Where To Sharpen Knifes

[nokia]

Blinky,

Thank you for the very detailed instructions on how to sharpen a knife.

Do you normally sharpen your own knives?

Firstly i need a clamp to hold the stone.

Secondly I think each knife has different basic & final angles.

Lastly, its not easy to maintain the same angle after many strokes.

Hey CM folks,

what do you normally do with your blunt knives? Throw them away?

Or your knives are never blunt?

Cheers!

Hey folks,

thank you for all your interesting answers.

I can get a stone or a steel but the problem is that it's difficult to get the sharpening angle right.

Sometimes, the knife gets sharper, othertimes, more blunt.

Alternatively, i could get purchase a few more new knives instead?

Cheers!

There are few tools more dangerous than a dull knife! It'll slide when you want it to cut, and it'll cut when it stops sliding--usually when it hits your hand. Ask ten different people how they sharpen their knives, however, and you may get ten different answers. Not only that, but each of these ten methods are all sworn to be the best by ten venerable trail guides from ten mountain towns (who've all been sharpening knives since they were knee-high to a carpenter ant and don't you forget it buddy). What's a poor soul with a dull knife to do? You can start with this tutorial, which will lead you out of the tangled thicket of knife-sharpening opinions.

Choose your stone

First, there's the question of whether or not to use a liquid on the sharpening stone. A fiery debate rages on this issue, and you'd better figure out which side you're on, so you're not mistaken for the enemy and accidentally shot. Some stones are marketed as specifically for wet and dry uses, so keep the following points in mind as you shop around.

One school of thought insists that using oil, water or saliva helps "float" the tiny metal shavings away from the stone when the blade is being sharpened.

The other camp demands that using any type of liquid just clogs up the pores of the stone (which ruins the stone forever) and only polishes the blade, rather than grinding it.

The method below works with both dry and wet stones.

Recreate the basic edge

If you were to peer at the point of a nicely sharpened, multi-purpose knife blade, it would look something like Figure 1. You'll notice that the blade is actually beveled to form the final edge, but you won't create that bevel just yet. First, you'll form the basic edge, which is a little simpler in shape, as we see in Figure 1A.

One of the key points of knife-sharpening is maintaining constant angles between the blade and the stone. There are two: the angle between the blade and the edge of the stone, and between the blade and the surface of the stone.

Place your flat, medium-grit stone on the table in front of you. Lay the blade flat on the stone at a 45 degree angle, as shown in Figure 2. This 45 degree angle is the first of two angles.

Grasp the knife by the handle. With your index finger along the back of the blade, raise the blade off the surface of the stone at a 20 degree angle, as shown in Figure 3. This is the second angle.

Keeping the edge of the blade in contact with the stone, firmly and carefully draw the knife towards you. This action will grind the blade from hilt to point. Maintain the 45 degree angle, and the angle that you've raised the blade off the stone.

Apply medium to light pressure as you're drawing the edge across the stone. (For the sake of comparison, zero pressure would have the knife blade resting on the stone without you touching it.) Apply a little pressure or a bit more, depending on how old the knife is, how many times you've sharpened it, and the current condition of the edge. A very dull edge will require more pressure.

Turn the knife over, and repeat the process. If you keep the knife in the same hand, you'll be pushing the blade away from you this time. It's important to maintain the same angles on both sides of the blade. Go slowly and alternate strokes on the stone until each side of the blade has been stroked several times. A very dull knife will need a few more strokes than a better kept one.

Create the final bevel

Now that you have a basic edge on the blade, it's a time to create the final bevel. This will strengthen the edge, so that it stays sharp longer and is less prone to be damaged by everyday use. You'll create the bevel simply by repeating Step 1, with two modifications: use a fine-grit stone, and raise the blade a bit higher off the stone (the second angle) when you draw it across.

Place your flat, fine-grit stone on the table in front of you, and lay the blade flat on the stone at a 45 degree angle, as you did before.

