Sharpening question.

Lapedog

Lapedog

Joined
Dec 7, 2016
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So basically my question is in relation to raising a burr when sharpening.

Generally I don't let my knives get dull enough that any sharpening I do is much beyond a touch up. I find that when touching up my knives I get very good results from the sharpening mehod I use.

Here is a description of the method. Basically I hold the sharpmaker stones in one and and knife in the other. I match the angle on one side of the knife to the stone and do a stoke heel to tip. After just that one stroke I flip the knife over match the angle and do a stroke on the other side. Then I flip repeat, flip repeat again and again. So basically I am flipping the knife with each stroke which isn't really raising a burr. This works fine for touching up knives and even seems to work on some knives that have gone fairly dull.

However some knives seem stubborn. For example using this method I can get my Inkosi sharp but not as sharp as I would like. I know the problem isn't getting the angle right as I have tried the sharpie trick and am well practiced getting the angle right. (I wouldn't even be able to touch knives up if I didn't)

Will I get better results if I do strokes on one side long enough to raise a burr then flip and raise a burr on the other side? Btw I stick to my coarser stone for most sharpening only finishing up with the fine.
 
I've never tried that technique, but it would seem to me to be difficult to maintain a consistent angle and pressure. I sharpen freehand on DMT bench hones 99% of the time (1% being an ancient Black Arkansas stone which works great on high carbon steel blades), using a firm surface like a workbench. Can you try placing your hones on a steady table or workbench?
 
The way you mentioned is great for touchups. To know when we have exposed fresh steel and ground to the apex is the purpose of a burr. It lets you know to turn the knife over and raise the burr on the other side. This way you can be sure that both sides have ground enough for a fresh edge AND reached the apex--essentially forming a crisp intersection point of your two sides.

Once you have raised the full length heel to tip burr on one side and turned it over to repeat the process you have your edge. The rest is refinement.

After the initial burrs are done you remove it by putting the side with the visible burr against your stone at roughly double the sharpening angle. Then give a couple--2 or 3 usually does it--very light edge leading passes to remove it. Repeat the whole process for each progressively finer stone you use. The burr gets smaller and smaller the finer you go. then to finish after your finest stone, give about 10 edge trailing light strokes on your favorite strop. Use the same angle you did for sharpening. Don't overdo the stropping or you could compromise sharpness by turning the apex from a point into a rounded dome.

I go freehand like you most times and here is what I use: Atoma 140, DMT Coarse 325, DMT fine 600, Shapton glass 1k, SG4K, SG6K...I go all out sometimes! In a hurry though, I am more than happy to stop at DMT 600 fine and then a few strokes on a balsa strop loaded with 1 micron diamond paste or spray.

Note--I consider the Atoma the "big guns" of the repertoire; I only really need it if I beat my edge to s___. Otherwise, the 325 suffices quite nicely as a beginning point. The Atoma makes short work of re profiling and chips.

Remember--when you sharpen, 90% of the work is with your coarse stone.
 
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Think of it like a trapezoid vs a triangle. You can match the angles all day long, but if the two sides don't come together at a keen apex then it won't be sharp. A problem if there's a chip, roll or flat spot on the edge.

The method you describe is fine for basic touch ups, though I'd still recommend using the sharpmaker as designed, but raising a burr is the only way you're going to guarantee a full apex grind.
 
Ratman79 said:
The way you mentioned is great for touchups. To know when we have exposed fresh steel and ground to the apex is the purpose of a burr. It lets you know to turn the knife over and raise the burr on the other side. This way you can be sure that both sides have ground enough for a fresh edge AND reached the apex--essentially forming a crisp intersection point of your two sides.

Once you have raised the full length heel to tip burr on one side and turned it over to repeat the process you have your edge. The rest is refinement.

After the initial burrs are done you remove it by putting the side with the visible burr against your stone at roughly double the sharpening angle. Then give a couple--2 or 3 usually does it--very light edge leading passes to remove it. Repeat the whole process for each progressively finer stone you use. The burr gets smaller and smaller the finer you go. then to finish after your finest stone, give about 10 edge trailing light strokes on your favorite strop. Use the same angle you did for sharpening. Don't overdo the stropping or you could compromise sharpness by turning the apex from a point into a rounded dome.

I go freehand like you most times and here is what I use: Atoma 140, DMT Coarse 325, DMT fine 600, Shapton glass 1k, SG4K, SG6K...I go all out sometimes! In a hurry though, I am more than happy to stop at DMT 600 fine and then a few strokes on a balsa strop loaded with 1 micron diamond paste or spray.

Note--I consider the Atoma the "big guns" of the repertoire; I only really need it if I beat my edge to s___. Otherwise, the 325 suffices quite nicely as a beginning point. The Atoma makes short work of re profiling and chips.

