New to sharpening – question about technique
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Cameron, the angle markings/indexes on the square bare are just an approximation. You should set your desired 17º (dps) angle using the angle cube. Is that what you did when you determined the actual angles were more like 15.4º and 15.8º ? After you realized the actual measured angles (i.e., using a zeroed out digital angle cube) were less then desired, did you loosen the locking screws and move your mini “L” brackets wider out from their current setting by a couple divot holes, then rechecked the angles with the angle cube. At this point you should make your fine tuning adjustments with the micro-angle adjustment screws, in or out as needed to reach your 17.0º setting. (Within your devices resolution is fine if that’s the best you can achieve). Then when both sides are measured at 17.0º with the diamond stone leaning against the knife edge at the center of the vice, you should make sure all your adjusting screws are snugged tight to prevent any movement while sharpening.
I always start with a scrubbing motion to one side. When I feel the burr on the opposite side along the entire length of the knife edge, heel to tip, I’ll switch the scrubbing to that opposite side and repeat the entire process. Remember it’s usually easier and quicker to raise the burr on the second side than the first side burr. Drawing a burr is a physical indication that you’re grinding steel off and up to the edge of the knife edge, (i.e., the apex). I continue stroking till both sides are equal in the bevel height. At this point I do left-right-left-right alternating strokes to insure I have brought the edges up to the center and apex. Then I feel all along the entire length of the knife edge heel to tip to verify even sharpness. I continue to work the as necessary till it feels evenly sharp along the length of the edge. I use a lighted magnified visual aide to verify I have reached my apex, each side bevel is equal in height, and my scratch pattern appears consistent along the entire blade length. Then I’m ready to step up a grit. Each different knife and each different steel depending on its starting condition can take more or less time then the next knife. I do not count strokes. I work by feel and visual inspection of my progress.
I do not draw a burr again with subsequent grits. I believe it is unnecessary and waste steel. I check by finger feel for sharpness. The knife edge should look and feel smoother and sharper and the scratch pattern should get finer and closer together as you progress through the grits. I do verify my set angle with the digital angle cube at each grit change and micro-adjust accordingly. Other Wicked Edge users may not do this. It’s up to you your preference.
Each grit I start with a light one sided scrubbing stroke across the entire blade length heel to tip then switch sides. I again follow up with alternating left-right-left-right strokes doing it, again, systematically the same, to blend the length of the edge and verify it’s apexed along the entire edge. When it sounds right, feels right and looks right I’ll move up to the next grit. Again I don’t count strokes. I attempt to keep my work even side to side and visually verify my progress. Each subsequent grit may take less effort than the prior grit.
I do check the edge for progress of sharpness at each grit by pulling a small square piece of news paper down onto the sharpened edge while holding the paper at the bottom corners. As I work up the grits I can feel the paper cut easier, smoother and with less resistance. If not I look to see what needs to be done to make improvements.
When I finish with the final grit level I want to utilize I reduce my set angle by 2º each side. In your case, to 15º. After cleaning the knife edge and blade sides clean of debris I begin a strop progression. This is always edge trailing, up and off the edge, and alternating, left-right-left-right strokes. Depending on what I’m sharpening and how polished an edge I want I’ll either use a two grit strop progression or four grits for a more polished bevel. It’s is very discernible, for me, the different in edge sharpness feel between unstropped and stropped knives. A properly sharpened knife, (i.e. with the edge drawn to an apex) when stropped should be easily able to push cut news paper if it was sharpened with enough care and proper technique.
I have been able to easily push cut newspaper with a knife made of cheap soft steel sharpened at 20º dps that was stropped in two grits, 4µ/2µ. I believe time and technique makes the different. Stropping is always the very last and final step.
Marc
(MarcH's Rack-Its)How many knives have you sharpened at this point? My experience was that the first several knives did not turn out nearly as sharp as I had expected. Like you had done, I also used the diamond stones without the strops. My first edges were similar to yours; slicing paper, but not smoothly and not push cutting. I suspect that the strops will help a lot with performance.
In contrast, I sharpened a very cheap Faberware kitchen knife on Saturday. I sharpened it at 20 degrees per side and only up to 600 grit. I then stropped it with the 4 micron / 2 micron strops. It push cuts thin news print and is hair popping sharp. It won’t hold that edge for long because the steel is very soft, but it only took about 10 minutes of work to get it there.
Follow Marc’s advice and keep sharpening cheap knives. It won’t take long for things to improve noticeably.
I want to make a point here regarding the initial objective of reaching a burr on one side. We’ve preached here about producing a full-length bur on one side before proceeding to the other side. But if you have a REALLY dull knife and work one side only, your apex will be well off-center when you finally get a full-length burr. I suggest that you work both sides alternately – maybe 10-20 strokes on one side, then the same number on the other side until you produce at least the start of a burr. Then you can stay with that side until the burr is full length.
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I can suggest from experience that the stropping emulsions will stay on the leather better and last longer if you apply it the day before you intend to use the strops and allow the emulsions to thoroughly dry overnight. When I use the dried strops I get very little scrape or flake off.
The 2º reduction from you sharpening angle is a general recommendation. I have found that 1-1/2º gives me the results I am looking for. After you reapply the strop emulsion and allow it to dry, try again with an angle 1-1/2º under your sharpening angle or even 1º less. You have to adapt the recommendations or suggestions to give you the best results with your sharpening technique. These suggestions need be individualized.