Grasp the knife by the handle. With your index finger along the back of the blade, raise the blade off the surface of the stone at a slightly greater angle than before--maybe 25 to 30 degrees. See Figure 4.

Keeping the edge of the blade in contact with the stone, firmly and carefully draw the knife towards you. This action will grind the blade from hilt to point. Hold the 45 degree angle, and the angle that you've raised the blade off the stone, as constant as possible. Again, apply medium to light pressure as you're drawing the edge across the stone.

Turn the knife over, and repeat the process. Alternate strokes again until each side of the blade has been across the stone several times--about five strokes for each side should suffice. The pressure that you apply while drawing the blade across the stone should get progressively lighter with each stroke.

At this point you should have a pretty sharp knife. You can test it by holding a piece of paper vertically, and drawing the blade across the edge and down. A sharp knife will cut the paper.

And next you may choose to do a course in basic first-aid.

[nokia]

Ok folks,

i managed to successfully sharpen 2 meat cleavers to my missus' approval using Blinky's instructions at 20'c angle.

Thanks Blinky

[jaideeguy]

Amazing nokia!!!!

next, you'll want to know how to open a coconut, right??

me, I want to know how to operate a 'nokia'.....mine has me baffeled, as when I get a call, I press the red button and no one is there....every time. Maybe someone is sending me crank calls??

[Blinky Bill]

Ok folks,

i managed to successfully sharpen 2 meat cleavers to my missus' approval using Blinky's instructions at 20'c angle.

Thanks Blinky

You are more than welcome nokia.

But I must admit I am wondering whether you are either a complete moron or someone merely taking the piss. Still not too sure, can you offer some evidence that you are the latter?

[cmsally]

Ok folks,

i managed to successfully sharpen 2 meat cleavers to my missus' approval using Blinky's instructions at 20'c angle.

Thanks Blinky

You are more than welcome nokia.

But I must admit I am wondering whether you are either a complete moron or someone merely taking the piss. Still not too sure, can you offer some evidence that you are the latter?

:D

If sharpening knives is such a humongous task, trying to sharpen the garden shears should produce some interesting results.

Watch out CM Ram casualty, here he comes.

[nokia]

Ok folks,

i managed to successfully sharpen 2 meat cleavers to my missus' approval using Blinky's instructions at 20'c angle.

Thanks Blinky

You are more than welcome nokia.

But I must admit I am wondering whether you are either a complete moron or someone merely taking the piss. Still not too sure, can you offer some evidence that you are the latter?

Haha... Let's have a New Year laugh on me!!! Blame it on the coconuts...

[zzdocxx]

Ok folks,

i managed to successfully sharpen 2 meat cleavers to my missus' approval using Blinky's instructions at 20'c angle.

Thanks Blinky

How the heck do you know that it is precisely 20 degrees, and then on top of that hold it steady there?

On a related note, from my research on the net, I learned that for these "Asian" style knives, eg. "Santoku", the edge profile is 15 to 18 degrees, rather than the 20 to 22 for western style.

A friend, his parents have a restaurant with a grinding wheel for knife sharpening, it has an adjustable guide.

Of course I have sharpened knives "freehand" on a stone, but I mean to really do it exactly right, I don't know about that.

[FolkGuitar]

Here's an easy way to maintain the constant angle needed for sharpening. (Note that I say 'constant angle' rather than a specific number. Reason being, the exact number isn't all that important other than to say for a thinner slicing blade such as for fish filets use a smaller angle. For cutting veggies use a larger one. For chopping with a cleaver, a larger one still. )

Take a plastic pen (choose the pen thickness depending upon what type knife you're sharpening, thin pen for 15-18 degrees, medium pen for 18-22 degrees, and a fat 'Sharpie' for your cleavers, [very thin pencil for a filet knife,]) and with some cloth tape, fasten it to the back of the blade near the spine. When you lay the knife on the sharpening abrasive (note that I didn't say 'stone...') the edge and the pen will hit at the same time, keeping the edge angle constant!

