Waterstone flattening

I would suggest a diamond stone. It will always be flat.

-- Gary - Never pass up the opportunity to make a mistake look like you planned it that way - Tyler, TX

I agree. In fact, I use a diamond stone to flatten my Norton waterstones….I just rub my coarsest DMT diamond stone back and forth on the surface of the Norton waterstone while running them both under the faucet. Doesn’t take long to make it perfectly flat again.

-- -- Matt Sanfilippo, Pittsburgh, Pa., www.intheworkshop.info

I don’t really like that flattening stone, for that reason. You still have to dress the flattening stone on a regular basis, and personally I think it’s way to course. It removes way more material than is needed. I use a piece of float-glass (a slab of granite works nice too) and 220 wet/dry sandpaper. I’ve done a lot of research on this topic and there are more ways to sharpen tools than I can even count. There are two DVDs out there that I think are the best. They take different approaches and I have gotten good results with both. I have settle on the David Charlesworth approach. The other is from Rob Cosman, and he uses another 1000 grit stone to flatten his stones. Both DVD address the topic of keeping your stones flat.

David Charlesworth Hand Tool Techniques Part 1: Plane Sharpening

Rob Cosman Hand Planing and Sharpening

I agree with Matt. Just finish making and sharpening a skew chisel from a cheap straight chisel bought from a big box store. Used 4000-6000 Norton waterstone to hone the skew bevel after grinding on a slow speed grinder. Used a coarse DMT diamond stone to flatten the waterstone before and after use. One big caution. Dont use the garbage disposal side of the kitchen sink. Fine grit is tough on the disposal bearings. Dont ask how I know.

—Greybeard

-- Greybeard in Texas

Yes, I use the DMT diamond stone to flatten my 1000/4000 grit stone. It is also good to true up the plane body and sole.

-- John

I have the Norton flattening stone new in the box – looks like it’ll stay there after reading this! I’ve been pretty happy keeping my waterstones flat with my 12×15” 3/8” thick plate glass and whatever-grit-is-necessary-for-the-purpose sandpaper combination (it’s a bit cumbersome to use in the sink though – even in a utility sink). Also, have a granite slab which it great for dead flat work – like lapping backs, etc…

I think the diamond stone would be an improvement to the glass and sandpaper method to flatten stones though.

Isn’t it surprising how often you need to true up the face of waterstones! I’ve done a lot of reading over the past few years, but this was one point that I had to learn on my own.

-- Dorje (pronounced "door-jay"), Seattle, WA

Thanks for the input, everyone. Woodcraft is having a sale this weekend. I guess I’ll end up getting a DMT diamond stone. I don’t mind having to flatten the waterstone. I think of it as cleaning them up. I’d want to do that anyway. I do mind having to flatten the flattening stone. At some point, the madness has to end. :)

-- Disappointment is an empty box full of expectation.

According to the DMT salesman at last springs woodworking show the flattening stone is good for 6000/8000 grit stones where the stones will stick to the diamond stones. Anyone have any experience with this?

I had picked up a flattening stone just prior to buying a WorkSharp sharpener. Since buying the machine, I have not used my water stones. If I get some time, I will play around with them some.

-- We must guard our enthusiasm as we would our life - James Krenov

I just use a sheet of 100 grit paper taped to a piece of 1/2 inch glass. I strike some pencil lines across the stone and sand until all the pencil lines are gone. Then the stone is flat and I sharpen, depending on how much sharpening I have to do I repeat the process a few times.

-- Kaleo , http://www.kalafinefurniture.com

Wayne, I’m having a hard time parsing what you said. What’s this about sticking to the diamond stones?

-- Disappointment is an empty box full of expectation.

As long as you are running the stones under a faucet while you are flattening them with the DMT, I’ve had no problem with the grit sticking…

-- -- Matt Sanfilippo, Pittsburgh, Pa., www.intheworkshop.info

Surface tension can make the high grit stones stick to the diamond stone. I belive this is the thinking driving the groves in the top of the flattening stone.

-- We must guard our enthusiasm as we would our life - James Krenov

Well, I went to Woodcraft and picked up a DMT plus fine/extra fine stone. I went in there thinking I would get a coarse grit, but they were out of those and I wasn’t walking away empty handed. I’m actually perfectly OK with these grits, though, now that I have used them. I use the fine side to flatten my waterstones and it works great. I think I can say that my waterstones have never been this flat. By that, I mean that they are just flat; they are also smooth.

There is the issue of surface tension making the stones stick together. However, the motion is actually parallel to the surfaces and so the surface tension doesn’t really interfere with the shearing action of the flattening process. Also, the surface tension increases as the stones get flatter, so it actually provides feedback on how you’re doing. I don’t see it as a problem, at all.

I actually used both the fine and the extra fine grits to lap two of my plane blades that had gotten out of whack. I think they did a good job. Also, they are physically larger than my waterstones, which helped. Another nice thing is that I didn’t have to soak it, which I would have had to do with my coarse waterstone. I have one more blade to fix and I think I will lap that on the waterstone, just by way of comparison. The extra coarseness might make it go faster.

The other nice thing about the DMT stone is that I can use it for my card scrapers, which will be better than using my waterstones.

I’m pleased. Now, I just hope they stay as flat and as sharp for as long as they claim.

-- Disappointment is an empty box full of expectation.

This was a good discussion.

-- You can discover more about a person in an hour of play than in a year of conversation. (Plato)

Agreed!

-- Dorje (pronounced "door-jay"), Seattle, WA