It’s even possible the 2º is too little of an angle reduction for that very soft steel. You may have rounded off the apex with the 2º attempt. Without using something like a USB Microscope it’d be hard to make that determination.
Either way, I’d reclamp the knife to your sharpening angle, touchup the edge with the 1000 grit to bring back the sharp edge you were satisfied with then try your stropping process again. You can check for sharpness while the knife is still clamped by pulling a small square of news/magazine paper (like 3″ X 3″) held by your finger tips on either side of the clamped knife. Pulling the paper down against the sharpened edge is similar to the action of push cutting. It will give you a good indication if your getting sharper in your process or causing edge deterioration.
PS: I too have had problems with diamond emulsion spray applicators. To my disdain, had to apply the emulsion using the tube inside under the spray cap as an applicator stick. I rinsed the sprayer to no avail.
Marc
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But if you have a REALLY dull knife and work one side only, your apex will be well off-center when you finally get a full-length burr. I suggest that you work both sides alternately – maybe 10-20 strokes on one side, then the same number on the other side until you produce at least the start of a burr. Then you can stay with that side until the burr is full length.
This is an excellent point, thanks Tom! I like to coach people to color in the bevels again once they’ve determined the sharpening angle they want and then alternate sides with every stroke until the marker is almost all gone and nearly invisible to the naked eye. At that point, it’s good to then focus on one side until you draw a burr along the whole length of the blade and then switch to the other side and and work until you draw a burr.
-Clay
When I first started using the strops I did the same thing you did; light pressure and 2 degrees per side angle reduction. Also like you, I concluded that the edge didn’t seem any better than it was after the stones. The combination of light pressure and 2 degrees more acute angle means you’re likely hitting the shoulders and not the actual apex. Try using more pressure and 1.5 degrees per side angle reduction and see what happens. Stropping is one of those things that you have to get a feel for. It will do amazing things for your edge when you get the technique dialed in.
Those strops appear well covered. Is that the WE’s 4µ and 2µ diamond emulsion spray? My sprays are more dark muddy brown/muddy gray in color when I apply it to my leather strops. My diamond emulsion sprays are an older product WE sold, a while back, when they got those products from a different supplier. My strops are older too. They’ve been cleaned and reapplied a few times. That may contribute to their darker appearance.
I’ll be curious too if you like the way it stays on the leather. I recently cleaned my strops then reapplied the emulsion and have since stropped seven knives with good results. The strops still appear well embedded though the leather is more shinny now.
Marc
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Cameron if your new to sharpening and your diamond stones are new, It takes time for your diamond stones to break in, and time for you to learn how to use them properly and develop and practice good sharpening technique. There is a learning curve period of time it takes to put it all together. Then you’ll start to see improved results. The stone break in is about 8 or 10 knives and by that length of time users usually figure it out.
Looking back I see you’re at it for about 5 months now, I’d expect you’d have a handle on it by now and seeing results to your liking. If your not seeing sharpening results you feel are worthy yet, then please share with us in detail your progression and technique. Maybe we can help make suggestions to help you with your results. You really didn’t say whether you felt the knife wasn’t sharp enough or that it wasn’t shiny enough! The shine and sharp develop all along the entire process as you progress from stone to stone and then continue with the different mediums. It’s true that strops are considered a polishing step more then a sharpening step. But if your sharpening steps with the diamond stones weren’t done well enough and correctly the polishing strops may not be able to give you a shiny sharp knife.
PS: I did look up your stropping diamond emulsion and find that Wicked Edge doesn’t call it a spray although it has a spray or squirt applicator top. I use a similar diamond emulsion product.
Marc
(MarcH's Rack-Its)Cameron if your new to sharpening and your diamond stones are new, It takes time for your diamond stones to break in, and time for you to learn how to use them properly and develop and practice good sharpening technique. There is a learning curve period of time it takes to put it all together. Then you’ll start to see improved results. The stone break in is about 8 or 10 knives and by that length of time users usually figure it out. Looking back I see you’re at it for about 5 months now, I’d expect you’d have a handle on it by now and seeing results to your liking. If your not seeing sharpening results you feel are worthy yet, then please share with us in detail your progression and technique. Maybe we can help make suggestions to help you with your results. You really didn’t say whether you felt the knife wasn’t sharp enough or that it wasn’t shiny enough! The shine and sharp develop all along the entire process as you progress from stone to stone and then continue with the different mediums. It’s true that strops are considered a polishing step more then a sharpening step. But if your sharpening steps with the diamond stones weren’t done well enough and correctly the polishing strops may not be able to give you a shiny sharp knife. PS: I did look up your stropping diamond emulsion and find that Wicked Edge doesn’t call it a spray although it has a spray or squirt applicator top. I use a similar diamond emulsion product.
Marc, I really appreciate the reply. I’ve owned the system for a few months now but sadly haven’t had much of a chance to put it to use as I’ve been busy with a few other things. I’ve done about 10-15 knives now, and the last few definitely turned out better than the first few. I’ve been able to get the knives very sharp by practical standards (they’ll cut just about anything with not much resistance), but I haven’t been able to push cut through paper, which is the benchmark I was going for. I haven’t yet had a chance yet to test out the strops with an increased pressure and less of an offset angle but I’m hoping to today and will report back with pictures and step by step methods if I still don’t get a good result.
Once you figure out what combination of angle adjustment and pressure works for you with the strops, I fully expect that your knives will push cut paper. Strops help tremendously with push cutting ability.
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