Lapping Plates and stones

[Dale Coons]

I bought a DMT DIA-Flat lapping plate a while back (it's a fairly new product--4 x 10 inches with 120 micron diamonds bonded to a 3/8" thick surface) and it does a great job on the norton stones I've had for a while--way better than the norton "flattening" stone. A couple of the ones I have are starting to wear and I'm thinking about moving to something that is less mess--perhaps some of the ceramic stones.

Anybody had any experience using that plate with something like glass stones? Chris Shwartz mentioned he'd sharpened his shaptons about 200 times on one, but doesn't say what kind of stones exactly they are.

I'd hate to bugger up a really nice sharpening stone using something to flatten it I shouldn't. This one isn't cheap, but a lot less than some other lapping plates that have breath-taking prices. Any experience/direction out there?

[Jim Matthews]

This should work fine. The Shapton system uses a loose grit on a milled steel plate.
You might be able to "refresh" the DMT if it stops cutting with a similar application.

In any case, the abrading surface will wear down over time. I doubt I'll sharpen my Shaptons 200 times in my life...

[Jason Coen]

That's exactly what I use to flatten the Glasstones I still have in rotation (and oilstones, and the backs of several old paring chisels, and anything else that needs it). I've completely worn out the 1k GS in about 18 months. Not the fault of the plate, as it works exactly as I hoped it would, but rather an indictment of the 1k GS.

[Jason Coen]

You might be able to "refresh" the DMT if it stops cutting with a similar application.

I'll be shocked if anyone other than a professional sharpener wears out one of the new Dia-Flat lapping plates. They hold up unbelievably well.

[Stuart Tierney]

The Dia-flat will work fine on Glass Stones.

FWIW, the Dia-flat is the 3rd most expensive waterstone flattening device commercially available, behind the 2 Shapton diamond flatteners and slightly ahead/equal with the Shapton plate/powder system.

Honestly, I'd prefer the Shapton things if I was going to spend more than $100 on a flattening device. I'd have to be strongly coerced to choose the Dia-flat over any of them.


Stu.


(Who's yet to be convinced in any way, shape or form that the Dia-flat is an actual solution to a real, tangible problem rather than an overkill solution that missed the mark (point) completely. Sorry.)

[John Coloccia]

The Dia-flat will work fine on Glass Stones.

FWIW, the Dia-flat is the 3rd most expensive waterstone flattening device commercially available, behind the 2 Shapton diamond flatteners and slightly ahead/equal with the Shapton plate/powder system.

Honestly, I'd prefer the Shapton things if I was going to spend more than $100 on a flattening device. I'd have to be strongly coerced to choose the Dia-flat over any of them.


Stu.


(Who's yet to be convinced in any way, shape or form that the Dia-flat is an actual solution to a real, tangible problem rather than an overkill solution that missed the mark (point) completely. Sorry.)

What do you recommend, Stu? I use a Duo (coarse for flattening). For me, sharpening isn't an experience. It's a chore that gets in the way of my real work, and I have an arsenal of sharpening equipment that I use for different situations...whatever gets me there the fastest and with least amount of work. For someone like me, what would you recommend?

[Jason Coen]

(Who's yet to be convinced in any way, shape or form that the Dia-flat is an actual solution to a real, tangible problem rather than an overkill solution that missed the mark (point) completely. Sorry.)

To each his own. What else is out there of an equivalent size that won't wear out quickly (like the DGLP - ask me how I know), doesn't use loose granules, or requires replacement sheets every time you wear out the surface?

The Dia-Flat has been as simple and as reliable as a hammer so far. I don't want to have to think about all the ancillary stuff that goes along with those that apparently hit the mark. Take it out, use it, put it away - what else is there to get right?

