Why am I so rubbish at sharpening a knife?

[Stringmaker]

Let me begin by saying that I have read (and copied) the sticky tutorial, and have all the right grades of abrasives, along with a good quality strop and honing paste.

I also know the basic principle of working on one edge, then the other, then alternative edges.

I attempted to sharpen a blunt vegetable knife this week and the stages went like this:

200 grade: seemed to be creating a sharp edge

400 grade: seemed to becoming less sharp

600 grade: definitely less sharp

Strop: Blunt!

Thinking it through, it seems like I am rounding off the initial 200 edge with my subsequent ham fistedness, which clearly suggests poor technique. I am holding the same edge angle for each step; is that where I go wrong?

This is something I want to be at least competent at, so all help very gratefully recieved.

Thanks in advance

 

[Leonidas]

Best way is to pop along to a knife maker and ask them to show you...
Where in the UK are you?

Tom

 

[Nonsuch]

Beware - many kitchen knives are made of very soft steel that will not hold an edge. I have exactly the same experience with various kitchen knives whereas I can get my bushcraft knives will all types of grind (scandi, flat with secondary bevel, convex) to shavers without too much difficulty. I can in fact get a reasonable edge on a kitchen knife using a Lansky, but this disappears very quickly. Also, the micro-bevel on kitchen knives has usually been messed up and needs re-setting, but this will only work if the steel is up to it in the first place. I have a so-called Sabatier knife which is a total turkey. On the other hand I have a Global Japanese knife which takes a lot of work to sharpen but holds a beast of an edge...:yikes:

The edge you are feeling with the 200 is just ragged micro-serrations, which disappear as you progress.

Try sharpening an 01 tool steel scandi grind. If that doesn't get sharp then you do have a problem. Otherwise blame the knife!

 

[Stringmaker]

Thanks for the comments.

My problem is that I don't even get to the stage where there IS an edge, let alone one that gets lost.

What about the number of repetitions per abrasive per edge? The sticky tutorial advises increasing the reps as you go finer?

 

[Ogri the trog]

It is very difficult to predict how many passes per grade of abrasive, as if you haven't brought the faces together to form an angle, there will always be a blunt edge in-between them.

Can I take it that you've used such tricks as marker pen on the edge to see where material is being removed from; angling the blade in bright light to see if any reflection comes from blunt sections of blade and so on.

Are you using stones or wet/dry paper - which might be rucking up in front of the edge as you push.

Ogri the trog

 

[Stringmaker]

It is very difficult to predict how many passes per grade of abrasive, as if you haven't brought the faces together to form an angle, there will always be a blunt edge in-between them.

Can I take it that you've used such tricks as marker pen on the edge to see where material is being removed from; angling the blade in bright light to see if any reflection comes from blunt sections of blade and so on.

Are you using stones or wet/dry paper - which might be rucking up in front of the edge as you push.

Ogri the trog

I am using stones; albeit one of the rectangular diamond stone blocks with four grades. It is flat and was used by someone else to demonstrate on a penknife so I know that tool works as it should; it's me that's the problem.

I hadn't used the marker pen trick but I shall when I try again later, thanks for the reminder.

I think you may have nailed the basic problem, along with Nonsuch and his comment about the 200 grade serrations I was feeling. I don't think I brought the faces together at all, merely produced two separate bevels. The knife in question had a distinct secondary bevel, but I'll have a go at a simple scandi grind and see how I get on.

Thanks chaps

 

[geordienemisis]

I myself was US at sharpening then downloaded a tutorial off Greenpete, and just took my time. I also made a strop from some old leather from a settee, contact glued it to a piece of wood 10x4 inches and use that as a final strop. paper cutting sharpness every time,its best never to rush and don't use to much pressure. I am no way an expert but practice makes perfect. some of the guys on here are just superb at knife making and if you follow their advice you can't go wrong.

 

[The Lord Poncho]

I am far from an accomplished sharpener myself, but i do recall someone mentioning that stropping (or actually, to that matter, using the mouse mat method) with too much force can cause the leather to rise up behind the edge as you drag it, blunting it.

 

[Stringmaker]

It is a bit of a black art isn't it?

It is also the perfect winter "garage" project for me to practice. Last winter I kept filling the place with smoke from bow drill practice!

 

[luckylee]

the best thing to do is, start to sharpen the one side, and keep feeling the other side untill you get a burr, now think about the amount of strokes you want to start with, say 20, then start on the side that you have created a burr on, and remove that burr, by sharpning that side for 20 strokes, then when you look on the other side you shoud have a burr, the same as you got when you first started sharpning the first side, now start sharpning that side with the next grit down from what you started sharpning with, and then look on the other side and you will have a burr, but a finer one, another 20 strokes, and turn over, and take that burr of, and keep going down your grits untill tou get to 1200, and pushing the bur from one side to the other, the burr will gradually get smaller the less grit size you use, when you get to 1200 grit and you have done your 20 strokes each side, then start sharpning ones side once, and then the other side once for 15, 10, 5, then a few times each say 2 one side at a time, then take to the strop and carfully strop each side 20 times each, and the a few singles, ie one side, the flip over then the other side flip over, if you have done all this, you should have a shaving sharp knife, i hope all this has made sense, you need to keep pushing that bur from one side to another untill the bur has gone, and strop.
take care.
lee.

 

[Ogri the trog]

Those burrs are the key, but also a stumbling block.....