Next, forget about stones. They're expensive if you buy the good ones, and worthless if you buy the cheap ones. Instead, go to the automotive supply shop and get a few sheets of wet/dry sandpaper. They come in different grits so get 2 sheets of (aprox) 120, 360, 600, and one sheet of 800. If you want a shaving edge, get some 4,000 too, but don't use it for your kitchen knives!

Use some sort of completely flat backing board (or a sheet of glass) and with a glue stick, glue a sheet to the board. Begin with the smallest number grit. Now just scrub the knife back and forth. The pen will maintain the constant angle. Don't use a lot of pressure. About 30-40 strokes and you will be able to feel (with your fingernail dragged ACROSS the edge at 90 degrees to it, NOT ALONG THE EDGE!) a raised burr of metal on one side. Be sure that burr extends the length of the edge. Now turn the knife over to the other side and do the same thing, scrubbing off the burr. When you have the burr on that side, remove the old paper and go to the next finer grit of paper and repeat the process. When you reach the 800 grit, use less pressure (just the weight of the knife should be enough,) and stop just before you begin to raise the burr. You'll feel it. Then a few strokes alternating sides and your knife should be sharp. As the pen is guiding the angles for you, and the paper is large enough so you don't have to worry about missing it, and the fingers of your other hand are holding your beer, you are safe enough to not pay close attention. You can do all of this while watching the football match.

If all this takes you more than 10 minutes, you're doing something wrong. Re-read what I've written. It takes a lot longer to write this than to sharpen a kitchen knife. By the way, this method is know among knife-knuts as "Scary Sharp" but they (we?) will take the edge to between 12,000 - 60,000 grit using different lapping or polishing compounds. At 60,000 grit, you don't have to cut the veggies. You just point the knife at them and they fall apart from fear... (You can get the 60,000 grit compound at the jewelery making supply shop a block east of Chian Puak Gate facing the moat. It's a green colored 1/2 kilo Chromium Oxide bar.)

Now, if you really want a professional edge, as Bill suggests, you will want a secondary bevel. For that just use a thicker pen and only the 600-800 grit paper. There is even more controversy as to the need for this secondary bevel...

Edited January 2, 2009 by FolkGuitar

[zzdocxx]

That's interesting, where'd you learn that?

[FolkGuitar]

That's interesting, where'd you learn that?

If you are refering to the 'Scary Sharp' system, you can find plenty of references for it in all the knife forums, and especially in wood-working forums. Even Wikipedia. It's what most pro wood carvers use for their chisels. I've tried all the various sharpening devices as well as 'free hand' and found the 'Scary Sharp' method to be cheap, easy, and effective. Not necessarily 'better' than other methods, just cheap, easy, and effective. As for the pen trick, my grand father taught me that one when teaching me how to sharpen my cub scout knife! It works!

The most important part of getting a good edge is maintaining a consistent angle, and this is the part that throws of most new sharpeners and explains why so many different companies make clamping guide sharpening devices to hold the blade at a fixed angle to the abrasive. The exact degree number isn't nearly as important as long as you stay within the suggested ranges, and they are pretty logical. Low numbers for extra fine cutting, medium numbers for an edge that you apply more pressure to, and larger numbers for edges that get a lot of pressure such as cleavers, machetes, axes, etc.. The usual range is from 15° to 25°

The second most important aspect is blade geometry. If the original geometry is wrong (as if often found on inexpensive knives made from inferior steel,) it's difficult to get a good cutting edge. Re-profiling the edge will often turn a poorly cutting blade into a useful tool. To do that you MUST maintain a consistent angle when scrubbing against the abrasive, and use a lower number grit such as 80-120. After taking down the metal, then follow with the finer grits.

Next is the choice of edge grind for a specific use. Some are common, such as flat grind, saber grind, hollow grind, and the most ubiquitous double bevel grind. But there is also Scandi grind, convex grind, chisel grind, etc., etc., etc! for example, Japanese sushi knives are almost always chisel grind, i.e. beveled on one side only, and flat on the opposite. Swedish 'Mora' knives and the ethnic Sammi knives of Finland are Scandi ground. Your good quality straight razor is always hollow ground, and most folding knives, kitchen knives, and hunting knives are double bevel ground.

