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So I have this old Kennametal Sharpening Stone shown here: enter image description here

I want to sharpen this dull edge shown here: enter image description here enter image description here

It was caused from learning mistakes which I am still doing, but would like a sharp knife, so I don't get discouraged by slow progress. So, before I start praticing my sharpening, I wanted to make sure what I have read up and learned is correct. I was going to use the stone with water on it and try to keep the knife at a 20 degree angle to remove the chips and regain the edge. Is this the correct high level process?

Also, I have recently learned about stropping, but I am unfamiliar with it. Is the concept of keeping a 20 degree angle the same? Also, if I have strips of leather (from deer) can I make a strop out of that? I can post a picture of the leather when I get home if need be.

Note: I have been using the quick sharpening tool with one coarse side and one fine side to try to fix it. Is this a cardinal sin?

Sorry if these question(s) are too broad. I'm new to wood working and would just like to start with good habits of keeping a sharp knife!

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TL;DR warning

would like a sharp knife, so I don't get discouraged by slow progress.

There's another issue here that's more important than slow progress, a sharp knife is safer in use. This seems paradoxical but blunt (and blunter) edged tools require more force to push through the wood, and this tends to lead more easily to accidents.

In addition blunt knives are more fatiguing to use.... by quite a large margin sometimes, depending on the hardness of the wood you're working with.

And last but not least a very sharp edge leaves a superior surface on wood, so there are visual advantages too for the woodworker.

I was going to use the stone with water on it

There's a chance that the stone you have there isn't really ideal for sharpening this type of tool, sorry but it's impossible to be more definitive without knowing more about Kannametal stones in general (very little info online) but more importantly that stone in particular which of course we can't know.

Judging from the stones I have used I think it's a silicon carbide honing stone but it's impossible to tell its grit rating from looking at it. And in addition to grit rating the binder or 'matrix' is a critical factor in how a stone works and the quality of the edge it can produce.

You'll have to test it out and see how it works firsthand.

Stropping after using the stone will go a long way to refining the edge created however good it is, if you discover the stone is a little too coarse you may find it beneficial to get a finer stone or diamond plate. Remember this is based on a guess of the stone's qualities, if it works well don't think you need to spend more money on further sharpening supplies to chase the elusive "perfect edge".

Note: I have a suspicion based on its appearance that the stone won't work well with plain water, so add some dishwashing liquid to it or use a light oil instead. If you want to try oil no need to buy anything specially marketed for honing, baby oil works very well, is cheap, completely non-toxic and can be bought anywhere.

and try to keep the knife at a 20 degree angle to remove the chips and regain the edge. Is this the correct high level process?

Basically yes. Honing angle is the most critical thing to maintain to achieve good, consistent results.

In practice it's not as easy as it sounds however. You will very likely find it difficult to hold the same angle consistently as you hone, almost everyone does when they start.

Something that will help you a lot in checking whether you're honing at too steep or too shallow an angle is to colour the bevel black with a felt tip/permanent marker. This way the portion of the bevel in contact with the abrasive is instantly visible as a shiny line against the black, rather than trying to see a shiny line against other shiny metal.

Also, I have recently learned about stropping, but I am unfamiliar with it. Is the concept of keeping a 20 degree angle the same?

Essentially yes. You don't have to be quite as religious about maintaining the exact angle but if you can do so that's great.

Details on what works best when stropping relate to numerous variables including the strop surface (leather*, cloth or bare wood/MDF) and whether you're using a bare strop or one loaded with an abrasive material (stropping compound, metal polish, diamond paste).

Note: remember when stropping to always use an edge-trailing technique. You never push an edge into a strop like you do on a honing stone, you always draw it backwards.


Be sure you look at the list to the right of this page under Related for much good information on sharpening that you might find useful.

Two additional Answers I'd like to draw your attention to:
How can I tell if wood turning (lathe) chisels are sharp?
When sharpening, how do I assess what grit to start on? (specifically the section Little and often, this has particular relevance to whittling and chip-carving knives)


*Type of leather may or may not matter. If you're using bare leather the type of leather matters a lot, but if you're applying some abrasive to the leather it doesn't matter much.

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    Good tip about coloring the edge with a marker. It will clearly indicate a lot of other problems with the sharpening stone or technique - a non flat stone will only remove the marker in some areas, an inconsistent angle to the blade will do the same. Seeing where the marker is still present will help in highlighting what's the problem and help the user to correct it – Eli Iser Feb 1 '18 at 12:17
  • Thank you for all of this great information! I tried sharpening last night with the stone using water. I did about 15 strokes on each side, and tested it out on my project. It seemed to cut better than before! So, I will implement your tips and hopefully I can actually finish my first project (started 1 year ago, and has just had very slow progress) – Cody Ferguson Feb 1 '18 at 16:43
  • @CodyFerguson Best of luck with the sharpening Cody. Sharpening is a journey, nobody should expect to do it well every time early on but you will get better at it over time if you stick to it. #1 thing is diligently holding to the correct angle(s) and the marker trick to see where you're actually abrading steel will prove a big help in honing at the edge or across the whole bevel as you want and not just at the shoulder of the bevel. – Graphus supports Monica Feb 2 '18 at 5:54
  • @CodyFerguson Oh and once you get to stropping if you have any queries on that which aren't covered in previous Q&As here don't hesitate to ask a new Question. As mentioned in some previous Answers shaving-sharp is about the minimum level of sharpness you want to aim for eventually, and you might be able to get that perhaps within the first week if everything is right. – Graphus supports Monica Feb 2 '18 at 5:58
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    @Graphus Okay, I will work on keeping the correct angle while using the marker trick! Thank you so much for your help! – Cody Ferguson Feb 5 '18 at 14:40
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Sharpening is a very broad topic with a lot of information out there. The main thing to keep in mind is that it's very difficult to ruin steel with hand sharpening - even the harshest mistakes can be re-ground and re-sharpened, costing only time. With power sharpening you can easily lose the temper of the steel, which is next to impossible to fix a home properly.

