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View Full Version : Sharpening Issues...(if you are sensitive to bad sharpening, please avoid this)



ptolemy
08-11-2011, 06:08 AM
Hi everyone :)

I been working on my skills with waterstones and I think I am making some progress and my knives are pretty sharp but I have an issue.

It seems after the edge, other parts of the knife develop this muddy looks. Please don't mind the scratches, they were there ways before; just not the muddy look.

The best look near the tip

Here is my progression: 240grit (or 120 if needed) to grind away the bad and set the edge and then use 500 grit and 1000 grit to refine it and smooth it down

Then I use green brick to sharpen/prepolish and finish with 6000 for mirror like edge.

I am thinking that my angle maybe too low but if I raise it, in past, the blade would catch on the stone (even in slurry/water).

I would really like to learn how to do it myself on waterstones :)

Thanks for the advice :)

http://i125.photobucket.com/albums/p63/ptolemy2k6/knife/IMG_1936.jpg

http://i125.photobucket.com/albums/p63/ptolemy2k6/knife/IMG_19361.jpg

Benuser
08-11-2011, 08:08 AM
Which angles did you use?

tk59
08-11-2011, 10:57 AM
You clearly have a bevel. It is a compound bevel but a bevel nonetheless. I would take a magic marker and draw lines from edge to spine along the entire length of your knife. Make one normal pass on the stone. I wouldn't bother with the sub-500 grit stones, either. Use a finishing stone. See what you're hitting. I think you're just wildly inconsistent. I don't understand how you get a bevel at all, lol. Anyway, keep on doing the marker thing until you're only hitting the edge. It will take a very, very long time to refinish the side of the blade on stones. I would recommend you use a block of wood with some spongy material on it and sandpaper on top of that. Rub it in one direction until the finish is even-looking. Go up in grit until you're satisfied with the size of the scratches. Do you flatten your stones, btw?

ajhuff
08-11-2011, 01:58 PM
Hey Ptolemy, my advise from one rookie to another, though caveat emptor, this advise may be frowned upon by the experts.

Stack 4 pennies on the near end of your stone. Set the edge of the spine on top of the pennies. Slowly sharpen per usual trying to just graze the top penny with the edge of the spine. Do this until you get a burr then flip and do the other side. This will help you be more consistent with hitting your angle and help you develop muscle memory. Works for me at least.

As to your scratches on the rest of the knife, you'll have to do as tk59 said and sand them out.


-AJ

tk59
08-11-2011, 04:00 PM
...Stack 4 pennies on the near end of your stone. Set the edge of the spine on top of the pennies. Slowly sharpen per usual trying to just graze the top penny with the edge of the spine. Do this until you get a burr then flip and do the other side. This will help you be more consistent with hitting your angle and help you develop muscle memory. Works for me at least... Another variation is to sharpen sectionally with the spine toward you and switch hands so you can always keep an eye on the height of your spine to keep your angle constant.

ajhuff
08-11-2011, 04:25 PM
What I do with the pennies. :)

-AJ

chazmtb
08-11-2011, 04:28 PM
I have told my family members to use the plastic slide from a report cover to slide in the spine of the knife.
Only thing you have to worry is to make sure that it is lifted enough away from the stone for the desired bevel angle.
One like this.
http://static.www.odcdn.com/pictures/us/od/sk/lg/678708_sk_lg.jpg

It is the same/similar concept to having a clip on guide that is sold.

Eamon Burke
08-11-2011, 11:39 PM
Not sure I understand what the problem is...

goodchef1
08-11-2011, 11:50 PM
Not sure I understand what the problem is...

I was trying to figure it out also, I will go out on a limb and say that he does not understand why the blade gets cloudy during sharpening, and if it is because of his sharpening angle. Or, what causes this cloudy finish on his blade when sharpening.

If it is not either of these, I'm still in the dark. :(

jmforge
08-12-2011, 12:22 AM
What is the blade made from?

ptolemy
08-12-2011, 01:36 AM
I was trying to figure it out also, I will go out on a limb and say that he does not understand why the blade gets cloudy during sharpening, and if it is because of his sharpening angle. Or, what causes this cloudy finish on his blade when sharpening.

