what finish to put on edges?

FlyingMuskrat said:
So how sharp would you call a knife that can push cut straight down through newspring very close to where you hold it?
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A few years back I would have called it sharp, now I would call it burred, unless your newsprint is very different than mind. With optimally sharpened edges you can move out to a few inches. It also depends on how you cut it. Rotate the page 90 degrees and try push cutting. It will either get much harder or much easier as there is a grain to the paper.

In regards to the reprofiling, the primary grind was changed from low sabre flat to higher sabre/convex. The secondary edge bevel was mainly obliterated. I'd call it a reprofile of the primary grind.

-Cliff
 
Thom your the one who is doing the imspiring now. Very nice. I also refer to thinning the blade grind as reprofiling/reprofiling the edge.
 
The profile is what makes the difference between a drop point, clip point, sheepsfoot, etc. It's the shape of the blade in profile, ie from a side view. If you change a blade from a drop point to a clip point that is reprofiling the blade.

Some people talk about "reprofiling the edge" when they mean changing the angle. It just makes for confusion....
 
Thom I finally stopped grinding went ahead and put a 30 degree included microbevel just big enough to be seen. I like the knife, but it would not hold it's edge very well without the microbevel - I estimate the primary grind at about 10 degrees per side.

It cuts well. It is admittedly way uglier than yours. I got alot of scratches on the flat of the blade. Some have recommended sandpaper to make it look better. I may not even worry about it as this is a user.
 
You can usually spot a burr readily under magnification, even 10x, because one side will be darker as it is bent over. If you shine a light at the edge and just look at it by eye you can also usually spot it if you rotate it a little and check both sides. You can also tell by feel if you are experienced, or try a little shaving and see if one side is much better than the other.

Cougar, yes, this like "custom" is one of the knife-words that has been used less than ideally from the natural english defination. A clip vs drop point is a profile issue whereas a hollow vs flat primary grind technically isn't.

-Cliff
 
The tests that I have found most helpful in detecting a burr are looking at the edge with a bright LED light, using the "samurai hair" test (put the knife on the back of my head and run it down my hair) and sometimes shaving. For the last two tests, if the knife has a burr, it will run down my hair (doesn't stick) and it will shave much easier on the assumed burr side.
 
Slowly, if you chop the knife into the paper fast you can do it with a really dull knife. Essentially you are not giving the paper time to buckle under the impact.

-Cliff
 
CMSpeedy said:
It is admittedly way uglier than yours.
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Is that a challenge? Has the gauntlet been thrown down?

A little prettying up may be beneficial to the knife's performance in terms of reducing footholds for corrosion (learned S30V will rust easily with a scratchy enough finish) and places where strain may be concentrated and amplified.

Cougar,

Thanks for providing the useage of reprofiling I hadn't considered.

db,

If it weren't for you, I wouldn't have gotten that Carter vid from TedGamble and learned that even I could freehand. What you're seeing in those two Delicas is also the influence of folks like Cliff Stamp, Joe Talmadge, and Alvin Johnston. Though Alvin would've had me tear the blades out and make new ones out of 1095 or 8670-mod and hollow grind much thinner bevels... He's very good like that.
 
Cliff, I am a bit confused as to push cutting newspaper. Is it the flimsiness of the paper that makes it harder to cut when you try to cut farther away from where you are pinching the newspaper? The way I'm doing it, it doesn't really seem possible to do it ~3 inches, no matter how sharp the knife is. I can get around .5 to 1 inch with my Sebenza. Please tell me if I'm doing it correctly.

Say
-----------------
is the top of the newspaper.


-[]--------------

I pinch it there, and have the rest of the paper hanging loosely?

..then try to cut here:

-[]-----|--------

Doing it this way seems as if no knife will cut the paper due to the paper being flimsy. Is this the actual test for sharpness - will a truly sharp knife cut the paper, even if it is flimsy?
 
I have come to prefer a highly polished edge on most of my knives. I use a paper wheel and then hand strop. When I get the edge really sharp the slicing and push cutting performances seem to merge and the durability of the edge increases.
I am visualising that this is because finer serrations usually mean faster cutting but also faster wear as the 'points' are sharper. Polishing the final bevel would leave it smooth in the longitudinal direction and hence stronger--no 'points' to wear.
Hmmm-sounds OK--any comments?
Greg
 
Django606 said:
Is this the actual test for sharpness - will a truly sharp knife cut the paper, even if it is flimsy?
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Yes, essentially you are using the tension in the paper to measure the sharpness. Moving significantly out past the point at which it is held is very difficult. For quite some time I had been satisfied if edges would push cut paper at all.

-Cliff
 
Would it be best (or easiest) to use a strop or other very fine abrasive to do the deburring from an edge that would push cut paper to an edge that would push cut newsprint at around 3 inches?
 
A high polish does increase the ability, but you can get a crisp edge even with a coarse finish. I have seen edges exceed an inch which were sharpened on a 90 grit hardware store hone.

-Cliff
 
I'm assuming edge angle has a lot to do with it as well? Do you think if I reprofiled my Sebenza from 20 to 15 degrees I would notice a big difference?

I'm not even going to attempt to reprofile it yet with just a Sharpmaker. I either need to get the diamond stones or an EdgePro. It took me a long time just to go from 22 or 21 down to 20.
 
I wouldn't suggest buying an EdgePro for reprofiling speed. Buy it for getting your bevels consistantly gorgeous and sharp. If sharp is all that matters, get a coarse benchstone for a few bucks and reprofile your knife in minutes (maybe as much as 20 minutes if you're going from 20 to 15 degrees and taking your time to not mar the blade's finish on your first time not using a practice blade).
 
Yes, it gets easier to do any cutting test of sharpness as the angle is made more acute and thinner.

-Cliff
 
The EdgePro comes with extra coarse stones though, doesn't it? I am also looking for perfect bevels. I guess I'm considering ease of use as decreasing reprofiling time.

What about with/without a microbevel? Say I just reprofile it to 30 degrees, would that be better or worse than 30 degrees with a 40 degree microbevel? What exactly would be the difference in cutting ability, edge retention, etc, with and without a microbevel?
 
Django606 said:
The EdgePro comes with extra coarse stones though, doesn't it? I am also looking for perfect bevels. I guess I'm considering ease of use as decreasing reprofiling time.
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The coarse hones are sold separately (and worth every penny). You may ask for perfection, but since wordly materials and human hands are being used, you'll get something else. Parts of the edge that don't touch the middle of the blade table won't have an angle that's exactly as listed. What's okay about that is the angle will still be consistant and you can always do better when 'perfection' is no longer a destination.

Why don't you drop me an email and we'll talk about this reprofiling a Sebenza on an EdgePro to about 15 degrees per side idea. My addy is tbrogan1 at netzero dot com
 
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