I can see them if I use a lens. I think the edge is more stable once the grind marks have been removed by sharpening. But that's purely opinion. I have no proof.

A lotta folks been sharpening just fine for generations without using a lens. (But a lot of those generations didn't have to worry about machining marks. Because machining the bevel is a fairly new process when compared to the duration of the history of the blade.)
 
knarfeng said:
Howdy,

I like to use a 5x. But a 3X should work.

I don't think using a magnifying glass is a requirement for sharpening. I just find that it helps me, especially when working on a new blade. I find that some of my blades, even the ones that are sharp out of the box, have fine grind marks left on the bevel. I can see them if I use a lens. I think the edge is more stable once the grind marks have been removed by sharpening. But that's purely opinion. I have no proof.

A lotta folks been sharpening just fine for generations without using a lens. (But a lot of those generations didn't have to worry about machining marks. Because machining the bevel is a fairly new process when compared to the duration of the history of the blade.)
Click to expand...

I'm not entirely sure what grind marks are, but my blade pretty much looks like crap... there's a small... don't have a ruler here, but I would say 1 cm part on it that looks different then the rest of the edge!

I'm not entirely sure I could get a clear picture of the blade under the magnifying glass, but I'll try later.



And I guess I wont go out and buy a new one :) (still have to get some paracord though, since I want to start making some lanyards)
 
I use the 15X lighted loupe from www.leevalley.com costs $22.50 plus shipping. I agree that you don't "need" a loupe for sharpening, but it sure makes it easier to see what you are doing. Also lets you see interesting things occuring along the edge ie. the "tearing" of a D2 edge sharpened to about 10 deg. included.
 
A loupe can be used to insure you are sharpening to the extreme edge, especially in combo with a sharpie marker. I had a situation recently where I couldn't raise a burr on a kitchen knife. I had marked the bevel with a marker and my strokes on the bevel removed all the visible marker quickly, but still no burr. I looked at the edge with a 10X loup and could see that there was a very narrow micro-bevel that was still black. I couldn't see it without the loupe. So I went back to coarse grit and wiped the smile off its face.

You can also use a loop to see burrs, but I haven't done much of that.

Here is a good 10X one for $14 that was recommended on the forums in the past. I like it a lot.

http://www.ambericawest.com/loupe.html

The more powerful lenses get harder to use since the focus field becomes very shallow. I haven't tried anything more than 10X, but I might some day. I have a 6X from Sears that works OK too.
 
Well, if I'm regularly using a fine/x fine I wouldn't need to worry about micro-bevels would I?
 
matt321 said:
A loupe can be used to insure you are sharpening to the extreme edge, especially in combo with a sharpie marker. I had a situation recently where I couldn't raise a burr on a kitchen knife. I had marked the bevel with a marker and my strokes on the bevel removed all the visible marker quickly, but still no burr. I looked at the edge with a 10X loup and could see that there was a very narrow micro-bevel that was still black. I couldn't see it without the loupe. So I went back to coarse grit and wiped the smile off its face.

You can also use a loop to see burrs, but I haven't done much of that.

Here is a good 10X one for $14 that was recommended on the forums in the past. I like it a lot.

http://www.ambericawest.com/loupe.html

The more powerful lenses get harder to use since the focus field becomes very shallow. I haven't tried anything more than 10X, but I might some day. I have a 6X from Sears that works OK too.
Click to expand...

the Belomo loupe mentioned above is the best out there for the money. i had a "Five Elements" 10x loupe and thought that was fine. then i saw others talk about the Belomo and bought one. what a difference! much larger and crisper, and also extremely well-built. highly recommended. thanks to those who pointed me in the right direction.:)
 
_habit_ said:
I'm not entirely sure what grind marks are, but my blade pretty much looks like crap... there's a small... don't have a ruler here, but I would say 1 cm part on it that looks different then the rest of the edge!
QUOTE]

I call then "grind marks". You might call them "machining marks". When I look at a new blade under a lens I often see ridges that are perpendicular to the blade edge. I consider them to be left over from the machining process of creating the edge bevel. Their presence implies that the surface is wavy instead of smooth. When taking something down to a fine edge, the impact of such a surface imperfection is magnified. I consider that the steel at the edge of that wavy surface is weakoned because it is not a uniform thickness. (Again, my estimation of the result. I have no hard data to back me up.)

YMMV as to whether they are there on an individual knife. I saw them on both my Native III and my Junglee Marshall. They were so bad on a Gerber EZ-out that I could see them without a lens. I did not notice any on my Benchmade Ascent, but I sharpened it out of habit without looking.

After proper sharpening the marks are no longer there. Many folks have talked about how edge retention of a blade improves after a couple of sharpenings. I have read several posts that attribute the improvement to a difference in the heat treat of the edge vs. heat treat of the rest of the knife. I cannot comment on that. But I can comment that many knives have these fine striations out-of-the-box that disappear after sharpening. My suppostion is that these fine machine marks may actually be what is causing the degraded performance of the original factory edge. But it is mere suppostion based on observation. So, I check all new blades for striations and sharpen any blades that have them. In the words of the old chicken soup joke, "It couln't hurt".

Knarfeng.
Click to expand...
 
I have worn an Optivisor for over 25 years. I got the idea from an old tool and die maker I used to do business with. I use this one:
http://www.lssproducts.com/prodinfo.asp?number=DA-5
When sharpening it gives me the extra detail that my eyes do not show anymore. They are comfortable to wear and I keep it so I can look under it or look up a little and through the visor.
 
I use a little 10x loupe made for looking at photo negatives. you can find them at most camera stores - pretty cheap.
 
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