I'm new at this so please excuse my dumb question.
I just bought a new sharpmaker knife sharpner. It came with a VCR tape that says that even though the factory angles are ground at 30 degrees the user should sharpen his knives at 40 degrees for the best results.
My question is what this means? Is the factory not putting the best edge on the brandnew knives or was the 40 degree comment misspoken?
Bottom line is, use 30 or 40 degrees when sharpening?
I have a sharpening question?
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dragn_flame
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Sal explains that pretty well in the video: Spyderco puts a 15 deg. bevel on their blades to save you a ton of work. By working on a 20 deg. setting you ensure that you are really working on the edge and refinement and sharpening is very quick. Its also called a microbevel. If you were working on the same angle as the primary edge, not only would you have to remove more metal, but every time you don't hold the knife perfectly upright but tilt towards the rods, you are not working on the edge at all.
Working with two angles is a common technique, which is also often used to remove stubborn burrs.
Best you just follow the instructions of the video.
Working with two angles is a common technique, which is also often used to remove stubborn burrs.
Best you just follow the instructions of the video.
remeber if its v10 or s30v, you really aint got to worry. Its very hard to get them to chip, i keep all my knives at 30°. They seem sharper like that.
My knives need to be so sharp that i can take a peice of computer paper and run the knife throgh it with its own weight, Then you know the **** is just to sharp.
also if you ever cut yourself, The sharper the blade the less it hurts.
My knives need to be so sharp that i can take a peice of computer paper and run the knife throgh it with its own weight, Then you know the **** is just to sharp.
also if you ever cut yourself, The sharper the blade the less it hurts.
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Devils_Advocate
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30, 40 degrees?
I agree with HoB and 999.
People who think they know it all are especially annoying to those of us who do.
Thanks to all.
As I understand your comments the 30 degree initial grind from the factory makes it easier for the knife to cut through material (less friction on the blade). The 40 degree sharpening grind flares the grind out by another 10 degrees which makes it a stronger edge.
I quess what I still don't understand is why the factory doesn't ship the knife with the 40 degree stronger edge already on it?
As I understand your comments the 30 degree initial grind from the factory makes it easier for the knife to cut through material (less friction on the blade). The 40 degree sharpening grind flares the grind out by another 10 degrees which makes it a stronger edge.
I quess what I still don't understand is why the factory doesn't ship the knife with the 40 degree stronger edge already on it?
how I see it is this. The 40 really isnt a strength issue, though it might help a little bit you shoulnt have problems.
Most sharpening instructions have recomended you "hone" at a higher angle than the normal edge bevel. This is primarily to make it easier, but over time, you will end up grinding the initial bevel away entirely. I dont think this is likely for most useres, but IDK.
I try to keep all of my knives around 30, but since I use a stone by hand, its not exact by any means. I do "micro bevel" but this is only very minor, just a few strokes on the finer setting. When I go to strop I work a little to convex the edge (not an actual convex edge, just microscopically soften the corners of the bevels and make sure the entire edge is polished)
You can just use the 30 deg setting if you want. The 40 will make it easier to sharpen, and if you get the the point where your bevel is too thick, instead of doing the leg work, you can send the knife to spyderco with 5 bucks for return shiping and I think they will restore the factory edge (though I dont know for sure, they may just use the sharpmaker like they do when you take a knife into the spyderco factory outlet for free sharpening).
I have heard of people getting the best results sharpening at 30 deg all the way up to the white flats as the vid describes, then moving to 40 deg white flats and do 10 strokes on either side at that setting. The 10 strokes will make a microbevel which does a few things. It removes the burr, which is excess metal built up on the edge by sharpening. It also makes the edge a bit stronger and durable.
You should also tailor your edge to your task. If you are doing a bunch of really heavy cutting, like a bunch of cardboard wiht staples that murphy will make your edge hit, regularly, the 40 degree setting is better for everythng. If you are doing light tasks such as opening paperboard, the occational package, mail, and cutting food, 30 will suit you better. You could probably go thinner actually.
