*** Getting The Sharpest Edge Ever ***
- This topic has 9 replies, 5 voices, and was last updated 04/02/2017 at 5:54 am by
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I’ve been using a WEPS system for going on six years now, but I learned only this past year how to get a really sharp edge. I’ve been quite happy with polished edges and micro-bevels, but now I know (or think I know) that eliminating evidence of a prior grit isn’t enough if you want true razor sharpness.
If you look at your edge with a medium power USB ‘scope (150 – 400X), you’ll see that although the scratches are gone, there’s still evidence of prior grits at the edge. Edge-trailing will exacerbate the damage at the edge, but edge-leading will also leave some damage, but not as bad. If you are going for really sharp, you continue to stone until ALL evidence is removed – both scratches and raggedness at the edge. This is a bit problematic because as you are removing the raggedness from a prior grit, you are leaving some with your current grit. How to tell the difference? Darned if I know. What I have been doing is watching for prior-grit scratches and when they’re gone, I continue with two or three times the number of strokes it took to remove the scratches.
I avoid getting anywhere near the apex with grits below 400. This means I have to do a lot of 400-grit work, but the lower grits produce deep notches at the edge and these take a really long time to remove.
Knife: Any
Edge Angle: My ZDP-189’s tend to get chips at angles below 18 dps. I’ve been sharpening them to 19 dps, or 17 dps with a 20 dps micro-bevel. In general, lower inclusive angles make for sharper blades, period. The question is what’s practical for the knife and the application?
Edge Leading or Trailing: Edge leading with diamond stones, trailing with film. I’d prefer leading with film, but it just slices the film. If I can see that I’m not getting near the apex, I’ll use scrubbing strokes to move things along.
Finished with: I usually follow a sequence of 400/600/800/1000, then 6 and 3 micron film. If I’m going for a Hanging Hair Test, I’d add 9 micron film between the 1000-grit and the 6 micron film and after the 3 micron film continue with 1.5, 1.0, 0.5, and 0.1 micron films.
Degree of sharpness: Probably HHT2. I hit HHT4 once with my Delica.
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Awesome advice TC, and thanks for posting! I’m curious as to why you only use the 9 micron after the 1K when going for a higher sharpness level? Does the 6/3 combo not completely polish out the scratches from the 1K? I understand going all the way down to 0.1, but was just wondering why you only use the 9 micron when doing a full progression.
I do this because while the 6 micron film does really well in erasing the scratches from the 1000-grit stones, it’s a pretty wide spread from the 1000’s and would take longer to repair the 1000-grit edge damage than the 9 micron. Please understand that I haven’t done an extensive series of experiments to prove this; it just makes sense to me.
Tom, if you make edge leading strokes, do you go straight down, or do you also make some horizontal movement?
I have a sheet hanging on the wall next to my workstation which indicates which direction to take for each grit. I alternate directions for each grit – down and towards me for one and down and away from me for the next. Of course, when I get up into the films, it’s up and toward me/up and away from me for edge trailing. As I’ve gotten older I’ve noticed that my short-term memory ain’t the greatest and it helps to be consistent, so I try to always use the same pattern so I don’t lose track of where I am. I’ll use vertical and/or scrubbing strokes where I’m trying to remove more steel more quickly in a specific area
I think Josh at RazorEdgeKnives is the real authority on this matter, so I’m really interested in what Josh and Clay think of my approach. Any comments Clay / Josh??
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This is all great information. I have learned a lot of good tips on this forum, which, is why I keep coming back. The problem with trying to “Standardize” a process is we are all working with way too many variables. Different metal compositions, different finishes on those metals, Rockwell Hardness, heck some would even say the position of the moon and stars and weather make a difference at the edge. Even Notverysharp was typing about placing a blade under a pyramid is said to have a effect ( Probably joking but heck some people really believe it and why should I care). And then , you get into the human factors of strength, perception, eyesight and tactile pressure applied or not applied.
I swear a blade that yesterday I perceived wouldn’t cut today when tested is amazing. Did something happen when I wasn’t watching? Doubt it, but one never really knows for sure (Its “woh0o” SHIT, I know). But I think everyone has had a experience like it.
My formula for success is tailored for each blade. As soon as I think I have it, I learn something else and rarely can I actually duplicate the exact result on a different blade. I can get close but not exact. I just keep pushing the blade to be the best it can be (I sound like Murry Carter LOL). Even the tests we are all doing are subjective. Was the hair you are testing damaged, or clean, does the soap you use alter the result. Was the paper bonded properly or is it single or double ply. As much as we try, (at the end of the day) “Wicked Sharp” is different for everyone.
The techniques of what not to do are just as important as the techniques needed for success. For me it is about keen observation, consistency, and determination to improve not any specific formula for achieving it. We all have the right tools and are all working to get better, for now at least for me, I think that is enough. It is fun trying new things, working together on forums like this to solve common problems and helping others to achieve great results. Sorry- Off my soap box now.
Eddie Kinlen
M1rror Edge Sharpening Service, LLC
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