I've been making and collecting knives for 45 years, and still learn new and better ways to sharpen my tools. As Bill said in one of his posts, there are as many different ways to sharpen (and all of them 'the best way,') as there are people who sharpen. Personally, for kitchen use, I like to use the "Spyderco Sharpmaker." It's easy enough for a complete beginner, but does a great job on most kitchen tools. My wife can keep her knives in good shape, and there is little mess. A good mid-point device is made by Lansky, adjusts for different angles, is clamped and guided, and can be found in the Military Surplus stores on the NE corner of the moat and the sporting goods store in Airport Plaza. Easy to use, adjustable, but a bit messy. For getting exact angles when wanted, I use the "EdgePro" Apex. This is a fantastic device but at a lot higher cost and much more than most people need. I also use leather strops and various polishing compounds but that is really over-kill on anything other than a straight razor or wood-working tools. It's fun to be able to carve a strand of hair into a reproduction of the Eiffle Tower...

http://www.woodbutcher.net/scary.shtml

http://en.wikipedia.org/wiki/Scary_sharp

http://www.taunton.com/finewoodworking/pages/w00003.asp

Edited January 3, 2009 by FolkGuitar

[FolkGuitar]

That's interesting, where'd you learn that?

If you are refering to the 'Scary Sharp' system, you can find plenty of references for it in all the knife forums, and especially in wood-working forums. Even Wikipedia. It's what most pro wood carvers use for their chisels. I've tried all the various sharpening devices as well as 'free hand' and found the 'Scary Sharp' method to be cheap, easy, and effective. Not necessarily 'better' than other methods, just cheap, easy, and effective. As for the pen trick, my grand father taught me that one when teaching me how to sharpen my cub scout knife! It works!

The most important part of getting a good edge is maintaining a consistent angle, and this is the part that throws of most new sharpeners and explains why so many different companies make clamping guide sharpening devices to hold the blade at a fixed angle to the abrasive. The exact degree number isn't nearly as important as long as you stay within the suggested ranges, and they are pretty logical. Low numbers for extra fine cutting, medium numbers for an edge that you apply more pressure to, and larger numbers for edges that get a lot of pressure such as cleavers, machetes, axes, etc.. The usual range is from 15° to 25°

The second most important aspect is blade geometry. If the original geometry is wrong (as if often found on inexpensive knives made from inferior steel,) it's difficult to get a good cutting edge. Re-profiling the edge will often turn a poorly cutting blade into a useful tool. To do that you MUST maintain a consistent angle when scrubbing against the abrasive, and use a lower number grit such as 80-120. After taking down the metal, then follow with the finer grits.

Next is the choice of edge grind for a specific use. Some are common, such as flat grind, saber grind, hollow grind, and the most ubiquitous double bevel grind. But there is also Scandi grind, convex grind, chisel grind, etc., etc., etc! for example, Japanese sushi knives are almost always chisel grind, i.e. beveled on one side only, and flat on the opposite. Swedish 'Mora' knives and the ethnic Sammi knives of Finland are Scandi ground. Your good quality straight razor is always hollow ground, and most folding knives, kitchen knives, and hunting knives are double bevel ground.

