Need Serious Help!

A

ALAMEDA

Joined
Nov 26, 2005
Messages
79
Yesterday I opened my brand new Spyderco Tri-Angle Sharpener.

I read the book. I watched the DVD. All beautifully explained.

I went to my knife drawer and took out a Sabitier Chef Au Ritz 8" carving knife (model 1100 or 4400 or something) which is at least 15 years old and has never ever once been sharpened. This is my first attempt at this, guys.

So I follow the instructions excatly as shown in the DVD and the book. All as shown.

After doing the sequense of steps: I take the blade and press it gently against my thumb nail. It bites into the nail and does not slide off it.

Next I take a ripe tomato and gently press the blade edge against the tomato. It slides off the skin. I press harder on the tomato. It won't cut it. I look at the edge of the blade and it "looks" sharp. I then but my finger on the edge. I slowly draw the blade across my bare finger. Nothing!

It would seem that I have not sharpened this knife in the least. After following the instructions to the letter.

What is going on, here? The guy in the video could sharpen (to scary sharp edges) practicually a ball bearing with this thing.

I know I am doing something major wrong!

And I know you guys know what that is.

Thanks.

Dan
 
The only thing you probably did wrong was your nail test. If the edge bites into your nail as it is supposed to, it will cut into your finger as well. At that point the edge is still rough but already well formed.

So my guess is that the knife that you tried to sharpen is so blunt that the 20 strokes on the sharpmaker are not anywhere close to being sufficent to reform the edge. Try the black marker trick. Paint the edge of the knife with a black marker and watch if you really abrade the paint directly at the edge.

Probably the best type of knife to use to get used to the Sharpmaker is a SAK, if you have one.
 
It's amazing what the a black magic marker will reveal... which is usually that you are not hitting the edge just yet...
 
The instructions for the Sharpmaker are good if your blade is set at the default angle (30 degrees or 40 degrees, inclusive). If it is your first time to sharpen the knife, it is likely that the angle is not set, so you will need to work it until it gets to the right angle. This will take far more than the 20 strokes recommended in the video.

Here are two good resources:
http://forums.egullet.org/index.php?showtopic=26036
Sharpening FAQ

Both recommend sharpening on just one side to raise a burr on one side, then alternating sides to raise a burr on the other side, then following the Sharpmaker instructions. I will add that if you raise too big a burr on the second try, it will be difficult to get rid of that burr on the smoother stones. I ended up having to go back to the medium/coarse stone in order to shave off the burr that I built on the medium stones, so I would try to remove the big burr on the medium/coarse stone before going to alternating strokes.
 
Also, make sure you alternate sides after each stroke to avoid burring one side or the other.
 
clmayfield i bet hit the nail on the head.. Hard to reprofile an old knife but just a minute on one kept sharp on the Sharpmaker.
 
Thanks for the suggestions.

I'll go back at it and try what you guys are saying.

What looks and sounds easy to do may not be the case at all. I could be doing this completely wrong, but I know I must be getting close.

If any of you were here you'd have this knife like a razor blade in minutes.

If there are other thoughts.....post 'em.

Dan
 
Hang in there buddy,

Check to see if it bites your nail from both sides. It could be that you have a burr on one side.

Also, as mentioned earlier, line the edge on both sides with magic marker and then give it a couple of swipes on both sides. If you have a magnifier you'll be able to see just where the stone is hitting the blade; the edge or the shoulder.
 
A tomato is one of the hardest things to cut, the finger check only fails on *really* blunt blades. I typically run edges down to 5-10% of optimal when doing edge retention comparisons and they still catch on finger nails.

Go back to the medium rods and instead of using the fingernail check on a piece of thin paper. You should see clear progress in the blade being able to slice the paper with less and less effort, eventually reaching the point when it just pushes right through it with no draw.

-Cliff
 
Cliff

A tomato is one of the hardest things to cut.
Click to expand...

That is an amazing fact to someone new to knives.

And yes, I may not be drawing this blade the correct way across the stones. Or I may just need to do this a couple of hunderd times on each side: not twenty!

I believe that once I get the hang of it, that owning knives will be a lot more enjoyable.

I've said from day one when I showed up here, that my firm belief about why 98% of the worlds population do not care one wit about knives is the fact that a knife (if one could speak to you) will tell you that as soon as you own it there is a never ending battle going on between you .....and it!