Sharpening a carving knife to 20 degrees is a common angle, and should work out fine. With practice you'll improve at keeping the angle constant.

The biggest suggestion is to invest in some fine grit stones. Typical coarse/fine stones you can find are extremely coarse when compared to typical grits used for sharpening woodworking edges tools. These are typically 220/400 (and sometimes even less), while at least 1000 grit is recommended for honing, with many going up to 8000 on stones and then polish with compounds at 30000 or higher grit. You'd be surprised how sharp steel can be with the proper progression of grits.

Stroping is quite different from sharpening. In sharpening, you are removing metal. In stroping, you align the burr (the microscopic edge left after sharpening), so the movement is always in one direction, from the cutting edge backwards. In sharpening, you can move the knife in both directions on the stone. Some people add polishing compounds to the strop leather, to further polish the edge. Stroping in general is a final touch, and you can achieve great results without it.

From personal experience, I use 600/1200 DMT diamond plate and 1000/8000 King water stone for sharpening and honing my chisels and striking knife. The 8000 stone leaves a mirror finish.

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    Also, once you've sharpened, stropping is all that is needed for quite some time to "resharpen" the blade. If you don't let it get too dull, but strop frequently when it begins to cut a little worse, then you can recover the cutting edge and continue working. With a little bit of experience, you'll feel the difference between a blade cutting well, and one cutting just okay. Use your strop to hone the blade, and you'll be back to cutting well. – Charlie Kilian Jan 31 '18 at 17:58
  • @CharlieKilian that's a very interesting piece of advice. I usually work with chisels, not knives, so my experience is going quite rapidly from sharp to (small) nicks, but I'll give frequent stroping a try. – Eli Iser Jan 31 '18 at 18:14
  • Depending on what you're doing with the chisels, it seems to work well for them, too. Obviously it'll work better with fine work than it would if you're pounding away with a mallet. But still, discovering this trick was transformational. Now I always keep the strop on my bench. – Charlie Kilian Jan 31 '18 at 21:38
  • This is very helpful! The stone was given to me by my grandpa (along with a buck knife) which is why I know nothing about the attributes of the stone. So, I will eventually invest in a finer grit stone as you suggest! – Cody Ferguson Feb 1 '18 at 16:47
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The type of the stone (the kind of abrasive it is composed of) is important to know. Broadly speaking, it could be natural stone (hard or soft Arkansas usually), synthetic (aluminum oxide or silicon carbide), or a water stone. I think given the name Kennametal, it's unlikely to be a water stone and is probably aluminum oxide or Silicon Carbide; I'd bet aluminum oxide. Those work better for me with oil rather than water. Mineral oil is what is sold as "honing oil" and is what I use. It's available from the drugstore (laxatives aisle) and other places; its sometimes used as a "finish" on wooden cutting boards.

Aluminum oxide stones can get glazed pretty easily if used without lubricant. If you are going to use water, best to add a few drops of dishwashing detergent.

If it's already glazed ("found" and "toolbox" stones always seem to be), your progress will be very slow. With a sharp stone you should be able to see the grinding of a single stroke (if you look closely). The stone's surface is restored by lapping, which also flattens the surface if done properly. A proper lapping plate is expensive, so if you're not yet in for the long haul, you might want to get some diamond sharpening wands (they come in a package and have a form-factor roughly like a shortened, double-thickness tongue-depressor. They work pretty quickly and last a while. Water lubes those fine. They're also convenient to handle for such a short blade.

  • Cinder blocks and paver stones can serve as decent lapping plates. Using circular motions will ensure a flat surface to the sharpening stone even if the paver isn't flat – Eli Iser Feb 1 '18 at 12:15
  • I attempted sharpening last night with the stone using water. It seemed to improve the sharpness, so I will try it with mineral oil instead. The stone was given to me by my grandpa which was stored in a leather pouch attached to a buck knife sheath. So, it may have been protected from being glazed. I will have to look into that further. Thanks for the advice! – Cody Ferguson Feb 1 '18 at 16:50
  • @CodyFerguson Glazing generally results from use (not storage), often by using without lubricant. More precisely, "glazed" means "worn dull" and/or "loaded" (with grinding swarf). Either way, the sharp points of the abrasive particles do not contact the work properly and material removal is slow. Lapping removes the swarf and exposes a new layer of sharp abrasive particles. Lubrication prevents swarf from building up and dull particles are broken off by grinding forces to reveal a sharp new particle. This extends the time between dressings/lappings. But all stones need lapping periodically. – scanny Feb 2 '18 at 21:56
  • @scanny Ah, okay. That makes a lot of sense! I while learn how to lap my stone as it would probably be best to start practicing with a good stone! Since, I have a limited budget and live in a small apartment, I will go with the paver stone suggested by Eli Iser. – Cody Ferguson Feb 6 '18 at 14:23

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