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Purpose of Ceramic/Gummy Stones

Cork7 Belly Flop

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What are the main differences between ceramic/gummy stones for
deburring/derusting/polishing edges? What do they do that diamond
stones don't other than increase the longevity of said diamonds?

Specifically, I see various sites advertise coarse ceramics and soft
gummies for the same deburring/derusting jobs: why use one over the
other?

Likewise, fine ceramics/hard gummies are advertised for final
polishing after diamond stones. I always thought fine grit diamonds
were the end point for polishing.

I just assumed gummies were for detuning.
 

Atomicman

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There is always a little burr on the edge point (not a hanging burr) after sharpening whether file/diamond/ceramic/surgical stone. Once you knock off the hanging burr, to get the smoothest cleanest edge, an xtra-hard blue gummi down the edge point at a 45 degree angle with absolutely NO pressure leaves an ultra smooth edge point! Feel the edge point before the gummi and after. You'll feel the difference.
 
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draco

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I go from diamond stones to fine ceramic. It allegedly hardens the edge. I also lightly waft a hard gummi along the actual point of the edge to knock off any remaining burrs. Why? Because @Atomicman told me to. :ogbiggrin:
Why would it harden the edge?

Tthere is always a little burr on the edge point after sharpening whether file diamond/ceramic/surgical stone. Once you knock off the hanging burr, to get the smoothest cleanest edge, an xtra-hard blue gummi down the edge point at a 45 degree angle with absolutely NO pressure leaves and ultra smooth edge point! feel the edge point before the gummi and after. You'll feel the difference.
Is it something like the process from this Swix tuning video? You do one pass with the diamond stone, then one pass with the ceramic stone to bring back the burr on the correct side?
The guy from the video says, that the ceramic stone has no abrasive qualities. Are every ceramic stones like that?
 

Atomicman

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Why would it harden the edge?


Is it something like the process from this Swix tuning video? You do one pass with the diamond stone, then one pass with the ceramic stone to bring back the burr on the correct side?
The guy from the video says, that the ceramic stone has no abrasive qualities. Are every ceramic stones like that?

I think he is just talking about sharpening and honing the side edge? There is no correct side for a burr. If you hand sharpening or polish the side edge you are going to end up with a hanging burr that goes down into the snow straight down off the side edge and this will cause total havoc with how your skis perform and it won't break off when skiing. If you use a stone on the base edge yes it will create a burr going the other direction, straight out from the base edge, that will break off when skiing and isn't as detrimental to ski performance but you shouldn't be fooling with your base edge once set and polished.

You must knock off a hanging burr caused by hand sharping and diamond stoning. In this case. you place your ski edge up in a vise, base away from you and put your stone flat against the base edge sticking up about 1/3 of the way above the side edge, using your thumb as a guide on the sidewall. Run the stone up and down the base edge a couple of times keeping the stone in contact with the metal base edge. I use a Surgical stone or true hardstone to knock off the hanging burr.

After this step, then you use the X-tra hard blue gummi as I have described above.

By the way Razor Tune does not create a hanging burr, but to be safe, I still do the step here to ensure it and use the blue gummi after!
 

draco

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There is no correct side for a burr
What I meant was, when you sharpen one side of the edge, the bur forms/curls on the other side. Then with pass with the stone you flip it back again on the "correct" side that you are sharpening, so that on the next pass with the file/diamond stone, that bur will be broken

What is the difference between all these ceramic stones? Hardness level? Or in the case of the arkansas stones - coarseness?
https://www.tesmasport.com/snoli-arkansas-true-hard-stone
xap13_arkansas_rgb.jpg


https://www.tesmasport.com/ski-tuning-waxes/edge-tuning/stones-and-gummi/snoli-arkansas-hard-stone
fab13_arkansas_hard_rgb.jpg


https://www.tesmasport.com/ski-tuni...nd-gummi/sks-ceramic-stone-for-fine-polishing

sks_ceramic_stone_3252.jpg


And lastly - is this good for extra hard blue gummi?
https://www.tesmasport.com/ski-tuning-waxes/edge-tuning/stones-and-gummi/snoli-multi-gum
204-m-snoli-rubber.jpg
 

oldschoolskier

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There is always a little burr on the edge point (not a hanging burr) after sharpening whether file/diamond/ceramic/surgical stone. Once you knock off the hanging burr, to get the smoothest cleanest edge, an xtra-hard blue gummi down the edge point at a 45 degree angle with absolutely NO pressure leaves an ultra smooth edge point! Feel the edge point before the gummi and after. You'll feel the difference.
Extremely rarely will I counter what @Atomicman writes.