Most sharpening instructions have recomended you "hone" at a higher angle than the normal edge bevel. This is primarily to make it easier, but over time, you will end up grinding the initial bevel away entirely. I dont think this is likely for most useres, but IDK.
I try to keep all of my knives around 30, but since I use a stone by hand, its not exact by any means. I do "micro bevel" but this is only very minor, just a few strokes on the finer setting. When I go to strop I work a little to convex the edge (not an actual convex edge, just microscopically soften the corners of the bevels and make sure the entire edge is polished)
You can just use the 30 deg setting if you want. The 40 will make it easier to sharpen, and if you get the the point where your bevel is too thick, instead of doing the leg work, you can send the knife to spyderco with 5 bucks for return shiping and I think they will restore the factory edge (though I dont know for sure, they may just use the sharpmaker like they do when you take a knife into the spyderco factory outlet for free sharpening).
I have heard of people getting the best results sharpening at 30 deg all the way up to the white flats as the vid describes, then moving to 40 deg white flats and do 10 strokes on either side at that setting. The 10 strokes will make a microbevel which does a few things. It removes the burr, which is excess metal built up on the edge by sharpening. It also makes the edge a bit stronger and durable.
You should also tailor your edge to your task. If you are doing a bunch of really heavy cutting, like a bunch of cardboard wiht staples that murphy will make your edge hit, regularly, the 40 degree setting is better for everythng. If you are doing light tasks such as opening paperboard, the occational package, mail, and cutting food, 30 will suit you better. You could probably go thinner actually.
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dialex
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Welcome aboard.
30° means a steeper angle, thus the cutting ability of the knife is improved. Unfortunately, there are steels and steels, and some of them are too soft to hold an edge too much if sharpened at 30°. Spyderco is known for making sharp knives out of the box, and they can afford sharpening them all at 30°. However, when it comes to the regular ELU, they give him - with the 204 - the opportunity of choosing wheather he / she wants an edge that is sharper (30°) or one that stays longer (40°).
These said, from my personal (and limited) experience, I've seen that steels like VG-10, CPM-440V (S60V) or S30V, or even ATS-55 have no problem in maintaining an edge at 30°, while the AUS-6 (AUS-8) and ATS-34 need to be sharpened at 40°.
30° means a steeper angle, thus the cutting ability of the knife is improved. Unfortunately, there are steels and steels, and some of them are too soft to hold an edge too much if sharpened at 30°. Spyderco is known for making sharp knives out of the box, and they can afford sharpening them all at 30°. However, when it comes to the regular ELU, they give him - with the 204 - the opportunity of choosing wheather he / she wants an edge that is sharper (30°) or one that stays longer (40°).
These said, from my personal (and limited) experience, I've seen that steels like VG-10, CPM-440V (S60V) or S30V, or even ATS-55 have no problem in maintaining an edge at 30°, while the AUS-6 (AUS-8) and ATS-34 need to be sharpened at 40°.
The mind commands the body and it obeys. The mind orders itself and meets resistance.
Thanks again for all your help and suggestions. I really appreciate all the responses.
I understand what you are saying about different steels holding up better with different grinds and micro edges and stropping.
However you should have a Sharpmaker and have watched the Spyderco video in order to understand my question.
http://spyderco.com/catalog/details.php?product=99
As I hear Sal in the video (and read the Sharpmaker instructions) say to sharpen (using their own Spyderco Sharpmaker sharpener) at 40 degrees unless the edge is very dull then you use a two step process. You first sharpen at 30 degrees (what I call reprofiling) and then you finish at 40 degrees using the various ceramic rods. If the Spyderco steel is that good that it can hold a 30 degree edge for normal use I wonder why that isn't mentioned. All the tests in the video use Spyderco knives to illustrate the sharpening technique which is a good one.
With a Sharpmaker it is just as easy to sharpen at 30 degrees as 40 degrees. You just plug the the sharpening rods into different holes. The video and instructions don't imply that the 40 degree setting is just to hone and deburr the blade. They tell you to do 20 strokes per edge.
