Glazed stone

wardcleaver

wardcleaver

Joined
Apr 17, 2017
Messages
290
I've got a spyderco Medium grit pocket stone that wont take a cleaning with Bar Keepers friend anymore, its smooth and dosnt seem to cut very well.

Would dressing it on a DMT course or extra course bench stone work to rough it up again.
Definitely dont want to do anything that would damage the DMT.

Anyone have any thoughts one this?
 
Might go with the XC diamond. I've lapped 3 small ceramic hones (1 Lansky, both sides of a Spyderco DoubleStuff hone) using either/both of DMT C & F hones. They did a decent job in getting the ceramics flat and cutting well, although a coarser diamond would have been a better choice for me, to keep the finished result closer in grit to the original. With either the Coarse or Fine diamond, the effective finish on the ceramics ended up much finer than original, emulating something like a UF Spyderco.

If you keep pressure LIGHT, and do the lapping immersed in water or oil (keeps swarf from clogging the diamond), that'll go a long way toward protecting the life of your diamond hones. They can handle the job; just be patient and don't overgrind on them.

I've also used an inexpensive Harbor Freight diamond hone in an XC or XXC grit to resurface a Fallkniven DC4's ceramic, very similar to Spyderco's medium grit. I think that diamond hone was ~ 180-grit, as rated on it's packaging. That also worked well, and I think even better than the DMTs in finer grit. Even that cheap HF diamond hone held up well, in that job, again used with a light touch in sort of a figure-8 scrubbing pattern.
 
Last edited:
Glad to hear the stone can be reconditioned.
David Martin said:
Do you have a SiC stone? DM
Click to expand...
I assume I would want to use as course of a grit as possible?

Obsessed - I like the Harbor Freight diamond hone idea too. Might be the cheapest way to go.

Mr.Wizard said:
Loose SiC grit works, and it leaves a fine matte finish that I think you will like.
Click to expand...
How do you use the loose grit?

Thanks guys.
 
wardcleaver said:
Glad to hear the stone can be reconditioned.

I assume I would want to use as course of a grit as possible?

Obsessed - I like the Harbor Freight diamond hone idea too. Might be the cheapest way to go.

(...)
Click to expand...

The one thing to watch, if trying the HF hone, is making sure it's FLAT. The one I used was part of a 3-hone set, each thin metal plate mounted on a thin & warped plastic backing. Some time back, I remounted each of those to my own stiffer, flatter backing of 1/2" plywood, which made them more user-friendly, and simply more useful in general. HF also sells a 4-sided diamond block, which (hopefully) would be flatter and not so in need of some sort of backing reinforcement.

Assuming the backing is flat, the HF hones are essentially expendable, based on price. I paid $10 for the 3-hone set. So these are the types of jobs I'd reserve for such hones, and save my DMTs for sharpening knives. ;)

In terms of coarseness, I think anything up to maybe XXC would do OK. Kind of have to try one out & see. But if using anything finer than XC, like Coarse or Fine (325/600 DMT), it's very likely you'll end up with something emulating a UF or finer ceramic. If that's what you're aiming for, no problem. Just be aware of it.
 
When I did my Spyderco ceramic 2"X8" stone, just one side was out of level and I wanted that side level and finer than the fine side.
I used a coarse dmt and fine. Which worked great. That one side is X fine now and works very good for razors. Just that one ultra fine stone
is 80$ to your door. So, I wore down my used coarse stone to not have to purchase a 80$ stone. DM
 
I hope I can resist using my DMT XC lightly just to see what happens.
It's a 30 mile drive to Harbor Freight.

...orrr just buy replacement stone for $19
 
It depends on how much your stone if out of level. That will determine how much rubbing you'll need to do. Using Your
X- coarse lightly will work but it will wear the diamond stone. Use water. Your call. Ha, ha. Be glad it's only 30 miles to Harbor Freight. It's 150 miles for me, each way. DM
 
The stone is still flat, I just want to rough up the surface a bit so it cuts better.
If I use dia., it will be a cheap HF stone, or buy a new ceramic.

I guess 30 mi. doesn't sound so far after all...:D
 
wardcleaver said:
The stone is still flat, I just want to rough up the surface a bit so it cuts better.
If I use dia., it will be a cheap HF stone, or buy a new ceramic.
I guess 30 mi. doesn't sound so far after all...:D
Click to expand...
Hi,
to resurface a stone (rough it up)
You can also use use sic sandpaper if you already got some,
ideally slightly coarser than grit rating of stone,
short lubricated rub, no more than 10 seconds
for spyderco medium P1500 sandpaper or coarser

wardcleaver said:
How do you use the loose grit?
Click to expand...
Sprinkle a little pinch of loose grit on a floor/wall tile ($1),
sprinkle some water too,
spend 10-20 seconds rubbing the stone on the grit with figure 8 movements,
until the grit breaks down and stops sounding crunchy
its very short
You can see youtube.com/user/stefanwolf88/search?query=spyderco
both flatten (longer rub) and condition (short rub) every kind of sharpening stone
 
While sandpaper may work it is very slow and the grit breaks down pretty quickly and then you're just polishing your stone smoother.. The bad part about sandpaper is all of that glue that is used to secure the grit to the backing is being ground into the pores of your stones and clogs it up. I've tried zircon sandpaper and it works - but is still VERY slow. With very coarse grades of paper you may cut scratches and grooves into the surface of the stone. Using 60 to 90 grit silicon carbide powder works ten times as fast and leaves the finish like it was when it was new because the grit is rolling over and over exposing new cutting surfaces until it breaks down. With sandpaper the grit is stationary and dulls quickly. I flattened a fine Norton India and two Arkansas stones last weekend with 80 grit silicon carbide powder on a flat paving stone. You can also use a tile or thick glass. Those stones were all dished but they are perfectly flat now and cut like new. And it only took 15 minutes to do them all. If you use a diamond stone you will pretty much trash it and it will take forever.
 