[Dale Coons]

Thanks all. Stu, since I already own the dia-sharp I wasn't looking to get another solution unless I had to. Sounds like it will work fine with whatever I wind up getting. You seem to be rather an expert in this area, so along with seeing what you recommend to John, I'd like your opinion on a good set for me--I'm not a neander by any stretch, but I do like sharp chisels and planes. I really hate the mess and soaking with the full set of nortons I have (220 thru 8000--the 220 is for rehabbing my granddad's chisels that my uncle used for a screwdriver, lever, etc), but do like the way the waterstones sharpen. I'm willing to pay for quality, but I'm not looking to break the bank.

[Stuart Tierney]

What do you recommend, Stu? I use a Duo (coarse for flattening). For me, sharpening isn't an experience. It's a chore that gets in the way of my real work, and I have an arsenal of sharpening equipment that I use for different situations...whatever gets me there the fastest and with least amount of work. For someone like me, what would you recommend?

Is the Duo flat? Yes? Then use it up!

I've got a Duo, and it works quite nicely some of the time. It is not my first choice for flattening stones because of the stiction and it doesn't seem to really 'bite into' the stones like the other options I do have. I do have some stones that I believe the Duo (XC) will be completely ineffective with due to it's design and the stone being flattened, not the diamond size or application to the plate. Of course, I've not even bothered trying it because previous experience tells me that the Duo will be ineffective and I don't want to use up that plate for nothing.

And the experience off the Duo is what troubles me about the Dia-flat. I have NO doubt it's a useful device that works well most of the time, and as is wont to happen, those who own XYZ device and have good results will defend their choice. This is good, since again, I have NO DOUBT WHATSOEVER that the Dia-flat works as well as advertised.

What I'm not convinced about is the size of the thing. I've performed thousands of stone flattenings (I can supply written documentation for over 1000 of those flattenings), and all done with an Atoma #400 that is no longer or wider than the stone it's flattening. I've made video showing that the stone is indeed flat after flattening, and that the Atoma did the task without undue difficulty. Heck, rub the Atoma on there, stone is flat. My 5 year old can do it. I'm not saying that the Atoma is the be all-end all, merely that a larger size plate than stone is not essential to effective, efficient flattening.

What I'm not convinced about is the #120 diamonds on it. It is common for many waterstone users to demand a finer grit diamond plate for their finer grit stones, claiming that coarser grit diamond plates leave large scratches in the stone, which can affect sharpening. Shapton's own loose grit on cast iron flattener includes coarse and fine powder for this exact reason. There's also a valid argument that fine stones require minimal flattening, and a finer medium for flattening allows one to creep up on flat without sending good stone down the drain.

What I'm absolutely not convinced about is the continuous surface of the Dia-flat. Take a look at an Atoma, and the surface is interrupted in the form of small, diamond 'pimples'. The iWood has diamond shaped areas with an uncoated strip between them. The Shapton plates have a dimpled surface. Every flattening 'stone' has relief in the surface to allow slurry to escape. Loose grit on glass/steel is done without pressure so the stone and steel are separated by the loose grit. None of the DMT plates have anything but a smooth, flat area and as such, suffer from stiction as mud locks the stone to the plate. This can be alleviated by regular flushing, and I suspect that the Dia-flat may escape too frequent stiction locking because of the #120 diamonds sticking up rather high. In my opinion, using a coarse diamond to alleviate stiction is not a solution to the problem, even if it does work of a fashion. However once the diamond wear down (as they do), you lose the ability for the plate to resist stiction, whereas interrupted surfaces never lose their stiction resistance, even when severely worn.

Granted, the Atoma and iWood will suffer from stiction, but it's rarely as severe or dangerous as the stiction that afflicts the Duo I have. The Atoma and iWood can be removed from a stone with a little water and a little pulling. Often the Duo 'locks' hard to the stone, that needs a lot of water and effort to break loose. I've dropped a stone on my foot twice because of the Duo, I've never lost control of stone or plate with an Atoma or iWood.

