Cheap vs expensive diamond stones

[MattFromCanada]

The yellow Swix diamond stone on the left is faced with adhesive backed resin bonded diamond sheet from the Swiss company KGS Diamond https://www.kgsdiamond.com/ the pattern used on the one in the photo is Swiflex, another popular pattern is Telum. Most if not all of the aluminum backed diamond stones sold by the major wax companies are made by Skiman in Italy http://www.skiman.it/edge-tuning/diamond.aspx

The smaller ski tool manufacturers also use KGS diamond sheet, usually the diamond sheets on these stones extend to the edge of the aluminum backing and you can get replacement sheets https://www.sidecut.com/category/ST.html.

The Moonflex stones also use resin bonded sheet http://www.sorma.net/interna.php?op=131

DMT stones are made from diamond coated sheet metal, all the diamond grains are on the surface so they wear out quicker than the resin bonded stones, which have diamond grains distributed throughout the resin.

This was amazingly informative. Thank you!


On a slightly related note, what does everyone do to keep their stones clean? I've been using denatured alcohol and a toothbrush but that seems to take years to clean all the debris and gunk out of them, even with liberal lubricators while using.

 

[Jacques]

I don't always agree with Jaques but when I do........
Honing without a lubricant to flush away the swarf and cool the asparities that contact the edge and do the cutting will ruin a stone very quickly.
This was beaten into me by an old German toolmaker who was a true artist in metal.
You shouldn't use much pressure on a hone either.
Honing fluid for skis cannot contain oil so I use a mix of 90% water, 10% denatured alcohol with a few drops of detergent.
Freshly honed surfaces will corrode quickly at the edge so wax 'em up after honing.

Ha ha! I'll agree^. Swarf! Keep them clean, don't over pressure.

 

[Sibhusky]

This was amazingly informative. Thank you!


On a slightly related note, what does everyone do to keep their stones clean? I've been using denatured alcohol and a toothbrush but that seems to take years to clean all the debris and gunk out of them, even with liberal lubricators while using.

I occasionally use the wax remover I got for my skis, works like a charm. Almost never use it for the skis, just do hot scrapes.

 

[Jacques]

"Diamond stones are ok for doing touch up work but if you have a damaged edge from running across a rock and it leaves a section where it's nasty, don't try and clean it up with a diamond stone, regardless of the grit. I always use a file to cut that nasty stuff off and depending on how bad it is, I'll often use a panzer file to cut that nasty rash off so I don't dull or damage my good files."

I don't think so.
You should always remove burrs with a coarse diamond stone before filing.
The deformed metal in the burrs is harder than the steel in the file and dulls the teeth.
A few passes with a coarse diamond before filing...always!

I will say

This was amazingly informative. Thank you!


On a slightly related note, what does everyone do to keep their stones clean? I've been using denatured alcohol and a toothbrush but that seems to take years to clean all the debris and gunk out of them, even with liberal lubricators while using.

Like said above by Sibhusky. Some wax remover works good, yet consider how it got so clogged up in the first place.
Still wax on edges etc. Use a fiber pad to clean first. Still this can be brushed out in solution as you go along.
Plastic in the stone. One may need to pull back the sidewall deeper. Use a sidewall planer.
Plastic in stone from base edge. Just brush it out in solution.
Just in case......one doesn't know......brushing out stones is usually done with tooth brush size brushes of brass, or steel. If steel, use stainless steel.

 

[Dakine]

"DMT stones are made from diamond coated sheet metal, all the diamond grains are on the surface so they wear out quicker than the resin bonded stones, which have diamond grains distributed throughout the resin."

That is not sheet metal.
The best way to glue diamond grains together is to use a molten metal alloy that will wet the diamond crystals when molten and be strong when solid.
Turns out the metal that works best is a nickel alloy.
The diamond grit ends up in a puck of nickel superalloy.
Resin bonded diamond stones last longer because the resin will wear away exposing fresh diamond faces.
Cast metal ones are flatter and stronger.
They all work but I use Moonflex for its open pattern and moderate price.
I think you pay a big premium for anything that says "Ski" on it while diamond stones are a commodity in the metal shaping industry.
DMT = Die, Mold & Tool, their real market.