It is possible to create two separate burrs, one on one surface and another on the other surface;- you can see a burr when you flip the knife over and look in bright light - but if the faces have not met at an edge - all of a sudden the blade goes blunt. Blacksmiths call it a "fish-mouth" where one surface moves out over the edge that it covers - if the same happens on both sides of a piece - voila, no edge.

I've been looking for an image but it remains elusive.

Ogri the trog

 

[luckylee]

Those burrs are the key, but also a stumbling block.....

It is possible to create two separate burrs, one on one surface and another on the other surface;- you can see a burr when you flip the knife over and look in bright light - but if the faces have not met at an edge - all of a sudden the blade goes blunt. Blacksmiths call it a "fish-mouth" where one surface moves out over the edge that it covers - if the same happens on both sides of a piece - voila, no edge.

I've been looking for an image but it remains elusive.

Ogri the trog

interesting bud, i have never had this happen, would love to see what you mean.

 

[Stringmaker]

Is it possible to be a bit too keen and press too hard on the stone?

I am taking a "firm slice" each stroke, would a lighter action be better for 20 reps?

I have a good idea now of how to try again so this will be my last dumb question on the subject!

 

[AuldJum]

Is it possible to be a bit too keen and press too hard on the stone?

I am taking a "firm slice" each stroke, would a lighter action be better for 20 reps?

I have a good idea now of how to try again so this will be my last dumb question on the subject!

The weight of the blade should be the weight on the stone.

Keep practing though, i struggled at first and made a mess of a few knifes before i could sharpen effectively.

When my grandad taught me he didn't become annoyed that i was blunting his knives but encouraged me to keep going.

If you have a good knife, a good stone and sound understanding of how to sharpen then only practice will help.

Good luck, you'll get there.

 

[Stringmaker]

The weight of the blade should be the weight on the stone.

Keep practing though, i struggled at first and made a mess of a few knifes before i could sharpen effectively.

When my grandad taught me he didn't become annoyed that i was blunting his knives but encouraged me to keep going.

If you have a good knife, a good stone and sound understanding of how to sharpen then only practice will help.

Good luck, you'll get there.

Ah, sounds like I was pressing too hard then.

Thanks for the encouragement!

 

[Samon]

have you got a picture of the knife? a good one so we can see the type of grind/edge. What's the blade material?

It could be a case of crap knife.. or over enthusiastic sharpening

either way we will help you get a knife sharp! hehe

 

[jollo74]

the best thing to do is, start to sharpen the one side, and keep feeling the other side untill you get a burr, now think about the amount of strokes you want to start with, say 20, then start on the side that you have created a burr on, and remove that burr, by sharpning that side for 20 strokes, then when you look on the other side you shoud have a burr, the same as you got when you first started sharpning the first side, now start sharpning that side with the next grit down from what you started sharpning with, and then look on the other side and you will have a burr, but a finer one, another 20 strokes, and turn over, and take that burr of, and keep going down your grits untill tou get to 1200, and pushing the bur from one side to the other, the burr will gradually get smaller the less grit size you use, when you get to 1200 grit and you have done your 20 strokes each side, then start sharpning ones side once, and then the other side once for 15, 10, 5, then a few times each say 2 one side at a time, then take to the strop and carfully strop each side 20 times each, and the a few singles, ie one side, the flip over then the other side flip over, if you have done all this, you should have a shaving sharp knife, i hope all this has made sense, you need to keep pushing that bur from one side to another untill the bur has gone, and strop.
take care.
lee.

Quoted for emphasis: this is it ! In my experience, at least 90% of the time someone has a problem with getting a nice sharp is that the bevels don't meet. There is no shortcut to a sharp knife, you have to sharpen "all the way through" until a burr is formed. I wouldn't worry too much about this "fishmouth" Ogri mentioned - I've never seen it happen and I'd guess a knife must be REALLY REALLY blunt for 2 burrs to form...

After you have the burr, which should be clearly visible on a 200 grit diamond plate, you have to gradually remove it. One trick helping to remove the burr is to pull the knife LIGHTLY through the "face side" (right expression ) of a piece of hardwood.

And yes, stropping with too much pressure acrually bluntens a knife (been there ...).

Cheers
Jörg

 

[Stringmaker]

Thanks for the new comments folks.

I don't have a picture of the blade but it is not a Scandi grind; it has a definite secondary bevel. As suggested, I think my problem was twofold:

1. The bevels I was creating didn't meet

2. I was definitely grinding too hard with all the grades, especially the stropping.

I had another go on the same veggie knife, going 200, 300, 400, 600 with much less pressure and this time I could feel an edge coming on. I'm still not happy with the results so will keep practising until one of two things happens:

1. I get the thing sharp

2. I'm left with a handle and no blade!

As I go along, I'll try and get a good close up of the blade so you can see the lash up I'm making of things. If you followed my pump drill story then you can expect plenty of ups and downs along the way!

 

[nickliv]

Have you tried a spyderco sharpmaker? I got one a month or so back, and it's incredible.

 

[Highbinder]

Don't despair, I know how you feel! I've had a hell of a time trying to get a consistent sharpening. Theres something about the stropping motion I just can't articulate. I can see improvement (slowly) but it's made me prefer steels that are easier to put an edge to - I can strop my opinel or spyderco to a razor, but the CPM3V on my BRK is just a pain in the behind.