A knife is happiest (I believe) when dull and left alone. We people just won't give it "a rest".

Anyway, a little fun with this can't hurt either.

I'll eventually beat this Spyderco (and knives) at their own game!

Dan

How's it goin' tim?
 
Well, initial profile is really the key here. You started with a knife that very poor geometry because it has not been sharpened in 10 years. If you would start with Spyderco (even one that has been blunted quite a bit) you need probably less than 20 strokes per side. Same if you would sharpen a knife that is so thin that it has intrinsic good geometry like a SAK.

The way most people here keep their knives (in sharp and good condition), it need bare 5 strokes per side on the whites only to keep them sharp.

This is why there is so much talk about geometry and thinning out blades on this forum.
 
Over ripe plums are also very difficult to cut as well, unless a knife is really sharp it will just smash them because there is no support to the very tough skin. If you can slice very thin sections of rope tomatos and plums with little juice excaping them you have a very sharp knife, it is exceptionally sharp if you can do it with little draw. Fish which is not very fresh and a little soft is also very difficult to steak well.

The biggest problem with the Sharpmaker, or any specific angle rig, is that the edge on the knife isn't at the same angle as the one you are trying to apply, usually the factory bevels are more obtuse. This means you have to grind off a huge amount of steel before they match, with the Sharpmaker it can take hundreds of passes to even changes angle by a few degrees.

Of course you only have to do this once, each subsequent sharpening session is on the same angle so it should only take minutes to restore once you get it sharp. You can also lean a really coarse benchstone against
the Sharpmaker to speed up the process.

-Cliff
 
Al-

Sorry to hear about your problem. I have some questions.

Did you use the 40 degree setting? Did you start with the gray stone edge and get the knife edge very sharp before going to the gray flat where the edge should have gotten even sharper before you repeated the process with the white rods which should have gotten the edge almost razer sharp?

About the only time you need to use the 30 degree setting is when the knife has been sharpened so many times that you are not hitting the bottom edge on the 40 degree setting. A Sharpie Magic Marker will tell you this is happening as the black mark will not be removed at the 40 degree setting. What you are doing is putting a "double bevel grind" on the knife. I have a link below that shows this with pictures.

Lastly, did you rough up the rods with some kitchen cleanser or by rubbing them together. They come slick from the factory and need to be broken in a little. Don't force the blade into the rod, just keep gliding it across them and they will do their job and pull off enough steel for a very nice sharp edge. I have never been able to sharpen a knife the first time like the instructions say. It always seems to take longer and more strokes (never 20). A half hour is not unusual with a knife made from good tough steel that needs some reprofiling. If your old knife has a primary edge bevel of 50 degrees then even at the 40 degree setting you are not touching the edge bottom and will have some grinding off to get the edge angle properly established. I have an x-course DMT diamond whetstone for this which makes reprofiling go quickly as it is many time rougher than even the gray Sharpmaker rod and it hogs steel off well.

Like Cliff said once you get the knife properly profiled and sharpened the first time, then subsequent sharpenings are a breeze.

http://forums.egullet.com/index.php?showtopic=26036
 
DGG

Did you use the 40 degree setting? Did you start with the gray stone edge and get the knife edge very sharp before going to the gray flat where the edge should have gotten even sharper before you repeated the process with the white rods which should have gotten the edge almost razer sharp?
Click to expand...

Yes! I did

But you have to be aware of something here! I am not a "knife" person.

To explain this problem further:

The answers to date (while very helpful and to the point) would really only be fully understood by people (like you guys) who are close to the science of metal....angle/degree.....mathematics.....and other metarllurigal terms.

When you tell me, for instance "that I am not hitting the bottom edge on the 40 degree setting, and I am putting a double bevel grind on the knife", you are in a few words telling me.....that I am way over my head!

As a cop, when I pull people over in the dead of night, I know why I am doing what I am doing. Even if the vehicle operator does not.

Here at BF, I don't from Adam!

Dan
 
It's quite simple, Alameda; actually...

When you sharpen a knife, one of the ways to sharpen is a simple V grind (at any angle). The problem with a simple V grind is that it wears away quicker (especially when sharpened at extreme angles). This would be considered a single-bevel.

A double-bevel is when you sharpen the blade at 2 separate angles; on a Sharpmaker, you create the first bevel at 30 degrees inclusive (15 per side), but then you subtract 5 degrees further off the initial angle to create the second bevel (at the 40 degree, or 20 per side). Not only is this edge "stronger", but it will be easier to sharpen.