 

[mdf]

DMT knife sharpening stones: $17
https://www.sharpeningsupplies.com/DMT-Aligner-Replacement-Stones-P126C168.aspx

DMT Ski tuning stones: $28 on sale for $24
http://www.artechski.com/dmt-diamond-whetstone-tool/

 

[Zrxman01]

I have no strong opinion here.

 

[Jacques]

I have no strong opinion here.

View attachment 38417

Very nice! Mucho gusto!

 

[Beerman]

"Diamond stones are ok for doing touch up work but if you have a damaged edge from running across a rock and it leaves a section where it's nasty, don't try and clean it up with a diamond stone, regardless of the grit. I always use a file to cut that nasty stuff off and depending on how bad it is, I'll often use a panzer file to cut that nasty rash off so I don't dull or damage my good files."

I don't think so.
You should always remove burrs with a coarse diamond stone before filing.
The deformed metal in the burrs is harder than the steel in the file and dulls the teeth.
A few passes with a coarse diamond before filing...always!

I don't get your logic. If a file is ok to work a ski edge, before the edge is damaged, what happens during the damage period to make it no longer ok for a file to remove material, in this case a burr??
Hardening of Metals can only occur under very high temperatures and then fast cooling.

Sorry, we are digressing from the OP.

 

[Franzz]

Those credit size cards are my choice for years, $40.00 cdn at MEC for the kit

 

[Wade]

Hardening of Metals can only occur under very high temperatures and then fast cooling.

That’s not true.

I think the hardening that is being referred to here is work hardening. From Wikipedia:

• In work hardening (also referred to as strain hardening or cold working) the material is strained past its yield point. Ductile metal becomes harder and stronger as it physically deformed. The plastic straining generate new dislocations. As the dislocation density increases, further dislocation movement becomes more difficult since they hinder each other, which means the material hardness increases.

 

[Dakine]

@Beerman.....both work hardening which involves stacking up crystal dislocations and phase transition hardening occur when an edge hits a rock.
You have to think on the atomic scale to realize that when metal is ripped apart from an impact it gets very hot indeed on a very small scale.
It is also quenched quickly which is what you need to form martensite crystals that are a much harder form of iron than the mostly ferrite material used in edges.
This all happens in a few milliseconds leaving a very hard burr that will cut into file teeth and dull them.

 

[Beerman]

That’s not true.

I think the hardening that is being referred to here is work hardening. From Wikipedia:

• In work hardening (also referred to as strain hardening or cold working) the material is strained past its yield point. Ductile metal becomes harder and stronger as it physically deformed. The plastic straining generate new dislocations. As the dislocation density increases, further dislocation movement becomes more difficult since they hinder each other, which means the material hardness increases.

I agree with your statement about work hardening, but i don't agree that that is what is happening. As work hardening means 'the material is deformed many times and with each deformation, the material becomes harder, tougher etc'. With the impact of rock on edge it is only a single deformation/impact etc.

@Beerman.....both work hardening which involves stacking up crystal dislocations and phase transition hardening occur when an edge hits a rock.
You have to think on the atomic scale to realize that when metal is ripped apart from an impact it gets very hot indeed on a very small scale.
It is also quenched quickly which is what you need to form martensite crystals that are a much harder form of iron than the mostly ferrite material used in edges.
This all happens in a few milliseconds leaving a very hard burr that will cut into file teeth and dull them.

I'd have to agree more along the lines of this comment. But dont agree that a file can't handle this condition. Files will dull from normal duty anyway, so a slightly harder section should still be handled ok with a file IMO, although couple more strokes may be required.

Thanks for the info guys, a different angle is always good.

 

[CalG]

Diamond abrasives are sold in the industrial world in two types.
Bonded and plated
Bonded diamond abrasives are characterized by volume,matrix hardness, and diamond concentration, those and grit size .