Remember--when you sharpen, 90% of the work is with your coarse stone.
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So just so I have this straight the steps will be as follows.

First I use my coarser stone to raise a burr on one side. Flip the knife and then raise the burr on the other side. Now I use a couple high angle strokes to knock that burr off (so I only use these high angle strokes on the side where the burr now is? Or on both sides?)

Now I switch to a finer stone and repeat the same process, again and again for each progressively finer stone.

OR

Do I raise burr on one side, flip raise burr on other side, then switch to a finer stone flip knife to original side raise burr again, flip the knife raise a burr on the other side (continued until the finest stone at which point I remove the burr with a few high angle strokes...again do I apply these high angle strokes on just the side the burr is on or on both sides)

I guess what I'm asking is do I have to remove the burr with the high angle strokes each time before switching to a finer stone?

TLE Sharp, I just found that using the Sharpmaker as designed the angles it came preset with (30 deg and 40 deg inclusive) did not match exactly enough with what most the factory edges were angled at. This meant that I ended up having to try to grind the knives to match the sharpmaker angles, rather than using the stones to match the angle of the knives. Also I honestly find it hard to be sure the knife is going down the sharpmaker stones completely vertical when using them in that V set up in the jig. I found that if I just use the feeling of the edge laying flat on the stone I could get a new knife, and by touching it up get it screaming sharp way past the factory edge.
 
For what it's worth you don't need to be completely vertical on the Sharpmaker, you just need to make sure the angle is consistent throughout the sharpening process. Traditional stones are great though, I don't think you can beat them until you get up into the EdgePro/Wicked Edge/etc. realm.
 
You don't have to repeat the entire burr process for each progressively finer stone but it is a good idea. If you have a loupe, you can check as you grind to see the stone's scratch pattern progress. The idea is to make sure you reach the apex with each stone, completely replacing the old scratch pattern with the new one. Keep in mind, you can have a tiny burr that can only be seen under bright light/loupe--it does not have to be a big burr.

You do not have to remove the final burr before going to the next stone--just start your grinding on the other side. Establish your scratch pattern/burr and do the other side.

Just a quick note-when knocking off the burr, usually an even amount of strokes per side does the trick. The reason you hit both sides is so you actually get rid of it and not merely push it to the other side.
 
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Thank you guys very much for the tips. Hopefully I'll be able to get this thing right. I don't want to have to send it in to the only sharpener in my city who is worth sending knives to. Sometimes you have to wait two weeks to get your knife back.

Nothing is more frustrating than sitting trying to get a knife sharp for hours and hours and hours then trying again the next day, then again the next day and only getting it sharp enough to slice paper barely.
 
I just noticed that the troublesome knife in question is an Inkosi. Don't take what I'm saying as gospel, because I'm new to the CRK world, but I've seen a lot of people say that it takes quite a while to profile their knives to where the Sharpmaker works well on them, and I'm struggling a bit with my new Sebenza as well. I generally use a Lansky system to profile knives and then the Sharpmaker and a strop for finishing and maintenance, but taking the Lansky to a $350 knife scares the crap out of me.
 
The funny thing is on my Sebenzas I've been able to get them razor sharp with my sharpmaker stones. Also note that I don't use the sharpmaker as designed for that very reason. Most knives are not 30 or 40 degrees inclusive which are the only two settings on the sharpmaker. I find it easier to match the angle to the stone freehand rather than grinding the knife to be 30 or 40 so it matches the sharpmaker setting.

However as all CRK knives come with convex edges it makes it a pain to get my CRKs ground where I can feel the edges laying flat on the stone. I have to kind ofnget rid of that convex edge. The Sebenzas were super easy for some reason the inkosi is being a real pain.
 
Another question about removing the final burr. I heard you could actually just make a few cuts into wood to knock that final burr off.
 
^^You could try the wood if you like--some have had success w/ it. It is mainly to get rid of the real tiny pieces of burr that may stubbornly hang on. Removing the full length burr is best done by raising the angle and lightly grinding it off. Also-- if you have a leather strop you could give a few passes with a coarser compound to remove the burr. (black compound)
 
I'm not coordinated enough to use a sharpmaker either. Always got terrible results. It's me, not the sharpmaker though.

Try clamping your knives in a horizontal vice if you can. That way you can focus on just the stone's angle. Might be a good way to refine your technique.

As for the burr; I always recommend stropping after you sharpen a knife. Regardless of technique, grit level, etc. There's all sorts of stuff you can use, it doesn't have to be leather.
 