I don't have any problems with 40 degrees, it is what I would use anyhow. I'm just wondering why they come from the factory at 30 degrees yet their owner/boss in his video and in there instruction manual says to sharpen using his brand of sharpener at 40 degrees.
I mean if it is a marketing strategy to sell really sharp edged knives why not put a real think razor edge on it. It will definately shave hair and cut paper. However in the real world of knives it won't be worth a flip after a couple of cuts until you resharpen it to the best proper angle. Who was it that came up with the idea that shaving hair and paper was the best way to guage sharpening for a working pocket knife?
I'll shutup now. My curiousity is running away with me.
Anyone out there from Spyderco managment care to comment?
I understand what you are saying about different steels holding up better with different grinds and micro edges and stropping.
However you should have a Sharpmaker and have watched the Spyderco video in order to understand my question.
http://spyderco.com/catalog/details.php?product=99
As I hear Sal in the video (and read the Sharpmaker instructions) say to sharpen (using their own Spyderco Sharpmaker sharpener) at 40 degrees unless the edge is very dull then you use a two step process. You first sharpen at 30 degrees (what I call reprofiling) and then you finish at 40 degrees using the various ceramic rods. If the Spyderco steel is that good that it can hold a 30 degree edge for normal use I wonder why that isn't mentioned. All the tests in the video use Spyderco knives to illustrate the sharpening technique which is a good one.
With a Sharpmaker it is just as easy to sharpen at 30 degrees as 40 degrees. You just plug the the sharpening rods into different holes. The video and instructions don't imply that the 40 degree setting is just to hone and deburr the blade. They tell you to do 20 strokes per edge.
I don't have any problems with 40 degrees, it is what I would use anyhow. I'm just wondering why they come from the factory at 30 degrees yet their owner/boss in his video and in there instruction manual says to sharpen using his brand of sharpener at 40 degrees.
I mean if it is a marketing strategy to sell really sharp edged knives why not put a real think razor edge on it. It will definately shave hair and cut paper. However in the real world of knives it won't be worth a flip after a couple of cuts until you resharpen it to the best proper angle. Who was it that came up with the idea that shaving hair and paper was the best way to guage sharpening for a working pocket knife?
I'll shutup now. My curiousity is running away with me.
Anyone out there from Spyderco managment care to comment?
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Simple Man
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- Location: Kentucky
I think it is more of a broad End Line User maintenence issue. With the edge shipped at a 30° angle, sharpening to 40° by the typical ELU will take a LONG time to bring the whole bevel down to 40°. Most will never have a problem sharpening the working edge of the knife using the 204. If it was shipped with a 40° edge, the ELU would already be behind and may have problems sharpening the working edge if they were say just 1° off. There are a lot more ELU's out there that don't know about edge angles and don't care to. They just know that Spyderco's work well and they get sharp by doing what Spyderco says, either that or thay rub them on that stone grandad gave them and it works "good enough". Personally, I have reprofiled my Millie down to about 22°-25° inclusive and strop it on leather or cardboard without compound. When it actually needs sharpening I use the 30° and have had no problems.
Bottom line. If you are just a general ELU, 40° is "good enough". If you are like most of the folks around here, afficianados, experiment with it until you find what works best for you (usually screaming stupid sharp). :D :D
Bottom line. If you are just a general ELU, 40° is "good enough". If you are like most of the folks around here, afficianados, experiment with it until you find what works best for you (usually screaming stupid sharp). :D :D
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Romans 8:31 ....If God is for us, who can be against us? - <><
The Spyderco hole is a rotating mechanical assembly of one part.
".....tractors don't have to look like Ferraris" -Sal
The Spyderco hole is a rotating mechanical assembly of one part.
".....tractors don't have to look like Ferraris" -Sal
If the Spyderco folks want the 30 degree edge sharpened to 40 degrees how come they don't sell it like that? What this means to me is that everyone who buys a brandnew Spyderco knife should (according to their instructions) immediately sharpen it to 40 degrees before using it.
That doesn't make any sense to me but that's what the instructions for the Sharpmaker say to do. Sharpen to 40 degrees!