I've been making and collecting knives for 45 years, and still learn new and better ways to sharpen my tools. As Bill said in one of his posts, there are as many different ways to sharpen (and all of them 'the best way,') as there are people who sharpen. Personally, for kitchen use, I like to use the "Spyderco Sharpmaker." It's easy enough for a complete beginner, but does a great job on most kitchen tools. My wife can keep her knives in good shape, and there is little mess. A good mid-point device is made by Lansky, adjusts for different angles, is clamped and guided, and can be found in the Military Surplus stores on the NE corner of the moat and the sporting goods store in Airport Plaza. Easy to use, adjustable, but a bit messy. For getting exact angles when wanted, I use the "EdgePro" Apex. This is a fantastic device but at a lot higher cost and much more than most people need. I also use leather strops and various polishing compounds but that is really over-kill on anything other than a straight razor or wood-working tools. It's fun to be able to carve a strand of hair into a reproduction of the Eiffle Tower...

http://www.woodbutcher.net/scary.shtml

http://en.wikipedia.org/wiki/Scary_sharp

http://www.taunton.com/finewoodworking/pages/w00003.asp

[zzdocxx]

Thanks FolkGuitar.

What an informative post. This is a little off the subject of Thailand per se, but where I live in San Diego, sharpening costs about $3 per knife. So I figured maybe I would be better off doing it myself, but had no idea there were so many different devices.

It ought to be worth the cost of a good sharpener if I sharpen my knives, and those of my mom, and then I'll start with my mom's friends' knives. (Divide $300 by $3, at 100 knives I'll break even, lol.)

Hey are those devices you recommended pretty easy to use?

I wonder how they do all those fancy edge grinds you mention?

Thanks again, I am going to take a look at those links.

Edited January 3, 2009 by zzdocxx

[JimShortz]

I know this is going to lead to some confusion, but I am going to actually answer the OP's question!

Go to Warorot market and find the dead escalator (has not worked for years). Go up the escalator and look to your right. You will see a shop that sells some cosmetic items, scissors, hair clippers, etc. Ask at this shop - success!

The guy who does the sharpening may or may not be at the shop; half of the time he's at a little booth around the back where he does the actual sharpening using some fairly heavy duty machinery. He will sharpen anything - hair clipper blades for me for instance. If you see him sharpening stuff he wears mad looking taped together glasses that make him look like a mad boffin serial killer. He may be a serial killer, I just don't know, but if he is a bet he uses a very sharp knife...

[FolkGuitar]

Thanks FolkGuitar.

What an informative post. This is a little off the subject of Thailand per se, but where I live in San Diego, sharpening costs about $3 per knife. So I figured maybe I would be better off doing it myself, but had no idea there were so many different devices.

There are dozens of different devices on the market today, some excellent, some very good, and many that aren't worth the money. Some sharpen, some hone, some just re-align the edge. If your knife is properly sharpened, and you don't try to cut rocks, you shouldn't need to sharpen it again for 5-6 months! 3-4 strokes with a metal or glass "butcher's steel" (I prefer borocillicate glass... Pyrex! Use the bottom of a loaf pan! Or use the unglazed bottom ridge of a ceramic bowl) before each use will keep that razor edge in good shape.

It ought to be worth the cost of a good sharpener if I sharpen my knives, and those of my mom, and then I'll start with my mom's friends' knives. (Divide $300 by $3, at 100 knives I'll break even, lol.)

You just might find that you have more business than you can handle... You wouldn't be the first person to start a sharpening service that way.

Hey are those devices you recommended pretty easy to use?

It varies from product to product. Sticking to the good ones, for someone only interested in sharpening home use knives (i.e. kitchen, pocket, or hunting,) 'Spyderco SharpMaker' (about $50 USD and found either on line or in better sporting goods stores,) is about the easiest to use and gives great results. It allows you two different edge angles, comes with two different grit stones (a third, a diamond stone is available and useful for REALLY screwed up edges!) and an instruction video, and will sharpen any blade from a tiny pen blade to a 14" French Chef's knife to a very useable working edge. It will sharpen scissors, shears, peelers... just about anything shorter than a sword. And all you have to do to use is is be able to slice straight down. That's it. Just keep the blade slicing straight down while drawing it across a stone that is held at the constant angle by the unit's base. Alternate 20-30 stokes per side and you're done! The stones are made of an alumina ceramic and are used dry.

