Am I On Track?
- This topic has 26 replies, 6 voices, and was last updated 08/08/2019 at 3:26 am by
.
-
Thank you so much for that detailed feedback. I’m aware that it’s going to take me awhile to figure out all the tricks of the sharpening trade but I’ve got nothing but time. Regarding the photo I sent in, that was one of my questions. That was my final bevel, a 15 degree using the 1600-grit ceramic stone but like you said, the apex is showing signs of the original scrubbing. I’m wondering what my next move should be to smooth that out. Do I need to just continue stroking with the same stone or contemplate another technique?
Just adjust your angles by about +0.2 degrees, or about two-thirds of a turn out on the micro-adjust screw. All of the stones I use seem to match angles beautifully, except for one of my 1000-grit stones. It measures almost 0.2 deg. higher than the previous grit . If I recall correctly, that probably is caused by a 0.020″ difference in the mounting height of that particular platen. One annoying complication is that it throws off the measurement when I want to reset the angle for the 1500 grit on the opposite side of the same handle. Of course, this is because I place the angle cube on the 1000-grit surface. Maybe if I put it on the rod itself…
Just applied this to a Sog of my son’s and wow, it worked great so thanks for the tip!
1 user thanked author for this post.
Here’s something I still don’t understand. Like many of you, I start out by grinding up and down until the blade apexes on both sides with burrs. Next I begin stroking with the same stone until either the Sharpie is gone or until all the vertical scratches are gone from the stroking. My question is why does it seem like the bevel of the blade has changed in between the two techniques? If I grind at 17 degrees and then stroke at 17 for example, why does it seem like 16.9 when stroking? Most of the time, I have remove more material towards the bottom of the bevel to reach the knife edge. Now that makes so sense. Am I doing something wrong? Here’s an example, this is after about 50 strokes and I’ve got a ways to go.
Richard, I found I did the same thing when I was just getting started. My technique has improved so I don’t see those drastic scratch differences any longer. I found, for me it was a pressure related and hand and finger position on the paddles related result. When I found a single hand and finger position that I used comfortably for all my different strokes I didn’t see those drastic differences in bevel shape any longer. It took a lot of time and practice.
Try to use each stroke in your progression, even with the same grit, long enough that your new scratches over come the previous scratches laid down with your first direction strokes. The scrubbing lays down one scratch. Do the next stroke long enough and thorough enough to over come the scrubbing scratches with the new scratches. Sometimes by moving your finger position on the stones this directs your pressure differently enough to help over lay the first scratches, with the new scratch pattern and direction. I spent a lot of time and effort looking at the scratch directions and positions, associated with each of my different sharpening strokes, using the USB microscope. This helped me to learn what finger position and pressure worked best for me to refine my technique. Now my results are more predictable and uniform.
Marc
(MarcH's Rack-Its)3 users thanked author for this post.
Thanks Marc, I attached a photo to my last post. Maybe I could try reducing the amount of downforce after I achieve good results and reduce the deep scratches so when I do transition over, my work will be reduced in stroking.
1 user thanked author for this post.
I suggest you try different things and look at the visual results with the USB scope. Be systematic about it so you can keep track of cause and effect. Do it one way on both knife sides. Make subtle pressure and finger position changes and look at the effect or results in the scratch pattern. Do it slowly and systematically enough that you can correlate, cause and effect.
For me I found turning or rotating the USB scope around 180º so the edge is oriented upward in the screen view, like it’s clamped “edge up” position it made it easier for me to see and relate to where I was on the knife’s length with my scratches.
Also, I double check and make micro-angle adjustments with the cube each and every grit change.
When you get your technique down, each successive grit will lay scratches down, right on top of the previous scratches, across the entire height of the bevel. It’s all about the consistency in my technique.
Marc
(MarcH's Rack-Its)3 users thanked author for this post.
Interesting that you check your angle cube each time.
1 user thanked author for this post.
Richard,
I also check the angle at each grit change. I have also checked the angle while using the same grit stone.
Especially with scrubbing, the knife may have shifted ever so slightly. Since I do mostly pocket knives with a variety of shapes and sizes, it might happen to me more than others who do more kitchen size blades.
When I clamp the blade I draw a sharpie line from the middle of the vise up to the tip on both sides. I also use a fine tip sharpie to draw an outline of the vise clamp on the blade. This way I always rest the paddle at the same sharpie spot when doing angle measurements for all the grits. And I can easily check if the blade has shifted in the vise.
Hope this helps.
Ed K.
My theory is that helps overcomes any inconsistencies seen in mounting or plate thickness or plastic paddle molding seen from stone to stone. It’s usually only a very slight micro-angle adjustment. Only on one stone, my 800/1000 is it the same from side to side. Every other pair requires fine tuning.
Marc
(MarcH's Rack-Its)BTW, I only zero the angle cube at the very beginning of the sharpening session. Then not again, till another, or different knife.
Marc
(MarcH's Rack-Its)1 user thanked author for this post.
BTW, I only zero the angle cube at the very beginning of the sharpening session. Then not again, till another, or different knife.
I see what you mean about developing your own techniques and methods. I’m getting there though.
I do the same, and I’ve found I don’t need to check again, once I’ve set the angle, unless something seems wrong. I have learned that my 1000/1500 stones need to be adjusted down by 0.2 degrees on one side. Can’t imagine what might be causing it. I mounted all my stones in one sitting, using the same batch of tape. That’s about 6/10ths of a turn on the microadjustment for that side. The only trick is to remember to set it back up by the same amount. The angle cube is the gold standard for checking it.
1 user thanked author for this post.
- You must be logged in to reply to this topic.