This has nothing to do with the quality of the plate, it's materials or anything else, my critique is purely based on it's design and some experience I have based on flattening several dozen different stone types by several different methods. I have to wonder if whoever actually designed the plate has flattened any more than a few, relatively benign sharpening stones (Shapton Pro/Glass, Norton, King Deluxe) and decided that "Hey, this works on them, all stones are the same so we're good to go!"

If you currently have a Dia-flat and like it, great. If you're buying one regardless of what I've written there, great. Granted, I do sell competition to the Dia-flat in the form of Atoma and iWood plates. I am also actively getting a proper diamond flattening plate hashed out with a manufacturer so anyone out there would rightly believe that I might be biased somewhat. I try to not allow any personal bias affect suggestions to anyone, except when I am 100% sure that by not being quite firm in a suggestion, I'd be doing a disservice to whoever reads what I have written.

I would ask that anyone considering one consider the above carefully. Perhaps I am looking too deeply into apparent 'problems' that don't actually exist in reality. But at the same time, I find that the Dia-flat is aggressively marketed as addressing problems suggested in other plates that don't actually exist in reality either.

I feel I've been too strong here, and do not wish to say anything more about the Dia-flat that could be construed as 'sour grapes' or a blatant attack on a product I feel threatened by as a seller of goods in competition with it.

Again, I'd dearly love to have one, and may (will) actually get one to see whether my fears are indeed justified or simply being overly sensitive after flattening nearly every waterstone commercially available and knowing that no two stones flatten the same, nor as easily as each other.

And believe me, if it's "that good" I'll be screaming it from the rooftops! But it's also got to deal with a few stones that I fear, quite rightly, that will tear it to pieces.

I hope that helps and doesn't raise too many hackles,

Stu.

[Jim Matthews]

TThe Dia-Flat has been as simple and as reliable as a hammer so far.

That's a sharpening technique unfamiliar to me...

[David Weaver]

Of all of the comments, #120 grit on fine stones is what I don't like. It's not that it doesn't work, it's that it's not necessary, and the expense isn't necessary, just as it isn't necessary to get a very aggressively priced shapton plate.

Grit at #120 large is only needed on sub 1000 grit stones, and there should be few times a person who is sharpening for a reason other than entertainment would need a 1000 grit stone such that norton 3x glued to something wouldn't do the trick (i.e., restoring a tool). The only one I can think of at all is the need for a coarser stone on japanese tools, where grinding may be a no-no (sandpaper still works, though).

The duosharp and the atoma are probably the two best choices out there for the money if you can manage to resist the temptation to sharpen steel items on them. The duosharp may require a little more water to avoid stiction, but it can handle oilstones, is generally cheaper, and you have a second side that you can put steel on if you like. The atoma is a bit nicer to use, and if you use one a lot, I think is worth the price difference.

I can't think of a stone 1000 grit or above that one or both (atoma may be a bad idea on oilstones unless you use them with dish soapy water) won't work on, unless the stone is a sintered diamond stone.

[Stuart Tierney]

I can't think of a stone 1000 grit or above that one or both (atoma may be a bad idea on oilstones unless you use them with dish soapy water) won't work on, unless the stone is a sintered diamond stone.

iWood and Atoma work on sintered diamond stones too. Not that it's something you want to do often, since the diamond stones are thin and expensive and you're not sending a few cents worth of binder and abrasive down the drain, more like a dollar of diamonds and binder. Not tried the Duo on a sintered diamond stone yet though.

Besides, sintered diamond stones are not exactly common out there in the world.

(For those out there wondering, a sintered diamond stone is a thin layer of diamond rich ceramic material bonded to a thick, aluminium plate backing. Resin type binder versions made by Naniwa and King also exist. They're quite expensive, not even as fast as a decent waterstone, but stay very flat and work with anything you can conjure up. Usually used for polishing/sharpening tungsten carbide knives and precision polishing of production die molds. They are usually supplied with a dressing stone for removing clogging and dressing the surface. 'Flattening' is generally not required. )

Stu.