Proper methodology in using the stone/diamond/ceramics leaves no burrs so gummies are not needed. Until you master this, using a gummi as @Atomicman suggests can help. Personally, I have never used a gummi stone, but then again I was taught correctly.
 

Atomicman

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Extremely rarely will I counter what @Atomicman writes.

Proper methodology in using the stone/diamond/ceramics leaves no burrs so gummies are not needed. Until you master this, using a gummi as @Atomicman suggests can help. Personally, I have never used a gummi stone, but then again I was taught correctly.
What I meant was, when you sharpen one side of the edge, the bur forms/curls on the other side. Then with pass with the stone you flip it back again on the "correct" side that you are sharpening, so that on the next pass with the file/diamond stone, that bur will be broken

What is the difference between all these ceramic stones? Hardness level? Or in the case of the arkansas stones - coarseness?
https://www.tesmasport.com/snoli-arkansas-true-hard-stone
xap13_arkansas_rgb.jpg


https://www.tesmasport.com/ski-tuning-waxes/edge-tuning/stones-and-gummi/snoli-arkansas-hard-stone
fab13_arkansas_hard_rgb.jpg


https://www.tesmasport.com/ski-tuni...nd-gummi/sks-ceramic-stone-for-fine-polishing

sks_ceramic_stone_3252.jpg


And lastly - is this good for extra hard blue gummi?
https://www.tesmasport.com/ski-tuning-waxes/edge-tuning/stones-and-gummi/snoli-multi-gum
204-m-snoli-rubber.jpg
Yep!
 

oldschoolskier

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What does this mean?....I have no clue.
1672690853329.jpeg
When you cut into the edge any material is pulled onto the edge so the burr is prevented, if you draw off of, you tend to drag material off the edge in doing so you are creating the burr. Pulling parallel to tends to behave similar to a draw off.

This is why some of the rotary sharpeners depending how set leave no burr and achieve a sharper edge. The rotation is into the edge, if it is reversed a burr is formed.

This is something taught when learning to sharpen tools. Those that don't learn it, learn how to remove burrs. Believe it or not it, it is a difficult concept to understand because a small portion of the edge acts like plastic and moves, by the direction we control the movement.
 

Atomicman

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I am having a hard time understanding how you can polish the side edge, say even with a diamond with the motion you've shown. Are side edge guides even designed to do this?

Sharpening tools and a side edge of a ski are akin to each other? Maybe I am slow, but this makes no sense to me on the side edge of a ski.
 

mdf

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1) There is a similar concept in sharpening knives, except the goal is opposite. I find a controlled burr too fussy to create (and too fragile in use) so I settle for a non-burred edge by cutting in (moving knife on stone as if I was whittling it). I can get a very sharp knife that way, even though a true expert could get it even sharper by doing it "right".

To be honest, if I'm sharpening knives I'm often just trying to get an AirBnB knife to minimally useful.

2) I do not see how you can cut in on a ski edge with an edge guide. Seems contrary to the whole operating principle of a guide.

3) Based on theoretical considerations, I believe a diamond stone can create a burr. But I've never had one big enough to notice. On the other hand, files often make burrs big enough to cause problems.
 

James

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This is what he’s talking about:

14CAF3C0-5059-4D46-ABEA-1DDC9226C93D.jpeg

Cuts into the edge.
You can have binding/brake clearance issues with the end of the file.
 

Atomicman

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This is what he’s talking about:

View attachment 187676
Cuts into the edge.
You can have binding/brake clearance issues with the end of the file.
James, this is not what OS was talking about this is just standard fare side edge work. Did you hear the video guy say he is using the 400 grit paper to knock off the burr on the bottom side of the edge created from filing & sharpening. @1:56 ???
 

Atomicman

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He’s talking about a file I presume.
Makes no difference what you use if you are sharpening or polishing of course a file is going to be worse. I don't see how you can file or polish a ski side edge and NOT create a hanging burr on the ski side edge IMHO.
 
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Atomicman

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2) I do not see how you can cut in on a ski edge with an edge guide. Seems contrary to the whole operating principle of a guide.

3) Based on theoretical considerations, I believe a diamond stone can create a burr. But I've never had one big enough to notice. On the other hand, files often make burrs big enough to cause problems.
100% :golfclap:
 

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