Here is Youtube's demonstration;

http://jp.youtube.com/watch?v=6yVN9lLVPM4

http://jp.youtube.com/watch?v=48UZT7uskqg

The 'Lansky System' comes with a blade clamp, 3-4 stones of different grits, and a guide rod that holds the stone in the chosen angle. If I remember correctly, Lansky provides 4 different angles to chose from. Clamp the blade in the holder, start with a coarse grit stone with its rod in the chosen angle hole, and scrub away. Raise a burr, turn the clamp over and replace the stone and do the other side. Move to the next finer grit stone. Very easy and fast, but there is one drawback... It is NOT very easy to do larger (more than 8") blades. You have to reposition the clamp for that. Not difficult, but not as easy as the SharpMaker. It's a trade-off. More choice of angles, but more set-up needed.

YouTube says:

http://jp.youtube.com/watch?v=KW64B0MZVOE

DMT Company makes another, much cheaper (but just as effective as Lansky) clamp and guide system. GATCO is another guided clamp system that I prefer over Lansky as the stones are wider. All three make diamond stones for their systems which means that you use water instead of oil to remove metal filings. Much less mess.

To recap, the Spyderco Sharpmaker is easiest to use and works on small and large blades, the guided clamp systems are a bit more of a bother to set up but give you more control of angles as well as choice of angles, and my choice of clamps run to DMT or GATCO Once you get hooked by the knife-knut bug, you will want to purchase an "EdgePro" as it is the King of all hand operated sharpeners and will sharpen any angle, any length blade, and do so quickly and easily but costs three times as much as the sharpeners mentioned above.

http://jp.youtube.com/watch?v=0rYxHD3IzeY

All these systems will last a lifetime, especially if you chose one with either ceramic or diamond stones, and all will do a very effective job sharpening your tools. Or... you could just buy a stone and learn to free-hand sharpen, but good quality stones cost as much (or more!) as any of the systems above. I can free-hand sharpen but never bother with it. I prefer to use the Spyderco Sharpmaker for kitchen knives and either the DMT Aligner used with sandpaper instead of stones for the Scary Sharp style or the EdgePro Apex for the majority of my tools. Have fun with it!

[nokia]

I know this is going to lead to some confusion, but I am going to actually answer the OP's question!

Go to Warorot market and find the dead escalator (has not worked for years). Go up the escalator and look to your right. You will see a shop that sells some cosmetic items, scissors, hair clippers, etc. Ask at this shop - success!

The guy who does the sharpening may or may not be at the shop; half of the time he's at a little booth around the back where he does the actual sharpening using some fairly heavy duty machinery. He will sharpen anything - hair clipper blades for me for instance. If you see him sharpening stuff he wears mad looking taped together glasses that make him look like a mad boffin serial killer. He may be a serial killer, I just don't know, but if he is a bet he uses a very sharp knife...

Eureka! Finally the answer, although i had sharpened my knives temporarily using a stone.

How much does he charge ie clipper blades or a knife? Maybe i will ask him to sharpen a Medieval Halberd?? Just kidding...

Cheers!

halberd.bmp

[FolkGuitar]

I know this is going to lead to some confusion, but I am going to actually answer the OP's question!

Go to Warorot market and find the dead escalator (has not worked for years). Go up the escalator and look to your right. You will see a shop that sells some cosmetic items, scissors, hair clippers, etc. Ask at this shop - success!

The guy who does the sharpening may or may not be at the shop; half of the time he's at a little booth around the back where he does the actual sharpening using some fairly heavy duty machinery. He will sharpen anything - hair clipper blades for me for instance. If you see him sharpening stuff he wears mad looking taped together glasses that make him look like a mad boffin serial killer. He may be a serial killer, I just don't know, but if he is a bet he uses a very sharp knife...

Eureka! Finally the answer, although i had sharpened my knives temporarily using a stone.

How much does he charge ie clipper blades or a knife? Maybe i will ask him to sharpen a Medieval Halberd?? Just kidding...

Cheers!

Sharpen the halberd with a file.

[zzdocxx]

Thanks again FG.