Eventually, though, you'll sharpen at 40 to the point where the blade edge becomes too thick. To thin it out, you can use the 30 degree stones to wear away the "shoulders" of the edge, and then create the second bevel.

What DGG is suggesting is that instead of working the knife at the 40 degree angle, you may need to start at the 30 degree angle instead to create the initial bevel. Once you've done this, switch to the 40 degree angle, and create the "true" edge. If you are using the 40 degree angle only, you may not be sharpening the "true" edge. Start on the 30 degree edge until the edge "feels" sharp, then switch to the 40 degree angle to double-bevel it.

Here is a crude picture (sorry) to illustrate the difference, the edge on the left is a single bevel and the edge on the right is a double-bevel (sharpened to 2 angles):

bevels.gif


If you'd like to see Sal do it again, check out on the DVD where he explains the use of the 30 degree angles.
 
DH Archer

All people (after seeing your graphic, and who are not knife people) would, without doubt, assume that every knife made, is a single bevel edge knife! I would stake my life on that statement!

Why is there such a knife as a double bevel edge blade, anyway?

You can see now that I am coming from a place of complete ignorance.

All I ever wanted to do was buy and own a good knife.

Nothing in life is that simple. A "good knife" is dying to revert itself into a dull knife.

One other thought. If, as I said earlier, that 98% of the people on the planet have no knowledge of sharpening knives, I can also add this:

The knife industry that manufactures these knives in all of their myriad forms does indeed love the fact that the general population has no inckling whatsoever, as to how to recreate that edge that came to them when they made the original purchase.

Think of it this way.

If every knife owner knew precisley how to recreate (over and over again) the scary sharp edge that they bought from the original purchase,the knife manufactures themselves would be on "the edge" of going the way of the dinosaurs.

Millions of people when confronted with a dull edge, just go out and buy a brand new edge. Their old knife stays in the kitchen draw.

And the Knife Industry is not staying awake at night hoping that people learn how to sharpen their product. Believe you, me.

KnifeKnuts at BF are the exception. They are the other 2% of the population.

I intend to get into that 2%

Dan
 
ALAMEDA said:
And the Knife Industry is not staying awake at night hoping that people learn how to sharpen their product. Believe you, me.
Click to expand...
With the exception of Spyderco! ;)

ALAMEDA said:
I intend to get into that 2%
Click to expand...
The Sharpmaker is definitely the easiest way to start. A lot of knifenuts graduate to the Edge Pro Apex after starting on the Sharpmaker, but I can guarantee that you'll get your knives SCREAMING sharp with the Sharpmaker! :cool:

Keep em sharp! :cool:
 
tim

Your link is the be all and end all of knife care and maintainence.

Even I could not come up with another question that is not addressed in this tutorial. And that is going some.

It is clear and easy to understand.

It's just a question of taking the time to get the knack of it.

Anyway.....I'm done (for now) on the sharpening aspect.

I'll come up with something else, though: it's only a matter of time.

Much appreciated,

Dan
 
Alameda, below is the body (and pics) of a post I made a while ago in this forum. It outlines two setups that may help if you need to remove a lot of metal to reprofile a blade, like with your really dull kitchen knife. With these setups, be sure to still use the magic marker to color the cutting edge.

You can ignore the math reference in the post. :)

------------------------

Get a coarse cheap sharpening stone (or a coarse expensive one ;) ) and a hunk of 2x4 cut at the appropriate angle. Use the 2x4 to hold the stone angled while you stroke the knife edge (blade held vertically like with a Spyderco Sharpmaker) along the stone. To polish the edge, you can get a ceramic stick sharpening rod from Smokey Mountain Knife Works for $0.99 each, then use the angled 2x4 to hold it at the same angle as the stone.

stone-jig.jpg


Or you can cut a notch in the board to trap the blade at approximately the angle you want and slide the stone over the edge pressed up against the stone. The angle is determined by the height and depth of the notch in the board and the spine-to-edge dimension of the blade. The 1:4 ratio shown equals about 14 degrees per side (28 degrees total edge angle). If you increase it to 1:6 you get about 10 degrees per side (20 degrees total edge angle). The math to figure this out is: Angle-per-side = arctan (Depth of notch / Length of notch).

stone-jig_notched-board.jpg
 
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