Toothy edge - Scotch brite belt(1)

[blgentry]

I just sharpened my Spyderco PM2.  Link for reference:  https://www.bladehq.com/cat--Spyderco-Pa...view--3425

It was dull-ish.  The first inch or so was noticeably dull, while the rest was still fine, but not as sharp as I would have liked.

I used what I've been using on everything:  A Trizact A100 (180 grit).  Got a burr on both sides.  This required a good bit of work at the tip.  I'm using an angle guide and apparently my natural way of moving through the tip isn't exactly "true" to a constant angle.  So I had to adjust and make sure I was on the guide *and* keep moving the handle of the blade so that the edge makes contact with the belt *alllllll* the way to the very tip.  I reduced the burr a bit with the A100, then moved to the Very Fine Scotchbrite belt.

I was able to duburr about 80% on the VF.  Next I used rough side bare leather.  After 6 or 8 passes, the burr was mostly gone but was hanging on near the tip.  So I did what I've been doing:  Back to the VFSB.  This is weird for me to move back and forth between belts.  But there seems to be something about the bending or abrading action of these that compliment each other.  After a few passes on the VFSB, the burr was essentially gone.  I did a thumbnail test to see if I could feel any LOW and I could.  Mostly near the choil of the blade and only on one side.  After a few touches to the SB and a couple of very light passes, no more LOW, no more visible burr.  So... back to the leather for 2 or 3 passes per side, lightly, at the sharpening angle.

Flies through phonebook paper.  Shaves pretty well.  What about the BESS?

Base:  120 .  Middle: 145. Tip:  165
Average:  143

That's my best single score so far.  Probably also my best average?  Not that I'm counting. 

I would like more consistency, but I'll take this for sure.  

I've been concerned about sharpening "nice knives" on the Kally.  The thought being that I can do cosmetic damage to the bevel very quickly, especially if my angle control is poor.  This blade seems to prove that I can do a very consistent job with the bevel in terms of cosmetics.  It looks "better than factory".  I think most people, even some knife nuts, would be satisfied with this job cosmetically.

I'm definitely satisfied with it overall.

Brian.

[grepper]

Great post Brian. Thanks for sharing.

It’s interesting but probably not surprising since you are using the same equipment as I do and basically the same belts that your process mirrors my own almost exactly.

For me learning to deburr with Scotch-Brite (SB) does indeed require some practice.  I’ve become better at it with time, but still every knife is different.  A lot of the time after the SB + leather I’ll see some bits of remaining burr and have to work on those areas.  But just like you have described eventually the entire burr gets removed and the wonderful toothy edge is preserved.

With the Kallyrest, keeping the blade flat against the rest and keeping the blade in contact with the belt when going around the curve at the tip requires some practice too, but it get much easier with experience.  It helps to sharpen the tip at the edge of the belt nearest the tip by tilting the blade up to keep as much of the blade against the rest as possible.  In other words, when the tip contacts the belt try to keep the tip at the edge of the belt rather than in the middle of the belt.  The bevel angle remains the same, just more of the blade stays in contact with the rest.  

As you have seen, getting an even bevel it not difficult and I’m sure that any concerns about cosmetics will soon pass.  Sure, you could just jam the blade into the belt and screw things up but with any amount of care it’s a non-issue.  With an over abundance of caution I still take a couple of passes with extremely light pressure just to understand what I’m dealing with.  That shows what the particular knife requires as belt pressure goes.

For me, the curve at the tip is always the most problematic and shows the greatest variance in BESS numbers to the rest of the blade.  As long as an even burr was formed along the curve it’s usually because there is still remaining burr along the curve.   In your case with 165 it’s not significant, but I suspect burr is why the numbers are a bit higher.

Like I said, with a 165 reading there is no reason mess around with it, but FWIW here’s a little trick I use that may or may not help depending on if burr is the issue.  Hold the blade at almost 90° to the rough side of the leather belt and then just “tickle” the edge against the belt.  The reasoning here is that any tiny bits of remaining burr will be bent at a sharp angle and cause them to fracture off.  Then flip the blade and do the same.  Then a pass or two at sharpening angle at moderate-light pressure around the curve.  Many times I’ve seen the sharpness reading drop by 10-20 points.  

The cool thing to me is that you have only had this setup/process for a short time and you’ve pretty much got it figured out.  Practice make perfect but still every blade is different and there are so many variables such as sharpening angle, burr size, LOW, etc.  Then it’s just a matter of applying experience to the blade at hand.

Thanks again for the post and the BESS numbers that tell the story.  I always find sharpening stories both informative and enjoyable to read.