USPS has delivered... How do I flatten ceramic stones??

[Peter Cobb]

I received both my expected packages on monday. The loot is:
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Holdfasts, Anarchists Toolchest, Essential Woodworker, and Honing compound from TFWW-
Spyderco stones, Tod Herrli DVD and The New Traditional Woodworker from Highland.

After unpacking the stones I decided to practice sharpening on the new stones. I flattened a chisel on sandpaper on a granite base (flat as far as I know).

I got the following result on the stones:
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This was refining the back of the chisel flat on the stones. :confused::eek::confused::eek::confused:

The ultrafine stone fan design actually ripples...
Any suggestions on flattening them?

Cheers,
Peter

[Peter Scoma]

Assuming they are ceramic, they shouldnt need to be flattened any time soon. Woodcraft describes the stone as having a "grain structure" that expedites sharpening. I suppose they are supposed to be that way? Maybe someone else who owns these stones can chime in.

PJS

[george wilson]

I haven't seen THAT. I thought the ultra fine was the regular white,but FLATTENED. I flattened my regular white stone with my diamond bench stone at the sink,using water a lot. I think I'd send that one back if you don't have a diamond bench stone. If you use diamond,hone lightly so as to not dislodge the diamonds.

If that is supposed to be a grain structure,it is too coarse for my liking. Maybe it's B.S. advertising to cover sloppy grinding?

[Salem Ganzhorn]

My spyderco has the same pattern but I don't think it is quite as pronounced. It doesn't seem to affect sharpening. But then again mine doesn't seem as severe. Have you tried the other side?
Salem

[george wilson]

Seems like it would affect sharpening narrow chisels. But,I can't tell how high the ridges actually are from the picture. I wouldn't want them.

[Trevor Walsh]

At work we flatten ceramic waterstones with a diamond lapping plate.

[Shaun Mahood]

Hi Peter, good timing on the spyderco stones - I just got mine in the mail 2 days ago. After your post I realized that I've been seeing the same thing in my brief use with the super-fine stone. I followed George's recommendations and got a 220 grit DMT Diasharp stone as well, so I decided to follow his original advice and flatten it. George, I think the ultra fine is probably a bit flatter than the fine, since it only took me about 20 minutes to flatten it (tried under the sink, but it worked much easier on the bench just spraying repeatedly with soap and water mixture).

Here is the side I left unflattened. The other side was similar to this though it had a different stripe pattern.
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Here is the flattened side. On both sides I ran the back of a 1.5 inch cheap chisel, moved it around a lot to try and get as full coverage as I could.
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The picture quality isn't that good, but I think the difference is quite obvious.

George, do you think I should do the same to my medium spyderco stone?

[Peter Cobb]

I haven't seen THAT. I thought the ultra fine was the regular white,but FLATTENED.

You seem to be right about that, the ultrafine is 11.2 mm thick vs 12.8 mm for the fine (0.441 vs 0.503 inches). But neither is flat. (I referenced them against each with a strong backlight, the shape of the light let through/contact points changed in all 4 configurations). I can slip a piece of paper (circa .1 mm/4 thou) from between them with no resistance. How flat is flat enough?? The medium grit is pretty much the same "flatness".

The "ripples" I commented on are not touchable but it chatters as I polish.


I think I'd send that one back if you don't have a diamond bench stone. If you use diamond,hone lightly so as to not dislodge the diamonds.

No diamond bench stone... and shipping them back would cost me around 40 bucks. I'm going to try to find a way to make do and mend.



My spyderco has the same pattern but I don't think it is quite as pronounced. It doesn't seem to affect sharpening. But then again mine doesn't seem as severe. Have you tried the other side?
Salem

The other side was the same beautiful, regular fan design... I actually can get it to show up without the chisel debris with light at the correct angle. I tried washing it off as I thought it might be a lapping residue, but no luck.

Suggestions cheerfully accepted,
Peter

PD I lay no blame at HighlandWoodworking, these stones were in the original Spyderco display/packages.
PPD I'll try spyderco's customer service tomorrow

[Peter Cobb]

Yep Shaun, I goofed on the DMT diasharp... should have got it too. I meant to use sand paper for the rougher grits. (Got the honing compound tho' it won't fix this. :D)
Just wondering won't the 220 (60 micron according to DMT (http://www.dmtsharp.com/products/colorcode.htm)) leave deeper scratches than the ones that are already there?
I'm starting to get confused...

[john brenton]

No comment on the stones, but you're going to love those Gramercy holdfasts. I'm using the heck out of them, and for most applications I just use hand pressure to lock them in place. Awesome.

[David Keller NC]

Peter - Other folks that chime in may be able to state this more definitively, but my strong impression is that ceramic stones are far too hard to flatten with anything other than a diamond substrate (you will wind up flattening the aluminum or silicon abrasive in sandpaper with the stone, rather than the other way around). That means either get a diamond stone, or get loose diamond paste and use a substrate. Theoretically, you could use the loose diamond paste on a granite surface plate, but the problem with that is that you will likely take the granite surface plate out of flat.