If it is not either of these, I'm still in the dark. :(

I had 2 questions: If that cloudy should be there or if I am doing it wrong. My guess was that I am doing it wrong. Personally, the cloudy thing doesn't bother me but if I am to invest in more expensive knives, obviously if I decide to sell them down the line, i'd like them to be in pristine condition.


What is the blade made from?

I believe this is a solingen steel with moly/v/gr additives


You clearly have a bevel. It is a compound bevel but a bevel nonetheless. I would take a magic marker and draw lines from edge to spine along the entire length of your knife. Make one normal pass on the stone. I wouldn't bother with the sub-500 grit stones, either. Use a finishing stone. See what you're hitting. I think you're just wildly inconsistent. I don't understand how you get a bevel at all, lol. Anyway, keep on doing the marker thing until you're only hitting the edge. It will take a very, very long time to refinish the side of the blade on stones. I would recommend you use a block of wood with some spongy material on it and sandpaper on top of that. Rub it in one direction until the finish is even-looking. Go up in grit until you're satisfied with the size of the scratches. Do you flatten your stones, btw?

This was a factory edge badly sharpened before, so I had to reset the edge, so I used the low grit stone. Yes, I flatted the stones too. I will likely not going to waste my time with polishing it as it has no effect on how the knife works.

My main concern is cloudiness comes from bad technique or normal :)

Thanks:)

tk59
08-12-2011, 02:09 AM
...My main concern is cloudiness comes from bad technique or normal...

If you are only sharpening the edge, you might get a tiny cloudy area right at the shoulder of the bevel. This area is so thin that no one except the most anal-retentive people even notice it. All of my knives look close to new unless I've modified them somehow.

Keith Neal
08-12-2011, 07:11 AM
As a beginner learning to do this, I may be able to help. It looks like the angle of the blade on the stone is varying, giving the rounded look to the sharpened edge. Maintaining a constant angle is critical, so I wanted a way to achive that. I got out my compass and drew the angle I wanted on a piece of paper, then cut an old credit card to that angle. I don't use it to guide the sharpening, but to check the angle and make sure it is not changing. At first, I had to check it every stroke, going very slowly. Now I can use the stone for a while without checking every stroke, but I still check periodically, particularly if I have gotten distracted. Hope this helps.

(As with most things in life, accuracy is the key, not speed. Speed will come of its own accord with practice. If you try to go fast, you will never get good.)



1397


Incidentally, Dave Martell's DVD on knife sharpening is the best investment a beginner can make.

Keith

jmforge
08-12-2011, 02:47 PM
Just put it on the 3200 rpm 1 hp buffer with a sisal wheel......that will clean up those scratches fast!!!!:scared4::biggrin:

bieniek
08-12-2011, 04:09 PM
I had 2 questions: If that cloudy should be there or if I am doing it wrong.

My main concern is cloudiness comes from bad technique or normal :)


Yes, you are doing wrong.
That cloudiness is coming from laying knife flat on the stone/laying knife almost flat on the stone/pressing too high onto side of the blade which basically makes youre moves even more wobbly.
It is effect of fine stone contacting metal on the move.

Are your fingertips bloody after sharpening? Were before? If never, that means you are pressing onto too high of a spot at your blades side, not as close to edge as possible.
How is your pressure?

Lefty
08-12-2011, 04:58 PM
To make it simple:
If you're sharpening the edge of your knife (which you are), there is no reason for the face of the blade to contact the stone. So, in answer to your question, the muddy look and the other stray scratches are huge indicators you're doing something wrong. As TK said, the only "muddy" part should be about 0.0001" directly on top of the bevel. We are, after all, human.
Work on hitting ONLY your intended bevel angle.
One of my old teachers at Fire School told us, "It's the opposite of sex. In this, you get good, then you get fast".

Eamon Burke
08-12-2011, 06:14 PM
If you want to clean up the face of the blade, I'd suggest using 3M wet/dry sandpaper, in varying grits, with a little mineral oil. You can clean it right up(the logo will be gone, though).

The face of the blade doesn't ever need to be on the stone. Just the edge bevels.