micro bevel to eliminate tear-out -Spyderco Paramilitary CPM-S110V
- This topic has 38 replies, 7 voices, and was last updated 12/06/2022 at 11:08 am by
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Hello all and thanks for bearing with me through this probable pic-intensive thread.
I’m both sharing a newbie to the WE experience, AND looking for guidance on preventing tear-out of the edge.
I’ve been sharpening knives and woodworking tools for a LONG time on whetstones and a Tormek, so I’m not new to the game, just new to this tool.
I bit the bullet and bought a WE Gen 3 pro. It arrived last week and I broke in all diamonds, mostly, on some beater knives, probably did about a dozen sharpening sessions on cheap, soft steel, but had to reprofile many… just because – and to break in the diamonds. All strokes have been low to very low pressure. Mostly.. I admit I hogged out at medium + pressure with the 100’s because I had a LOT of cheap/soft steel to remove from a “survival” knife. But I digress informing you of the stone break-in process. They’re probably not fully broken in, but very noticeably smother then initially.
So I was itching to move to a “good” knife but am still hesitant to use the set-up on my higher-end kitchen knives so decided to sharpen the Spyderco Paramilitary with CPM-S110V steel.
15 DPS seems the Spyderco standard, and indeed my sample was rather close but not exact. Good start. This knife is fully tapered from spine to edge so clamping it was … a bit of trial and error, but I got it really close to dead centered.
Used the low angle adapter to reach the 15 degrees per side and micro adjusted each arm to 15deg. I Used an angle cube to dial in 15.00 deg. +- .05. I used a sharpie to validate that indeed the 15 dps was “spot on and it was really close so I ran with it. Although I started with 1000, it was WAY to slow to get me going so I decided to back off grit by grit but wound up down at 100 grit diamonds to “re-profile”. Then 200, 400, 600, 800, 1000, 1500, 2200, 3000. Each grit I used a combo of leading and trailing edge strokes, but mostly tried to do edge-leading as I was noticing tear-out on the USB scope.
After the Diamonds I proceeded to to 1200 / 1600 grit ceramics, then the 6, 3, 1 an finally .5 micron Diamond lapping films. Finally I backed off the angle 2 deg. and stropped diamond paste on leather 4,2,1, and .5 micron. The whole arsenal was used!
I started noticing tear-out on the edge from the very beginning, and neither edge-leading nor edge trailing strokes made any improvements.
So – After pondering, I decide to put a 2 deg micro-bevel on the edge using ONLY the ceramics. Eventually, I got to a quite nice, although still not-perfect edge.
One question is: Are Diamonds known to tear-out CPM-S100V? Was my technique wrong? Can anyone offer guidance to eliminate tear-out using only diamonds?
Here are SOME photos of the progress.
Sorry – but I’m new to the forum from my laptop and I think photo insertion is something I need to get better at
Final “happy” blade
Early hot showing some tear-out at 100 grit.
mid shot (1000 grit) showing tear-out still there
3000 grit – Yup – not a clean edge STILL – Note – VERY light passes on the stone…
I’ll add more files in a second post once I see how these few format.
So the formatting looked good. Photos came in where and how I expected, so here are a number of sequential photos.
The set-up ( after the final passes of micro beveling and a “happy knife” on a messy kitchen counter.
100 grit – starting point
200 grit – not any better tear
Skipping 400 and 600 progression photos – 800 grit is showing nicer scratch patterns, but there is still edge tear-out!!!!
About at 400, I think, I “zoomed” in the USB scope to it’s “second” magnification power ..
2000 – yup, the tear-out is still there!
To be continued – out of space apparentlyout
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3000 – shiny, but the edge still “micro-grabs” when slicing paper – photos
1200 then 1600 ceramics…
Lapped with diamond film (1.5 micron pic shown) – still have tear-out!
Stropping (at 2 deg. less ) still didn’t help … duhhhh
To be continued ( size limitations ???)
Time to put on a micro-bevel WITH OUT diamonds. Ceramics – films- strop… hummm, will this work???
1600 ceramic – 2 deg mico-bevel .. SUCCESS! But why are the diamonds tearing out the edge?
