I hate the final sharpening - Is it just me?

Using a nice crisp belt for sharpening really is far more efficient.

I actually use a new belt and sharpen on the platen, this gives me a nice flat grind at the angle I want.

I know many just guesstimate the angle but I like to know the exact angle, just makes the process easier for me.
 
Using a nice crisp belt for sharpening really is far more efficient.

I actually use a new belt and sharpen on the platen, this gives me a nice flat grind at the angle I want.

I know many just guesstimate the angle but I like to know the exact angle, just makes the process easier for me.

How do you know the exact angle?
 
That's a good technique. How ever it's done, working with matching angles, throughout the sharpening process, should be, the goal.

Slack belt created edges are sharp, but almost impossible to recreate without sharpening on the same machine. If a convex edge is sharpened on a stone or diamond plate. the edge is being reground, flattened. Why not just make it flat in the beginning? Most people don't have a slack belt grinder.
I'm saying, as a rule of thumb in knife making, flat edges are the most serviceable in the life of the knife.


Make them sharp, Fred
 
"Why not use ceramic?"
Because ceramic doesn't come in finer than 220 grit. Same with Zirconia, it doesn't come higher than 120 grit.

A45 Trizact belt worked great, but I stopped using them because they don't seem worth the extra cost, and you can't run them wet.
I used the 372 micron belts in 40 micron size, but the edges are like razor blades.

I normally use the yellow 3M AO belts I get from Pop's ( I'll have to look at what number they are). They have a lubricant in the matrix that helps them run cooler.
 
That's a good technique. How ever it's done, working with matching angles, throughout the sharpening process, should be, the goal.

Slack belt created edges are sharp, but almost impossible to recreate without sharpening on the same machine. If a convex edge is sharpened on a stone or diamond plate. the edge is being reground, flattened. Why not just make it flat in the beginning? Most people don't have a slack belt grinder.
I'm saying, as a rule of thumb in knife making, flat edges are the most serviceable in the life of the knife.
That's what I love about knifemaking... I agree with many of the points but come to a different conclusion, at the end of the day. I jump back and forth between sharpening on belts, oil stones, wheels, diamond, water stones, ceramic rods, carbide jigs and lapping sheets on granite. Sure, I have my favorites, but they ALL work. I totally respect but get a kick out of some of the gadgets/jigs folks use to get the "perfect edge"... some of them remind me of the Rube Goldberg machines.

I was a knife enthusiast and user loooong before I was a maker and never once fretted about the original angle of the edge. Chris Reeve, was one of the first high-end knives I owned and remember dreading the day I had to touch it up. The edge it came with was the sharpest I had ever encountered and it simply showed me that edges could get sharper than I thought. Maybe all this newfangled, stay-shiny steel that requires abrasives forged from the heart of a dying star to sharpen has changed the game.

Learning how to get a knife sharp on a multitude of $#!tty equipment has taught me more about edges than any single miracle method could.

Oh. yeah.... and the final sharpening is the best part... aside from having the payment clear and the delivery confirmation notice.

Rick
 
"Why not use ceramic?"
Because ceramic doesn't come in finer than 220 grit. Same with Zirconia, it doesn't come higher than 120 grit.

A45 Trizact belt worked great, but I stopped using them because they don't seem worth the extra cost, and you can't run them wet.
I used the 372 micron belts in 40 micron size, but the edges are like razor blades.

I normally use the yellow 3M AO belts I get from Pop's ( I'll have to look at what number they are). They have a lubricant in the matrix that helps them run cooler.
@stacy ,ceramic belts are self sharpening , right ? Correctly used and handled /right speed and pressure most important / ceramic grain break , right ? So what is going on when on 40 grit grain tip break in use / I forget grain size / getting smaller and smaller? And after some period of grinding steel , maker say ........that's it this belt is worn and no more good for grinding ? But if he slow down the speed on that belt and use for some other task / like for first sharpening / that WORN belt .............. :) They don t worn...they change grit size . I have two worn ceramic belts in maybe +400 grit size . After grinding blade on 40 grit ceramic I use that belts for light pass on low speed and I get amazing finish.If belt is not properly used diamond dresser will help to make them usable again ........
 
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Sharp knife, chest level with edge facing you on moving belt. It does not get more dangerous on belt grinder then that.