That doesn't make any sense to me but that's what the instructions for the Sharpmaker say to do. Sharpen to 40 degrees!
d.g.g wrote:If the Spyderco folks want the 30 degree edge sharpened to 40 degrees how come they don't sell it like that? What this means to me is that everyone who buys a brandnew Spyderco knife should (according to their instructions) immediately sharpen it to 40 degrees before using it.
That doesn't make any sense to me but that's what the instructions for the Sharpmaker say to do. Sharpen to 40 degrees!
read the above posts, your question is already answered,
yes s30v will hold an edge at 30°. You wont have to worry.
I am probrolly the person on this forum who uses his knives to the Limits everyday. I find it fun.
I have never had a problem with 30°,I find it cuts alot faster than 40°.
2 days ago, I cut down a full tree at the trunk. It was about a 4" diameter. When I broght the knife home, It was hot at ****, But would still cut throgh paper as well as before the tree, so the s30v holds an endge very well at 30°
I am probrolly the person on this forum who uses his knives to the Limits everyday. I find it fun.
I have never had a problem with 30°,I find it cuts alot faster than 40°.
2 days ago, I cut down a full tree at the trunk. It was about a 4" diameter. When I broght the knife home, It was hot at ****, But would still cut throgh paper as well as before the tree, so the s30v holds an endge very well at 30°
It's only the *very* edge that is at 40°. That part will likely be so small as you cannot even see it at that angle. It is for maintenence of the scary sharpness rather than anything else.
This is not to say that sharpening at 40° is better or worse, it's just the easiest way (IMO) to consistently put a good edge on a 30° bevel.
This is not to say that sharpening at 40° is better or worse, it's just the easiest way (IMO) to consistently put a good edge on a 30° bevel.
Dave.
That is not true. After 20 strokes per side you can definately see the 40 degree angle. This is not just a lite deburring (if you sharpen according to Spyderco's instructions). You are instructed to give it 20 strokes on the angle of the rod and 20 on the flat. Trust me, it is not a microscopic edge once you follow the Sharpmaker's instructions.999 wrote:It's only the *very* edge that is at 40°. That part will likely be so small as you cannot even see it at that angle. It is for maintenence of the scary sharpness rather than anything else.
This is not to say that sharpening at 40° is better or worse, it's just the easiest way (IMO) to consistently put a good edge on a 30° bevel.
Look at this knife its at a 30 degree angle
See how the whole thing is shepaed like a V.
when you have a 30 degree and then sharpen it to a 40, it makes a mirco bevel 40 degree edge into that one. I aint got no pics of it because all my knives are at 30 degrees,
I aint got the little book either, I cant find it,. But there should be pictures in there of what it looks like,
Read this
http://home.nycap.rr.com/sosak/convex.htm
It helps to explain
See how the whole thing is shepaed like a V.
when you have a 30 degree and then sharpen it to a 40, it makes a mirco bevel 40 degree edge into that one. I aint got no pics of it because all my knives are at 30 degrees,
I aint got the little book either, I cant find it,. But there should be pictures in there of what it looks like,
Read this
http://home.nycap.rr.com/sosak/convex.htm
It helps to explain
Well, the strength of an edge depends largely what you want to cut. S30V and VG-10 can support very low angles just fine, even the "older" super steels will do that, just ask Vampyrewolf about his Dragonfly which is ATS-55. However, if you drop your knife into the kitchen sink, run it through the dishwasher or start digging with it or cut wooden planks with nails, you will easily chip out the blade. Equally, even if you cut on a wooden board (which isn't the problem) but at the end of the cut twist your knife so that you have lateral pressure on the edge it might chip.