(Going back to my recently arrived Ouchi chisel pricelist. Very interesting...)

[David Keller NC]

I can't comment on diamond stones used for flattening waterstones. I have 2 duo-sharps, both "coarse/extra coarse", but because I managed to convert one of these to "extra fine/fine" by removing about 10 thousandths of an inch of thickness from a Hock infill replacement blade ("beyond hard" is a good description of Ron's US-made irons), I decided I didn't want to take the chance of scrubbing the diamonds off with a Norton 1000 grit waterstone.

The reason I post this is that, on this one thing only, I disagree with the Schwarz. He notes that SiC wet-dry paper will be very expensive as a flattening system in the long run, and I suppose this is true if one is using the paper to both flatten the stone and refresh the surface, because you'd have to switch to a new piece of paper quite often. In my case, however, I use the paper only to flatten the stone, which means that I've been using the same 8.5 X 11" piece of 220g SiC for months. There's no doubt that the paper is far duller than when it started out, but it is still very effective at flattening the 1000, 4000 and 8000 grit Norton stones, and it's been used for the purpose for perhaps 100 or so flattenings.

The drawback to not refreshing the 220g paper is that you really can't remove a surface glaze from a 1000g stone - the fineness of the dulled grit on the paper removes the surface, but replaces it with another glaze. There's a definite and noticeable difference to the way a 1000g stone feels after flattening with water and a 220g SiC paper on a granite surface place vs. the way the same stone feels if it's been abraded by the Norton "flattening" plate under running water.

But to me, this is a difference without a distinction, because the first blade I flatten the back of will restore the stone's cutting efficiency if I am diligent about flushing it with running water during the process. So the summary for me is that SiC paper is quite a bit cheaper than $125 diamond plates, at least if I guesstimate the life of such a plate based on my experience sharpening hardened steel on diamond plates, and the posts here about how long a DMT plate lasts when used for flattening waterstones.

[Tony Shea]

I for one will never return to the SiC paper on granite to flatten my stones. Not sure how you pulled it off but my paper would never come close to lasting that long before replacing. Must be due to the fact I wasn't using nortons, started that proccess with Naniwa SS's. Have sinced switched to Shapton's and a Sigma finishing stone which is much harder than the Nortons. I currently use a Duo XC for flattening these stones, and have been for over two years now. It is a touch slower now but not by much. This is the only thing the diamond plate is used on and should last another 4 or more years. My only complaint is the coarseness on my finer stones. When I flip the duo over to the coarse side it works terribly at flattening my fine hard stones. There is too much stiction and just doesn't accomplish the task effeciently enough. This is what is holding me back from getting an Atoma 400 to flatten my finer stones. I;m affraid I will be dissapointed with the speed at which it works, as well as the stiction. I would love to get my scratches on my 10000 Sigma to be much finer than they are off of the Duo XC. I have not noticed any negative characteristics on my blades from these scratches though, so maybe it's another one of those real world problems that don't exist. But switching to an even coarser Dia-Flat 120 is just crazy. I would never touch such a coarse stone to my 1000 and up expensive waterstones.

So Stu, how is the Atoma 400's speed compared to an XC Duo on your finer Sigma Power's (10000g)? And is the stiction difference between the two that significant?

[Jason Coen]

But switching to an even coarser Dia-Flat 120 is just crazy. I would never touch such a coarse stone to my 1000 and up expensive waterstones.

Why not? I did it with my Shapton 16k and do it now with my Cho 10k whenever it needs it (which isn't often). It would take an awfully convincing argument to convince me it's in any way a bad idea.

And has anyone else actually used the Dia-Flat plate? It's not the same stone as the XX-coarse, and owning both, the wear properties of the two plates are completely different.

That said, I don't have a dog in all of this. I want sharpening to be as fast and as painless as possible. If there's a better way to do something then I'm all for it. As things stand for me now, the Dia-Flat comes out as the clear winner in the flattening department.