OP: it is most likely the blade geometry of that Inkosi which is giving you fits on the Sharpmaker, although I have never owned an Inkosi but had owned a large 25 which I believe to essentially share the same blade geometry! I was having similar issues with my Wilson Combat Umunmzaan (Star-Tac) which outta box couldn't cut sheet (yes, both literally and figuratively speaking!). I just said fudge it and went freehand with the Fallkniven diamond / sapphire ceramic stone and then either green compound strop or the Spyderco UF306 ceramic plate. Still not hair whittling sharp, but now slices through phonebook paper and getting closer to my Spyderco Millies in terms of sharpness. I used the diamond side of the plate to straighten that convex factory edge which I hated. The Zaan's blade geometry is even a fatter pig as compared to your Inkosi...
 
By the way thank you everyone. Raising a burr on one side and flipping it worked for me. The knife is now slicing receipt and phone book as well as printer paper.

I want to say this, all in all I am glad CRK runs their knives abit softer, that took forever. Damn S35vn can be a bear to sharpen if it has gotten fairly dull. Took me forever on the stones.

Thank you guys so much.
 
Good stuff ^^

I'm glad you got it dialed in! I know it can be nerve-wracking to grind away on such a nice (and costly) knife. We have all been there at one point or another. I have found that the DMTs or any competently made diamond stones are excellent for forming the initial edge--especially when your knife is beyond the reach of a mere "touch up." You can continue up the grit ladder with the diamonds exclusively, or you could transition to waterstones etc. also. I start with diamond plates because they cut all steels well and do it quickly.

For waterstones, as I mentioned, I have a few Shapton Glass (SG) stones (benchstones and EdgePro sized) which are wonderful for CPM steels. Even a particularly coarse SG like 220 grit/ 60 microns creates a very manageable burr and quite quickly too. There is a 120 grit stone that would probably be even faster! They are great quality *fast* cutters. I have tried Chosera stones also but the Shaptons are less fussy--no soaking required, just slick up the surface and go. They are faster than Choseras too.

Drawbacks are cost and lapping. While you can lap SG stones on an XX coarse DMT up to 500/30 microns, they recommend a proprietary plate that is expensive being almost $400. Realistically, I have lapped my 220 and 500 on the XXC DMT and 1k and up on a DMT 325/coarse with fine results. Higher than 4k or 6k they get cranky. I have used a DMT 600/fine with good results. Atomas are great for lapping but they are close to 90 per plate. The quality is amazing and if you are not abusing them, they can go for a while.

Sorry about writing a book! I just wanted to help you out in case you were thinking of expanding your sharpening supplies inventory.
 
Ratman79 said:
Good stuff ^^

I'm glad you got it dialed in! I know it can be nerve-wracking to grind away on such a nice (and costly) knife. We have all been there at one point or another. I have found that the DMTs or any competently made diamond stones are excellent for forming the initial edge--especially when your knife is beyond the reach of a mere "touch up." You can continue up the grit ladder with the diamonds exclusively, or you could transition to waterstones etc. also. I start with diamond plates because they cut all steels well and do it quickly.

For waterstones, as I mentioned, I have a few Shapton Glass (SG) stones (benchstones and EdgePro sized) which are wonderful for CPM steels. Even a particularly coarse SG like 220 grit/ 60 microns creates a very manageable burr and quite quickly too. There is a 120 grit stone that would probably be even faster! They are great quality *fast* cutters. I have tried Chosera stones also but the Shaptons are less fussy--no soaking required, just slick up the surface and go. They are faster than Choseras too.

Drawbacks are cost and lapping. While you can lap SG stones on an XX coarse DMT up to 500/30 microns, they recommend a proprietary plate that is expensive being almost $400. Realistically, I have lapped my 220 and 500 on the XXC DMT and 1k and up on a DMT 325/coarse with fine results. Higher than 4k or 6k they get cranky. I have used a DMT 600/fine with good results. Atomas are great for lapping but they are close to 90 per plate. The quality is amazing and if you are not abusing them, they can go for a while.

Sorry about writing a book! I just wanted to help you out in case you were thinking of expanding your sharpening supplies inventory.
Click to expand...


I use an 8" diamond disk from Kingley North for lapping now. The one I am currently using is 180 mesh, I'll get a 100 mesh if I ever buy a replacement - there is a wide range of grit size available. These cost about $50-60, about half of that if you only get the top plate and glue it to something flat. Made for rotary polishers, just drop a rag in the sink, set it on top and run a trickle of water while manual lapping.

They are no good for sharpening until you get to about 1200 mesh or finer, but the diamond bond is plated extremely strong and these things last. I have lapped/flattened a Spyderco fine, several India stones, Crystalon stones, Arkansas, and also polished facets on solid quartz and a number of other semi-precious stones and this particular lap is just starting to slow down. Plus, being round it has a lot of surface area.
 
Good to know thank you! ^^

I am going to check that out. It has to be quite hearty indeed to mess with quartz crystal. Nice find
 
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