Plated abrasives are but a single thickness applied to a supporting substrate, All or nothing. grit size and plating integrity is all you get in return for your "Euro".

I'm sure "marketing" has an influence in price and value. The crafty marketeers will not divulge the technical details of their products.

Such is the condition of the typical consumer. You get what you pay for ... at times.

 

[ottothecow]

I have no strong opinion here.

View attachment 38417

I recognize those stones. 95% sure they are made by Boride abrasives. The gray ones look like CS-HD stones, the white are probably AM-K.

Don't know what sun valley charges, but you can get them cheap in lots of sizes from tooling companies.

https://www.moldshoptools.com/catalog/list.php?category_id=74

 

[Jacques]

I recognize those stones. 95% sure they are made by Boride abrasives. The gray ones look like CS-HD stones, the white are probably AM-K.

Don't know what sun valley charges, but you can get them cheap in lots of sizes from tooling companies.

https://www.moldshoptools.com/catalog/list.php?category_id=74

Or you can go right to the source here. https://www.borideabrasives.com/PublicStore/Default.aspx

 

[DavidSkis]

I recognize those stones. 95% sure they are made by Boride abrasives. The gray ones look like CS-HD stones, the white are probably AM-K.

Don't know what sun valley charges, but you can get them cheap in lots of sizes from tooling companies.

https://www.moldshoptools.com/catalog/list.php?category_id=74

Are those stones "good" for tuning skis? If so, which ones?

 

[ottothecow]

Or you can go right to the source here. https://www.borideabrasives.com/PublicStore/Default.aspx

Only if you want to buy in bulk though!

Are those stones "good" for tuning skis? If so, which ones?

No idea... Just getting back into the ski tuning game, which is how I stumbled onto this thread.

I use them for sharpening knives, and the CS-HD stones in particular are fantastic for sharpening hard steel. Maybe overkill for ski edges though (and unlike files/diamond plates, you must re-flatten stones after moderate use).

 

[PTskier]

An abrasive stone is also suitable for removing the work hardened burr caused by hitting a rock. Either stone or diamond, then file, then burnish.

Good definition of work hardening:
"Strain hardening (also called work-hardening or cold-working) is the process of making a metal harder and stronger through plastic deformation. When a metal is plastically deformed, dislocations move and additional dislocations are generated. The more dislocations within a material, the more they will interact and become pinned or tangled. This will result in a decrease in the mobility of the dislocations and a strengthening of the material. This type of strengthening is commonly called cold-working. It is called cold-working because the plastic deformation must occur at a temperature low enough that atoms cannot rearrange themselves. When a metal is worked at higher temperatures (hot-working) the dislocations can rearrange and little strengthening is achieved."
https://www.nde-ed.org/EducationResources/CommunityCollege/Materials/Structure/strengthening.php

I've seen work hardening with just a single deformation--I've bent steel tubing and other parts; they bend easily and break when I try to re-work them. Or maybe the loss of ductility isn't exactly work hardening. In any case, I usually wish I hadn't bent them in the first place.

 

[hotwinter74]

stones are made from diamond coated sheet metal, all the

DMT knife sharpening stones: $17
https://www.sharpeningsupplies.com/DMT-Aligner-Replacement-Stones-P126C168.aspx

DMT Ski tuning stones: $28 on sale for $24
http://www.artechski.com/dmt-diamond-whetstone-tool/

WS4X stones and A4X stones have different price level even though they look same to me.
Are they same stones but just different product code?
Or something different?

When I asked it to DMT, CS replied to me
"The A4X model is for use with the Aligner kit we sell. The WS4XX is meant for removing burrs caused by snow, rocks, and ice. If you are looking for ski maintenance, I would recommend the WS4XX.

Here is the rest of our line of ski and snow edge care https://www.dmtonlinestore.com/collections/ski-and-snowboard-edge-care "

Well, I need extra-coarse to extra-fine stones but there is no green stone (extra-fine) in the WS4XX group.