Benchstones: Necessity for dressing / roughening the surface?

[Roy C. Deps]

Hello,
a couple of month ago I bought a set of benchstones. Until today I am very happy with that stones. They work great on my knives and gardening tools, whatever the steel is. They are easy to clean. But there is one point that unsettles me. I have read more than once that the fine and ultrafine stone will get finer and smoother until they are so smooth that they won't cut / work. Meaning one has to dress or roughen the surface to expose fresh "grit".
Is that true?
I know that some guys lap their stones with SiC powder or diamond abrasives. But I have neither one nor the other. And I don't want to buy those stuff.

As I clean the benchstones with a liquid scouring agent (a household cleanser, similar to Barkeepers Friend?), I ask myself if that is not enough for roughening the stone's surface periodically.

I would appreciate any helpful comments. Hopefully my request is comprehensible, as I am not fluent in English.
Thanks.

[sal]

Hi Roy,

Welcome to our forum.

Over a long period of time, it is possible that the medium grit stone and even possibly the fine stone might become finer, but that's an awful lot of use. The ultra fine is a fine that has been surface ground with diamonds. I don't know of a way to make them coarser.

The medium grit is friable and if it wears enough to crack the surface, it will become coarser. The medium grit triangles will wear enough on the corners to crack the surface and then they cut faster. In fact I usually recommend that one should crack the surface of one corner on each triangle by rubbing two together,

sal

[blues]

An option made by a German company and perhaps available in your area are the rubberized Sandflex Sanding Blocks. They have many household uses and can be used on the ceramic hones if you need to lightly abrade the surface.

I've had them around the home and shop for years, though I generally use a rubber artist eraser or Barkeepers friend for lighter cleanings.



https://www.amazon.com/Sandflex-Sanding ... B000GACU1Q

[JacksonKnives]

I have read more than once that the fine and ultrafine stone will get finer and smoother until they are so smooth that they won't cut / work. Meaning one has to dress or roughen the surface to expose fresh "grit".
Is that true?
I know that some guys lap their stones with SiC powder or diamond abrasives. But I have neither one nor the other. And I don't want to buy those stuff.

As I clean the benchstones with a liquid scouring agent (a household cleanser, similar to Bar Keepers Friend?), I ask myself if that is not enough for roughening the stone's surface periodically.

In my experience, scouring the stones when they become glazed is all that's necessary.

I've read about people lapping the UF stone to make it more perfectly perfectly flat for sharpening straight razors with very straight edges and precise technique. (My stone is already flat enough for the sharpening I do so I haven't tried it.)

A change to the surface could change the scratch pattern it leaves on the edge. So theoretically you could change a UF back into a F, though (as Sal suggests) lapping with a common abrasive/plate wouldn't likely achieve that. (Maybe etching or blasting to increase porosity could do it?)

Just thinking out loud, I'd bet if you wanted faster cutting you could also use the "medium" ceramic stones with a slurry of natural water stone/grinding powder/diamond powder floating on top. It'd change the characteristics of how the stone grinds, for sure. Probably wouldn't be worth the mess though.

[Roy C. Deps]

Thanks guys.
I don't want to change the surface. The stones work great as they are and if they stay so, wonderful. For me there is no need to make them finer or coarser.

Some guys made it sound as if there is a need to lap the stones quite often.
Now I feel soothed and can enjoy sharpening without having to think about lapping or dressing or whatever. Just sharpening and cleaning.

[S-3 ranch]

Ran across this on breaking in stones, maybe it will help
https://scienceofsharp.com/2015/09/10/d ... -break-in/
https://scienceofsharp.com/2014/05/28/d ... reak-down/

[Michael Janich]

Dear Roy C. Deps:

Welcome to the Spyderco Forum.

Stay safe,

Mike

[yablanowitz]

Thanks guys.
I don't want to change the surface. The stones work great as they are and if they stay so, wonderful. For me there is no need to make them finer or coarser.

Some guys made it sound as if there is a need to lap the stones quite often.
Now I feel soothed and can enjoy sharpening without having to think about lapping or dressing or whatever. Just sharpening and cleaning.

Some kinds of stones wear and dish out pretty quickly, and require lapping to bring them back to flat for best results. I have old carborundum stones that are worn so badly that they are unusable. Spyderco ceramic benchstones don't wear quickly, so they don't require flattening often.

[awa54]

With natural stones, water stones and general purpose commercial oil stones, flattening is definitely something that needs to be done on a regular basis, since the grit particles break away with use (by design, or nature) to expose fresh abrasive, but true ceramic stones don't shed grit particles (or binder) anywhere near as fast.

With finer grit ceramic stones, it's mostly removing embedded metal particles from the surface that needs to be done regularly to preserve their cutting ability. This is what you're doing when you scrub them with comet/barkeepers friend/scotchbrite pad/rust eraser.

I suppose that you could eventually wear a saddle into a ceramic hone, but it would take years of every day use... if you ever did do that, the solution would be to flatten it on a coarse diamond plate, or with coarse SiC grit on a glass plate, then lap it to the correct grade by using grit that's similar to the stones own abrasive size/equivalent. I can tell you from experience, that this takes a *long* time to do, even with diamond abrasives.

[Roy C. Deps]

Thanks for all the replies and your help.
I am not very concerned about wearing the stones because of their hardness and because I don't use them daily.
It was more about glazing or burnishing (is there a difference?) the surface (and therefore the need to roughen the surface from time to time), as some guys in knife forums say. But that seems to be an unnecessary concern.

[JD Spydo]

Thanks guys.
I don't want to change the surface. The stones work great as they are and if they stay so, wonderful. For me there is no need to make them finer or coarser.

Some guys made it sound as if there is a need to lap the stones quite often.
Now I feel soothed and can enjoy sharpening without having to think about lapping or dressing or whatever. Just sharpening and cleaning.

Some kinds of stones wear and dish out pretty quickly, and require lapping to bring them back to flat for best results. I have old carborundum stones that are worn so badly that they are unusable. Spyderco ceramic benchstones don't wear quickly, so they don't require flattening often.

I agree with what you just said for the most part>> however I've had to replace at least 6 of the MEDIUM grit stones on my 204 Sharpmaker kits ( I have 2 of them)>> and this is over many years of usage. And I've had to replace one of the medium grit 302 Spyderco Benchstones because it ended up dishing out somewhat in over 8 years of pretty hard usage. But I've never yet had to replace any of my "FINE" or "ULTRA-FINE" Spyderco stones either in the 204 Sharpmaker kits or the 302 Benchstones. Now I do take that back in one instance because I did have one of the FINE stones on one of my 204 Sharpmaker kits end up chipping so bad on the corners that I did replace one of those. But it was the only one of those grits that I ever had a problem with.

But with all the usage I've gotten from my "MEDIUM" Spyderco stones I really can't complain a great deal because I do use all of those stones a lot in a year's time.