Yet another bump. My dad recently gave me his Cutco hunting knife to sharpen for him, which as the normal double D serration pattern. I've previously sharpened this knife with the SharpMaker, but it was tricky and took a long time.
Today I started with the SharpMaker, but I was determined to use the "flat side first" technique. I went nearly flat on the brown SM rod (flat side of blade to flat side of rod). I should start by saying just how dull this knife was: Every single serration reflected light back at me when viewing it straight down. One or two of the serrations was chipped as well. This was one DULL blade.
After 10 or 15 minutes on the SM brown, I had reduced the reflection width on all of the points, but had only gotten maybe one or two of them to have no reflection. After de-burring, the knife would tear and kinda cut phonebook paper, but it was not sharp. The teeth slid easily over my thumbnail without biting in. I set the blade aside and did another knife.
When I came back, I thought, "Why not use the DMT EF on the flat side for a short while? Just a few strokes can't hurt right?" I set to it, after putting marker on the back side. In a short while I checked and I had actually removed the reflection from some of the serrations. I kept going and in a few more minutes had all the reflections removed, except in the curved upper part of the blade. Checking sharpness with my fingers, there was an amazing difference. Thumbnail test worked too, as the points bit into my thumbnail when dragged over it. The curved part continued to slide over the nail validating that the reflections really did mean it wasn't sharp.
It took more effort to get the reflections to go away at the front, and in fact, I decided to stop with one or two of the points still reflecting light, as I didn't want to remove too much metal all at once. As it is, I can see where I've taken metal off, but it's mainly a difference in finish, as opposed to some big bevel I've put on it.
I deburred using the white SM rod corners and then polished the back with the flat of a white SM rod. I went back and forth a few times and drew the blade through cork to deburr as completely as possible. It now slices phonebook paper relatively cleanly, though it isn't quiet like a plain blade. It's also sharp enough to catch some hairs on my arm and cut them. Again, no where close to the shaving from a plain blade, but it's a measure for me that this is a quite sharp serrated blade.
This is my first full validation that sharpening serrated blades from the flat side totally works, and I'm now unafraid to use something more coarse like the DMT EF to do so. I'm still hesitant to go as far as the DMT C, but maybe I'll try that on some really beat up serrated blade I don't care about.
I'm stoked with my progress on this.
Brian.