Another choice is a cast iron flattening plate intended to be used with diamond paste. Lee Valley sells one: http://www.leevalley.com/US/wood/page.aspx?p=59752&cat=1,43072

[george wilson]

My medium Spyderco has not needed any flattening,but I've had my stones for decades,and they could be differently made(or finished) by now. I wouldn't like those sloppy looking grinding "waves" on my stones,for sure.

Peter Cobb,Shipping would kill you for sure! I can't think of a way to flatten your stones without a diamond bench stone. The ceramic is far harder than anything else. Maybe rub your 2 ceramic stones together? Doesn't sound too effective,but they cut diamonds with diamonds. Maybe for those grinding marks it would work. Use water,or slightly soapy water,for sure.

I use soapy water as a honing fluid. Only a FEW drops of Dawn in a 1/2 pint squirt bottle of water. In the late 19th.C.,early 20th.C.,in England,they used soapy water to bore through armor plate with carbon steel drills when making early iron clads. Might have continued to do so for years longer. Certainly a cheap cutting fluid.

[Pam Niedermayer]

...Another choice is a cast iron flattening plate intended to be used with diamond paste. Lee Valley sells one: http://www.leevalley.com/US/wood/page.aspx?p=59752&cat=1,43072

Have you tried diamond paste on that LV plate? The description only mentions silicon carbide abrasives.

Pam

[george wilson]

If he wants to spend the money,I'd suggest a diamond bench stone. Those cast iron laps do not stay flat for long at all. Without a means to re surface them,you are out of luck. I wouldn't even want to resurface a cast iron lap in mt machines because I don't want to get diamond dust anywhere near them.

[Mason Chumpia]

Here is the side I left unflattened. The other side was similar to this though it had a different stripe pattern.
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Looks sort of like a Blanchard grinding pattern to me. Can you feel the pattern with your fingers?

[David Keller NC]

Have you tried diamond paste on that LV plate? The description only mentions silicon carbide abrasives.

Pam

No - The one time I tried diamond (loose) abrasives was on a spare chunk of granite surface plate - I immediately abandoned the technique as a false economy (because of dishing/"unflattening" granite surface plates!) and purchased diamond stones from DMT. I've heard of folks using cast-iron plates with diamonds, though - it apparently works (though I've no idea how well).

[george wilson]

Cast iron lapping plates were the standard for the machine shop for hundreds of years. I have a few nice ones that have never been used. BUT,the skillful lapper uses the plates very carefully,to try to keep the wear even as possible. Inevitably,they have to go back to the surface grinder to be refaced,something the home woodworker doesn't have available.

It may be better to use plate glass if you must use diamonds. You can get more plate glass locally and just toss the old worn out piece. You can probably get leftover pieces of glass for free,too.

[Peter Cobb]

Thanks George!
I spent a careful hour undishing the medium grit.
Will post pictures later
Cheers

[Peter Cobb]

If he wants to spend the money,I'd suggest a diamond bench stone. Those cast iron laps do not stay flat for long at all. Without a means to re surface them,you are out of luck. I wouldn't even want to resurface a cast iron lap in mt machines because I don't want to get diamond dust anywhere near them.

Well,
I went to the Borg bought a 4-in-1 diamond bench stone (cheap chinese is what they stock). There's always a second chance if I make a mess of it. So I set up shop:

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Set up a tartan hatch and started working. Changed the hatching to a silver colour the other one didn't photograph too well.

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After about half an hour, still got a couple of completely untouched spots: I marked 'em ot for the pic (bottom left corner and V at the top)

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My cheerful assistant helped all the way

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The grime on that stool is the ceramic I washed off!

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Seems to work fine.

[Shaun Mahood]

Thanks Peter, for some reason it never crossed my mind to put a grid on the stone. I was wondering how to tell if it was flat.

Guess I know what I'm doing for part of the weekend!

[Peter Cobb]

Here's the same process for the other ones. I'm amazed at how unflat they were :eek:.

Shaun, after erasing hatching for a while (about an hour and a half) I started writing on the stones :p, same idea though.

Did the ultrafine later (had to feed my assistant and change his nappies).

Now to see how they work.

Just for the record, I spent about an hour lapping each stone. Afternoon well spent I hope.

Cheers,

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[Shaun Mahood]

Peter, what did you use to write on the stones? I'm thinking of using permament markers but am not sure if it will soak into the stones.

[Jim Matthews]

I'm with George on the plate glass - cheap and VERY little deviation if it's "float" glass.

I use the Shapton polishing plate, for this purpose. I start with their daitomaceous (http://www.amazon.com/Thomas-Labratories-Diatomaceous-Earth-Shaker/dp/B00127Q860) earth grit, and use each subsequent slurry to polish the next finer stone.

It should be quick, or the stone isn't really made well.

[Peter Cobb]

Shaun, I simply used my daughter's colouring pencils (it's her winter holidays here, so she hauled all her stuff back from school).
You can see them in the 4th picture (red/blue beside my son, silver propped on the blue box lid top-right corner).
Cheers,
Peter

[Shaun Mahood]

This is one of the posts that reminds me how crazy the internet really is - we're on summer holidays here!
Thanks for this thread too, since without it I probably wouldn't have even checked my stones for flatness.