There is a reason they no longer allow knife makers to sharpen and grind on the top of a belt like that on Forged in Fire :)
If I remember correctly, it was because they were standing next to the grinder and leaning over the belt. Almost hugging it under their right armpit(they may have even been standing on a box). If you can cut/snap a belt while grinding at 30% speed, with the edge facing away from the rotation, I'll give you .... a new belt. You can argue a safety issues with just about any piece of equipment in your shop. I saw nothing overly dangerous about the video, aside from not wearing safety glasses.

I consider myself a stickler for shop safety and cringed more at Lon's video, that you linked to.(and not just because its a video showing the best way to get a razor sharp edge on a knife... lol ... that never gets old)
 
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That's what I love about knifemaking... I agree with many of the points but come to a different conclusion, at the end of the day. I jump back and forth between sharpening on belts, oil stones, wheels, diamond, water stones, ceramic rods, carbide jigs and lapping sheets on granite. Sure, I have my favorites, but they ALL work. I totally respect but get a kick out of some of the gadgets/jigs folks use to get the "perfect edge"... some of them remind me of the Rube Goldberg machines.

I was a knife enthusiast and user loooong before I was a maker and never once fretted about the original angle of the edge. Chris Reeve, was one of the first high-end knives I owned and remember dreading the day I had to touch it up. The edge it came with was the sharpest I had ever encountered and it simply showed me that edges could get sharper than I thought. Maybe all this newfangled, stay-shiny steel that requires abrasives forged from the heart of a dying star to sharpen has changed the game.

Learning how to get a knife sharp on a multitude of $#!tty equipment has taught me more about edges than any single miracle method could.

Oh. yeah.... and the final sharpening is the best part... aside from having the payment clear and the delivery confirmation notice.

Rick

If I remember correctly, it was because they were standing next to the grinder and leaning over the belt. Almost hugging it under their right armpit(they may have even been standing on a box). If you can cut/snap a belt while grinding at 30% speed, with the edge facing away from the rotation, I'll give you .... a new belt. You can argue a safety issues with just about any piece of equipment in your shop. I saw nothing overly dangerous about the video, aside from not wearing safety glasses.

I consider myself a stickler for shop safety and cringed more at Lon's video, that you linked to.(and not just because its a video showing the best way to get a razor sharp edge on a knife... lol ... that never gets old)[/QUOTE
It's hard to have wisdom & commonsense and not show it. :D
 
@stacy ,ceramic belts are self sharpening , right ? Correctly used and handled /right speed and pressure most important / ceramic grain break , right ? So what is going on when on 40 grit grain tip break in use / I forget grain size / getting smaller and smaller? And after some period of grinding steel , maker say ........that's it this belt is worn and no more good for grinding ? But if he slow down the speed on that belt and use for some other task / like for first sharpening / that WORN belt .............. :) They don t worn...they change grit size . I have two worn ceramic belts in maybe +400 grit size . After grinding blade on 40 grit ceramic I use that belts for light pass on low speed and I get amazing finish. If belt is not properly used diamond dresser will help to make them usable again ........ natlek

When normal grains fracture they get coarser, not finer. The tips break off exposing a wider surface.

Structured abrasives, like the Cubitron have square grains that do shear off exposing a new square surface with sharp edges and corners. They grind the same from new to old. The issue is having enough speed and pressure to shear the grains.

Ceramic belts have an abrasive of tiny ceramic grains ( micro-crystalline) fused into aluminum oxide grains. Each individual grit is composed of many tiny grains. This makes the grit very strong … and hard … so the belts take more pressure and speed to work. For tasks like sharpening, that is the opposite of what you want to do. As the belts wear, they get coarser. If used at lower speeds, or with light pressure, the aluminum oxides fuse and "smear" together to make the belt seem worn out. This is why many newer makers with low power grinders don't like them. Put that belt on a 2HP or larger grinder and run it at high speed while bearing down on it with an old carborundum grinding wheel or a diamond dresser for a minute and it will cut like brand belt. Ceramic belts HAVE to be run fast and used hard to work. If that isn't possible with a persons grinder, get Zirconium belts.
 
@stacy ,ceramic belts are self sharpening , right ? Correctly used and handled /right speed and pressure most important / ceramic grain break , right ? So what is going on when on 40 grit grain tip break in use / I forget grain size / getting smaller and smaller? And after some period of grinding steel , maker say ........that's it this belt is worn and no more good for grinding ? But if he slow down the speed on that belt and use for some other task / like for first sharpening / that WORN belt .............. :) They don t worn...they change grit size . I have two worn ceramic belts in maybe +400 grit size . After grinding blade on 40 grit ceramic I use that belts for light pass on low speed and I get amazing finish. If belt is not properly used diamond dresser will help to make them usable again ........ natlek

When normal grains fracture they get coarser, not finer. The tips break off exposing a wider surface.