Having said that, cutting ability is in many cases not so much determined by the edge angle but by the material that has to be displaced. In cardboard your entire blade is stuck in the material to be cut, same with meat or a carot. Shaving is a different case. When ever the blade has to displace material, a large part of the cutting resistance comes from the work of displacement. The thinner the blade is the better it will cut. Even a blunt, and thin knife will appear to cut more easily than a thick, sharp one. But the closer you get to the edge the blade becomes progressively thinner, but how quickly the blade thickness changes depends on the angle. If you keep the blade at 5 deg included all the way to the edge, the blade may be less than a 1/1000 of an inch thick as far as 0.1 inches into the blade....very fragile. But if you keep 5 deg. included until the blade is 0.1 inches thick and then quickly (steeply) taper down to the edge at lets say 40 deg. included, the the part of the blade that is less than 1/1000 of an inch thick will be only 1/1000 of an inch deep and will be supported by thicker material. Yet the overall profile of the blade is still very thin and displaces very little material. That is the concept behind a standard full flat grind with edge bevel. Of course you can add another step on it for the same reason and go from 5 deg, to 30 deg to 40 deg on the final step. This will maximize the edge strength while sacrificing practically nothing in cutting ability.
On last word on edge strength: Every edge will dull, when I say "weak edge" that has nothing to do with the steel not supporting the edge. Its just common sense, the thicker the edge the longer it will hold. The blade (every blade) is so thin at the edge that the edge will often roll over despite the fact that the material is 60 Rc. The thicker the edge the slower this will happen but the ultimate sharpness will be less. It is mainly a matter of personal choice where your trade off is. If you are chopping wood you might want something like 50 or even 60 deg included. If you are careful and cut only soft materials, you can probably drop down to 20 deg. included. The angles that Spyderco suggests are the ones that they feel give you the best trade off between longevity and performance. And again the double bevel is a mater of convenience to you.
The 30 deg setting on the sharpmaker is for backbeveling. If you continue to sharpen at 40 deg. eventually you are making major changes to the edge geometry which will turn into a 40 deg bevel and you lose the benefits of the double bevel. So every once in a while you should sit down and backbevel so that the main geometry remains a 30 deg. But you don't have to do that all the way to the edge.
Sorry, I am a bit in a rush and the thoughts above are just my rambling.
Having said that, cutting ability is in many cases not so much determined by the edge angle but by the material that has to be displaced. In cardboard your entire blade is stuck in the material to be cut, same with meat or a carot. Shaving is a different case. When ever the blade has to displace material, a large part of the cutting resistance comes from the work of displacement. The thinner the blade is the better it will cut. Even a blunt, and thin knife will appear to cut more easily than a thick, sharp one. But the closer you get to the edge the blade becomes progressively thinner, but how quickly the blade thickness changes depends on the angle. If you keep the blade at 5 deg included all the way to the edge, the blade may be less than a 1/1000 of an inch thick as far as 0.1 inches into the blade....very fragile. But if you keep 5 deg. included until the blade is 0.1 inches thick and then quickly (steeply) taper down to the edge at lets say 40 deg. included, the the part of the blade that is less than 1/1000 of an inch thick will be only 1/1000 of an inch deep and will be supported by thicker material. Yet the overall profile of the blade is still very thin and displaces very little material. That is the concept behind a standard full flat grind with edge bevel. Of course you can add another step on it for the same reason and go from 5 deg, to 30 deg to 40 deg on the final step. This will maximize the edge strength while sacrificing practically nothing in cutting ability.
On last word on edge strength: Every edge will dull, when I say "weak edge" that has nothing to do with the steel not supporting the edge. Its just common sense, the thicker the edge the longer it will hold. The blade (every blade) is so thin at the edge that the edge will often roll over despite the fact that the material is 60 Rc. The thicker the edge the slower this will happen but the ultimate sharpness will be less. It is mainly a matter of personal choice where your trade off is. If you are chopping wood you might want something like 50 or even 60 deg included. If you are careful and cut only soft materials, you can probably drop down to 20 deg. included. The angles that Spyderco suggests are the ones that they feel give you the best trade off between longevity and performance. And again the double bevel is a mater of convenience to you.
The 30 deg setting on the sharpmaker is for backbeveling. If you continue to sharpen at 40 deg. eventually you are making major changes to the edge geometry which will turn into a 40 deg bevel and you lose the benefits of the double bevel. So every once in a while you should sit down and backbevel so that the main geometry remains a 30 deg. But you don't have to do that all the way to the edge.
Sorry, I am a bit in a rush and the thoughts above are just my rambling.