So I progressed to DLF and stropping (2 deg out from the micro-bevel)
I’m generally pleased with the edge, but want to understand / learn about the edge chipping…
bevel 17 deg – 1600 ceramic-1.5 micron lapping-2.jpg”]
And a final strop.
Welcome to the forum, Henry. Nice photos!
I don’t like Spyderco knives so I don’t know much about them. And I haven’t sharpened anything with that steel yet. But I hear that most manufacturers use dry belts to profile/sharpen their knives with. That can build up heat and ruin the heat treat to the steel at the edge apex.
I would sharpen/reprofile the blades until I got down to some good steel. You can also test the steel to see what the hardness of the steel is. I use Tsubosan files to test the steel hardness of my blades. They aren’t exact but they give you a good idea where the RCH of the steel is.
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Henry, I believe you have a couple issues going on there…
First, like you said, the diamond stones may not be fully broken-in yet. I think you’ll continue to see further improvement in the resulting scratch patterns with continued use.
Then it appears your technique may need more practice and ultimate improvement. Although it’s a little difficult to follow the submitted photos, as the magnification is not the same ‘high power” for all of these, it appears that your stonework may not be apexing the bevel with every grit you used. Some photos it appears your right where you need to be and others it appears you’re not reaching the apex. Some photos I see a clear burr in place while others it’s not there. (I know there are a lot of factors involved like when and where the photo was taken that may be misleading me).
As “tcmeyer” sometimes points out, there is a slight difference in the diamond stone thicknesses as the grits become finer and finer. Because of this, I’ve learned to double check my set angles and make micro-angle adjustments with each and every grit I use. Working with the precise angles the W.E. allows us to utilize, the angle cubes allow us to adjust for and the visual results of our adjustments the USB scopes allow us to see, it requires a higher degree of attention to detail, on our part, to make use of this precision.
It’s also important to employ the same finger hold position with each and every grit. Depending on how and where you place your fingertips on the stone paddle can affect where the scratch pattern is applied to the knife edge. So, consistency is key.
Don’t fall in the trap looking for something wrong, like steel hardness, to blame or explain unacceptable sharpening results on. Steel hardness is a contributor to our sharpening difficulties. That’s why I employ different sharpening mediums that I have found to be better suited for the steels I’m sharpening. I believe Spyderco does apply a heat-treatment to their steels resulting in a slightly harder HRc rating then others may utilize. This harder steel seems to have a greater tendency to be chip prone when sharpening it. Also, realize you’re inspecting your edges under magnification, so the chips and sharpening defects are not really as bad as they appear they are. What some may call edge “tear out” is simply the normal grit’s scratch pattern following off the apex. I’m not saying the diamond stones can and will give you the results you seek with the CPM-S110V. Just not to jump to conclusions yet. Keep working on your technique and using those stones more.
I, like tcmeyer, also utilize an alternate side, left-right-left-right, edge leading sharpening stroke. For me it’s the final stroke direction with each and every grit. This removes any resulting burrs and wire edges that were applied with edge trailing strokes.
I will finish by saying, look into the technique for applying micro-bevels and the purpose(s) for using them. Of course, it’s your knife, so you’re welcome to it anyway you like.
Marc
(MarcH's Rack-Its)1 user thanked author for this post.
As I promised, here are a few photos of the edge POST blending the microbevel on a series of strops (down to .5 micron). I did a series of about 4 progressive angle increases stopping 2 deg. above the final microbevel angle.
In this one you can see the “rough” scratches that indicate to me anyway a LACK of fully polishing with each and every grit. This clearly is using the USB scope on the “low” power…
Here you can see some of what I am calling tear-out. This is WAY better than initially, cuts like a hot knife through butter, but I am looking for BETTER as my technique (and perhaps the stones break in) improves.
That’s all for now.
I look forward to further constructive criticism and guidance as I continue down this journey.
I think I’ll try and do a different folder next, although I’m tempted to try and redo this one from the ground up.. uggg, the edge really is wicked sharp now. I can’t wait ’till I know what I’m doing and able to get to the next level!
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