Structured abrasives, like the Cubitron have square grains that do shear off exposing a new square surface with sharp edges and corners. They grind the same from new to old. The issue is having enough speed and pressure to shear the grains.

Ceramic belts have an abrasive of tiny ceramic grains ( micro-crystalline) fused into aluminum oxide grains. Each individual grit is composed of many tiny grains. This makes the grit very strong … and hard … so the belts take more pressure and speed to work. For tasks like sharpening, that is the opposite of what you want to do. As the belts wear, they get coarser. If used at lower speeds, or with light pressure, the aluminum oxides fuse and "smear" together to make the belt seem worn out. This is why many newer makers with low power grinders don't like them. Put that belt on a 2HP or larger grinder and run it at high speed while bearing down on it with an old carborundum grinding wheel or a diamond dresser for a minute and it will cut like brand belt. Ceramic belts HAVE to be run fast and used hard to work. If that isn't possible with a persons grinder, get Zirconium belts.
This was my inspiration for moving to a 3 hp drive motor and a 6 inch drive wheel. The combination changes, the way a person grinds and how much can be accomplished in a given amount of time. If one is serious about grinding blades, the change will pay for itself in a short amount of time.
 
@stacy natlek

When normal grains fracture they get coarser, not finer. The tips break off exposing a wider surface.

Structured abrasives, like the Cubitron have square grains that do shear off exposing a new square surface with sharp edges and corners. They grind the same from new to old. The issue is having enough speed and pressure to shear the grains.

Ceramic belts have an abrasive of tiny ceramic grains ( micro-crystalline) fused into aluminum oxide grains. Each individual grit is composed of many tiny grains. This makes the grit very strong … and hard … so the belts take more pressure and speed to work. For tasks like sharpening, that is the opposite of what you want to do. As the belts wear, they get coarser. If used at lower speeds, or with light pressure, the aluminum oxides fuse and "smear" together to make the belt seem worn out. This is why many newer makers with low power grinders don't like them. Put that belt on a 2HP or larger grinder and run it at high speed while bearing down on it with an old carborundum grinding wheel or a diamond dresser for a minute and it will cut like brand belt. Ceramic belts HAVE to be run fast and used hard to work. If that isn't possible with a persons grinder, get Zirconium belts.
Then how you will explain this ? With new ceramic belt I get big scratches , with long time used ceramic belt / high speed no more good , to much heat / I get many time finer finish ? I use so far only Klingspor ceramic belts .....
Here how they break/worn................from Klingspor site

ceramic ................

xWAepQw.jpg


zirconia.......................

C0Zrsr8.jpg


Aluminium oxide...........

nPpd8zE.jpg


Silicon carbide...............

8pre4nh.jpg
 
If you can cut/snap a belt while grinding at 30% speed, with the edge facing away from the rotation, I'll give you .... a new belt.

Very generous, but no one was talking about all of that.

When a belt does breaks, all by itself, it could easily slap that blade into your chest sharpening like that.

In my 55 years, 40 as a craftsman I have never had a stitch and aim to keep it that way due to common sense.

I remember as a Boy Scout the first lesson they teach you about using a knife is to not cut toward yourself.

If a maker has a VFD they could spend a few extra buck and put a reverse switch on it and sharpen all day with the edge facing away from him
 
If used at lower speeds, or with light pressure, the aluminum oxides fuse and "smear" together to make the belt seem worn out. This is why many newer makers with low power grinders don't like them. Put that belt on a 2HP or larger grinder and run it at high speed while bearing down on it with an old carborundum grinding wheel or a diamond dresser for a minute and it will cut like brand belt. Ceramic belts HAVE to be run fast and used hard to work. If that isn't possible with a persons grinder, get Zirconium belts.

So what about bevel grinding? When making my bevels I only run the vfd at 45hz. Any faster and I can't do a single pass without burning the hell out of my fingers.
Should I switch to zirc belts?
 
So what about bevel grinding? When making my bevels I only run the vfd at 45hz. Any faster and I can't do a single pass without burning the hell out of my fingers.
Should I switch to zirc belts?
If you can only get 1 pass then you probably want to try a new technique. Also running that slow you are probably glazing the belt and will have extra heat. Use belt for profiles and lean on them and the should do great.
 
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