Last edited:
On sintered ceramics like the Spyderco hones, I've also found sandpaper (SiC wet/dry) to be nearly ineffective; feels like rubbing smooth glass against smooth glass, with little or no swarf generated in the process. Even more so, if the grit of the sandpaper isn't very, very coarse starting out. SiC is brittle, so it breaks down very fast against other hard materials. Being that the abrasive layer of sandpaper is very shallow, it can't be 'refreshed' frequently with coarser grit as it works, as needs to be done when using loose SiC grit for a similar purpose.

With other stones, it can work OK. But sintered ceramic is much harder and denser in the way the grit is bound together, being essentially fused under extreme heat and the grit itself becomes part of the binder. So, sandpaper won't be very effective on it.
 
Last edited:
Obsessed with Edges said:
On sintered ceramics like the Spyderco hones, I've also found sandpaper (SiC wet/dry) to be nearly ineffective; feels like rubbing smooth glass against smooth glass, with little or no swarf generated in the process...
Click to expand...
Hi,
Why would you expect to generate a lot of swarf when conditioning an already flat stone with fresh abrasive, the last seconds of light lapping (10 max)?

The goal is not to break down the sandpaper grit,
merely to roughen up the surface of spyderco hone,
it doesn't take much.
 
If it's just a few seconds of contact to condition an already flattened surface it might be fine, just make sure you use SiC wet/dry and not AlO. SiC loose grit will last a little longer but it also breaks down very rapidly when using it to flatten a Spyderco ceramic. That's why it's nice that you can instantly refresh the grit by adding some more as O.W.E. noted above. Can't do that with wet/dry unless you change the sheet. 2-body abrasion (wet/dry for instance) also doesn't give you the same surface texture as 3-body abrasion (loose grit) for the same grit size. You need to use considerably coarser wet/dry than you would if using loose grit.
 
I revisited this a little bit yesterday, experimenting with my Fallkniven DC4's ceramic side, which had a few glazed spots on it from use. Used a piece of fresh ~320-grit SiC paper I had at hand, over glass; the end result was the ceramic being somewhat more glazed & polished than it started out. As mentioned, if sandpaper is to work well at all, it's going to have to be much, much coarser than the desired target finish, something like sub-120 or so, for a finish like a medium Spyderco.

When mentioning how little swarf is generated, especially in trying medium or finer grits of SiC paper, I mean not even enough swarf to darken a clean microfiber towel after wiping down the stone with Windex or oil. If it can't even generate enough swarf to do that, it's a clue the abrasive isn't cutting very well as used in that form. Additionally, the paper backing of the sandpaper cushions the abrasive enough that it's even more diminished in it's ability to cut the alumina, which just compounds the tendency to overpolish, even when using relatively coarse grits. Same effect can even be seen in sharpening knives on sandpaper, leaving an effectively finer finish than if sharpening the same blade on a stone of the same rated grit.
 
Last edited:
Obsessed with Edges said:
I revisited this a little bit yesterday, experimenting with my Fallkniven DC4's ceramic side, which had a few glazed spots on it from use. Used a piece of fresh ~320-grit SiC paper I had at hand, over glass; the end result was the ceramic being somewhat more glazed & polished than it started out. As mentioned, if sandpaper is to work well at all, it's going to have to be much, much coarser than the desired target finish, something like sub-120 or so, for a finish like a medium Spyderco.

When mentioning how little swarf is generated, especially in trying medium or finer grits of SiC paper, I mean not even enough swarf to darken a clean microfiber towel after wiping down the stone with Windex or oil. If it can't even generate enough swarf to do that, it's a clue the abrasive isn't cutting very well as used in that form. Additionally, the paper backing of the sandpaper cushions the abrasive enough that it's even more diminished in it's ability to cut the alumina, which just compounds the tendency to overpolish, even when using relatively coarse grits. Same effect can even be seen in sharpening knives on sandpaper, leaving an effectively finer finish than if sharpening the same blade on a stone of the same rated grit.
Click to expand...
Hi,
You used
exactly How much force?
exactly What lubricant?
exactly How many passes / laps?
 
bucketstove said:
Hi,
You used
exactly How much force?
exactly What lubricant?
exactly How many passes / laps?
Click to expand...

A combination of things. First dry, with relatively light force (fingertip pressure), working in both / either of linear and figure 8 passes for 30 seconds - couple minutes, checking progress every 10-15 seconds by wiping the stone and looking for changes in the glaze. Then with some mineral oil on the paper, scrubbing in the same manner, just to see if clogging had been an issue with dry use (no difference). Little or no improvement in results, with the shiny areas gradually expanding in area and becoming even more glassy & polished-looking, rather than being reduced & replaced by a matte-like finish, as hoped. Even after use with the oil, still virtually no swarf coming off the stone or the paper itself (reinforces the tactile impression of smooth glass against smooth glass, as I mentioned earlier).

When I'd done this previously in the same manner with the HF 180-grit diamond hone on the Fallkniven ceramic, it took just seconds' worth of work to produce obvious scuffing of the ceramic, leaving new swirls of scratches on the surface and erasing the 'shine' from it completely within a minute or two. A breeze of a job, by comparison.
 
You must log in or register to reply here.
Back
Top